Astronomy

Can we see evidence of sunspots on other stars

Can we see evidence of sunspots on other stars


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Searching for exoplanets by measuring the change of a stars brightness when an exoplanet transits the star's disk also has the potential to detect exo-sunspots. Have they ever been detected?


Can we see evidence of sunspots on other stars?

Strictly speaking, no. Since there is one and only one Sun in the entire universe, there is one and only one star in the universe that has sunspots. That's rather pedantic. Going beyond that, the answer is almost certainly an emphatic yes. The generic term is starspots rather than sunspots, and they have been observed on other stars. For a very nice review, see the open source, peer reviewed article on starspots by K.G. Strassmeier.

The key issue with observing starspots on other stars is that even the largest sunspot observed on our Sun would be far too small / far too dim to resolve with even the largest of telescopes. But some stars apparently do have starspots much larger and much cooler than the largest / coolest sunspot on our Sun. Other than being larger and cooler, these very large starspots on other stars exhibit behaviors analogous to the sunspots observed on our Sun.

Starspots the size of the sunspots observed on our Sun almost certainly exist, but they currently can't be detected given the limitations of current technology.


Starspots can be detected indirectly, as seen here. From a talk I heard about this some years ago, the basic idea, or at least one of them, is to observe a sharp spectral line very precisely over time, measuring the exact "shape" of the line -- how much of the light was shifted to slightly higher or lower frequencies -- as it varied over time. A starspot slightly reduces the amount of light at higher frequencies when its on the part of the star rotating towards us, and slightly reduces the amount at lower frequencies when it's on the part rotating away. This signal is very faint, but has a precisely predictable structure and is periodic, so on rapidly rotating stars it can be detected among the noise with a lot of care.


The evidence for cool spots on stars, analogous to sunspots is extensive and overwhelming. Everything from the modulation of the measured light from stars as the spots rotate, to spectroscopic indicators of cool regions on the surface, to Doppler imaging that provides maps of the spot distribution on the surfaces of fast-rotating stars.

However, to answer your specific question, evidence for spots is seen as small "wobbles" in the transit signal from an exoplanet as it covers and uncovers individual spots or spot groups. An example of the literature on the topic is Mancini et al. (2016). The light curve data from Kepler and now TESS has made this a growing field of research.


Plasma flow near sun's surface explains sunspots, other solar phenomena

For 400 years people have tracked sunspots, the dark patches that appear for weeks at a time on the sun's surface. They have observed but been unable to explain why the number of spots peaks every 11 years.

A University of Washington study published this month in the journal Physics of Plasmas proposes a model of plasma motion that would explain the 11-year sunspot cycle and several other previously mysterious properties of the sun.

"Our model is completely different from a normal picture of the sun," said first author Thomas Jarboe, a UW professor of aeronautics and astronautics. "I really think we're the first people that are telling you the nature and source of solar magnetic phenomena -- how the sun works."

The authors created a model based on their previous work with fusion energy research. The model shows that a thin layer beneath the sun's surface is key to many of the features we see from Earth, like sunspots, magnetic reversals and solar flow, and is backed up by comparisons with observations of the sun.

"The observational data are key to confirming our picture of how the sun functions," Jarboe said.

In the new model, a thin layer of magnetic flux and plasma, or free-floating electrons, moves at different speeds on different parts of the sun. The difference in speed between the flows creates twists of magnetism, known as magnetic helicity, that are similar to what happens in some fusion reactor concepts.

"Every 11 years, the sun grows this layer until it's too big to be stable, and then it sloughs off," Jarboe said. Its departure exposes the lower layer of plasma moving in the opposite direction with a flipped magnetic field.

When the circuits in both hemispheres are moving at the same speed, more sunspots appear. When the circuits are different speeds, there is less sunspot activity. That mismatch, Jarboe says, may have happened during the decades of little sunspot activity known as the "Maunder Minimum."

"If the two hemispheres rotate at different speeds, then the sunspots near the equator won't match up, and the whole thing will die," Jarboe said.

"Scientists had thought that a sunspot was generated down at 30 percent of the depth of the sun, and then came up in a twisted rope of plasma that pops out," Jarboe said. Instead, his model shows that the sunspots are in the "supergranules" that form within the thin, subsurface layer of plasma that the study calculates to be roughly 100 to 300 miles (150 to 450 kilometers) thick, or a fraction of the sun's 430,000-mile radius.

"The sunspot is an amazing thing. There's nothing there, and then all of a sudden, you see it in a flash," Jarboe said.

The group's previous research has focused on fusion power reactors, which use very high temperatures similar to those inside the sun to separate hydrogen nuclei from their electrons. In both the sun and in fusion reactors the nuclei of two hydrogen atoms fuse together, releasing huge amounts of energy.

The type of reactor Jarboe has focused on, a spheromak, contains the electron plasma within a sphere that causes it to self-organize into certain patterns. When Jarboe began to consider the sun, he saw similarities, and created a model for what might be happening in the celestial body.

"For 100 years people have been researching this," Jarboe said. "Many of the features we're seeing are below the resolution of the models, so we can only find them in calculations."

Other properties explained by the theory, he said, include flow inside the sun, the twisting action that leads to sunspots and the total magnetic structure of the sun. The paper is likely to provoke intense discussion, Jarboe said.

"My hope is that scientists will look at their data in a new light, and the researchers who worked their whole lives to gather that data will have a new tool to understand what it all means," he said.


15.4 Space Weather

In the previous sections, we have seen that some of the particles coming off the Sun —either steadily as in the solar wind or in great bursts like CMEs—will reach Earth and its magnetosphere (the zone of magnetic influence that surrounds our planet). As if scientists did not have enough trouble trying to predict weather on Earth, this means that they are now facing the challenge of predicting the effects of solar storms on Earth. This field of research is called space weather when that weather turns stormy, our technology turns out to be at risk.

With thousands of satellites in orbit, astronauts taking up long-term residence in the International Space Station, millions of people using cell phones, GPS, and wireless communication, and nearly everyone relying on the availability of dependable electrical power, governments are now making major investments in trying to learn how to predict when solar storms will occur and how strongly they will affect Earth.

Some History

What we now study as space weather was first recognized (though not yet understood) in 1859, in what is now known as the Carrington Event . In early September of that year, two amateur astronomers, including Richard Carrington in England, independently observed a solar flare. This was followed a day or two later by a significant solar storm reaching the region of Earth’s magnetic field, which was soon overloaded with charged particles (see Earth as a Planet).

As a result, aurora activity was intense and the northern lights were visible well beyond their normal locations near the poles—as far south as Hawaii and the Caribbean. The glowing lights in the sky were so intense that some people reported getting up in the middle of the night, thinking it must be daylight.

The 1859 solar storm happened at a time when a new technology was beginning to tie people in the United States and some other countries together: the telegraph system. This was a machine and network for sending messages in code through overhead electrical wires (a bit like a very early version of the internet). The charged particles that overwhelmed Earth’s magnetic field descended toward our planet’s surface and affected the wires of the telegraph system. Sparks were seen coming out of exposed wires and out of the telegraph machines in the system’s offices.

The observation of the bright flare that preceded these effects on Earth led to scientific speculation that a connection existed between solar activity and impacts on Earth—this was the beginning of our understanding of what today we call space weather.

Link to Learning

Watch NASA scientists answer some questions about space weather, and discuss some effects it can have in space and on Earth.

Sources of Space Weather

Three solar phenomena— coronal hole s, solar flares, and CMEs—account for most of the space weather we experience. Coronal holes allow the solar wind to flow freely away from the Sun, unhindered by solar magnetic fields. When the solar wind reaches Earth, as we saw, it causes Earth’s magnetosphere to contract and then expand after the solar wind passes by. These changes can cause (usually mild) electromagnetic disturbances on Earth.

More serious are solar flare s, which shower the upper atmosphere of Earth with X-rays, energetic particles, and intense ultraviolet radiation. The X-rays and ultraviolet radiation can ionize atoms in Earth’s upper atmosphere, and the freed electrons can build up a charge on the surface of a spacecraft. When this static charge discharges, it can damage the electronics in the spacecraft—just as you can receive a shock when you walk across a carpet in your stocking feet in a dry climate and then touch a light switch or some other metal object.

Most disruptive are coronal mass ejection s. A CME is an erupting bubble of tens of millions of tons of gas blown away from the Sun into space. When this bubble reaches Earth a few days after leaving the Sun, it heats the ionosphere, which expands and reaches farther into space. As a consequence, friction between the atmosphere and spacecraft increases, dragging satellites to lower altitudes.

At the time of a particularly strong flare and CME in March 1989, the system responsible for tracking some 19,000 objects orbiting Earth temporarily lost track of 11,000 of them because their orbits were changed by the expansion of Earth’s atmosphere. During solar maximum , a number of satellites are brought to such a low altitude that they are destroyed by friction with the atmosphere. Both the Hubble Space Telescope and the International Space Station (Figure 15.24) require reboosts to higher altitude so that they can remain in orbit.

Solar Storm Damage on Earth

When a CME reaches Earth, it distorts Earth’s magnetic field. Since a changing magnetic field induces electrical current, the CME accelerates electrons, sometimes to very high speeds. These “killer electrons” can penetrate deep into satellites, sometimes destroying their electronics and permanently disabling operation. This has happened with some communications satellites.

Disturbances in Earth’s magnetic field can cause disruptions in communications, especially cell phone and wireless systems. In fact, disruptions can be expected to occur several times a year during solar maximum . Changes in Earth’s magnetic field due to CMEs can also cause surges in power lines large enough to burn out transformers and cause major power outages. For example, in 1989, parts of Montreal and Quebec Province in Canada were without power for up to 9 hours as a result of a major solar storm. Electrical outages due to CMEs are more likely to occur in North America than in Europe because North America is closer to Earth’s magnetic pole, where the currents induced by CMEs are strongest.

Besides changing the orbits of satellites, CMEs can also distort the signals sent by them. These effects can be large enough to reduce the accuracy of GPS-derived positions so that they cannot meet the limits required for airplane systems, which must know their positions to within 160 feet. Such disruptions caused by CMEs have occasionally forced the Federal Aviation Administration to restrict flights for minutes or, in a few cases, even days.

Solar storms also expose astronauts, passengers in high-flying airplanes, and even people on the surface of Earth to increased amounts of radiation. Astronauts, for example, are limited in the total amount of radiation to which they can be exposed during their careers. A single ill-timed solar outburst could end an astronaut’s career. This problem becomes increasingly serious as astronauts spend more time in space. For example, the typical daily dose of radiation aboard the Russian Mir space station was equivalent to about eight chest X-rays. One of the major challenges in planning the human exploration of Mars is devising a way to protect astronauts from high-energy solar radiation.

Advance warning of solar storms would help us minimize their disruptive effects. Power networks could be run at less than their full capacity so that they could absorb the effects of power surges. Communications networks could be prepared for malfunctions and have backup plans in place. Spacewalks could be timed to avoid major solar outbursts. Scientists are now trying to find ways to predict where and when flares and CMEs will occur, and whether they will be big, fast events or small, slow ones with little consequence for Earth.

The strategy is to relate changes in the appearance of small, active regions and changes in local magnetic fields on the Sun to subsequent eruptions. However, right now, our predictive capability is still poor, and so the only real warning we have is from actually seeing CMEs and flares occur. Since a CME travels outward at about 500 kilometers per second, an observation of an eruption provides several days warning at the distance of Earth. However, the severity of the impact on Earth depends on how the magnetic field associated with the CME is oriented relative to Earth’s magnetic field. The orientation can be measured only when the CME flows past a satellite we have put up for this purpose. However, it is located only about an hour upstream from Earth.

Space weather predictions are now available online to scientists and the public. Outlooks are given a week ahead, bulletins are issued when there is an event that is likely to be of interest to the public, and warnings and alerts are posted when an event is imminent or already under way (Figure 15.25).

Link to Learning

To find public information and alerts about space weather, you can turn to the National Space Weather Prediction Center or SpaceWeather for consolidated information from many sources.

Fortunately, we can expect calmer space weather for the next few years, since the most recent solar maximum , which was relatively weak, occurred in 2014, and scientists believe the current solar cycle to be one of the least active in recent history. We expect more satellites to be launched that will allow us to determine whether CMEs are headed toward Earth and how big they are. Models are being developed that will then allow scientists to use early information about the CME to predict its likely impact on Earth.

The hope is that by the time of the next maximum, solar weather forecasting will have some of the predictive capability that meteorologists have achieved for terrestrial weather at Earth’s surface. However, the most difficult events to predict are the largest and most damaging storms—hurricanes on Earth and extreme, rare storm events on the Sun. Thus, it is inevitable that the Sun will continue to surprise us.

Example 15.1

The Timing of Solar Events

Dividing both sides by v, we get

Suppose you observe a major solar flare while astronauts are orbiting Earth. If the average speed of solar wind is 400 km/s and the distance to the Sun as 1.496 × 10 8 km, how long it will before the charged particles ejected from the Sun during the flare reach the space station?

Solution

Check Your Learning

Answer:

1.496 × 10 8 km 500 km/s = 2.99 × 10 5 s , or 2.99 × 10 5 s 60 s/min × 60 min/h × 24 h/d = 3.46 d 1.496 × 10 8 km 500 km/s = 2.99 × 10 5 s , or 2.99 × 10 5 s 60 s/min × 60 min/h × 24 h/d = 3.46 d

Earth’s Climate and the Sunspot Cycle: Is There a Connection?

While the Sun rises faithfully every day at a time that can be calculated precisely, scientists have determined that the Sun’s energy output is not truly constant but varies over the centuries by a small amount—probably less than 1%. We’ve seen that the number of sunspots varies, with the time between sunspot maxima of about 11 years, and that the number of sunspots at maximum is not always the same. Considerable evidence shows that between the years 1645 and 1715, the number of sunspots, even at sunspot maximum, was much lower than it is now. This interval of significantly low sunspot numbers was first noted by Gustav Spӧrer in 1887 and then by E. W. Maunder in 1890 it is now called the Maunder Minimum . The variation in the number of sunspots over the past three centuries is shown in Figure 15.26. Besides the Maunder Minimum in the seventeenth century, sunspot numbers were somewhat lower during the first part of the nineteenth century than they are now this period is called the Little Maunder Minimum.

When the number of sunspots is high, the Sun is active in various other ways as well, and, as we will see in several sections below, some of this activity affects Earth directly. For example, there are more aurora l displays when the sunspot number is high. Auroras are caused when energetically charged particles from the Sun interact with Earth’s magnetosphere , and the Sun is more likely to spew out particles when it is active and the sunspot number is high. Historical accounts also indicate that auroral activity was abnormally low throughout the several decades of the Maunder Minimum.

The Maunder Minimum was a time of exceptionally low temperatures in Europe—so low that this period is described as the Little Ice Age . This coincidence in time caused scientists to try to understand whether small changes in the Sun could affect the climate on Earth. There is clear evidence that it was unusually cold in Europe during part of the seventeenth century. The River Thames in London froze at least 11 times, ice appeared in the oceans off the coasts of southeast England, and low summer temperatures led to short growing seasons and poor harvests. However, whether and how changes on the Sun on this timescale influence Earth’s climate is still a matter of debate among scientists.

Other small changes in climate like the Little Ice Age have occurred and have had their impacts on human history. For example, explorers from Norway first colonized Iceland and then reached Greenland by 986. From there, they were able to make repeated visits to the northeastern coasts of North America, including Newfoundland, between about 1000 and 1350. (The ships of the time did not allow the Norse explorers to travel all the way to North America directly, but only from Greenland, which served as a station for further exploration.)

Most of Greenland is covered by ice, and the Greenland station was never self-sufficient rather, it depended on imports of food and other goods from Norway for its survival. When a little ice age began in the thirteenth century, voyaging became very difficult, and support of the Greenland colony was no longer possible. The last-known contact with it was made by a ship from Iceland blown off course in 1410. When European ships again began to visit Greenland in 1577, the entire colony there had disappeared.

The estimated dates for these patterns of migration follow what we know about solar activity. Solar activity was unusually high between 1100 and 1250, which includes the time when the first European contacts were made with North America. Activity was low from 1280 to 1340 and there was a little ice age, which was about the time regular contact with North America and between Greenland and Europe stopped.

One must be cautious, however, about assuming that low sunspot numbers or variations in the Sun’s output of energy caused the Little Ice Age. There is no satisfactory model that can explain how a reduction in solar activity might cause cooler temperatures on Earth. An alternative possibility is that the cold weather during the Little Ice Age was related to volcanic activity. Volcanoes can eject aerosols (tiny droplets or particles) into the atmosphere that efficiently reflect sunlight. Observations show, for example, that the Pinatubo eruption in 1991 ejected SO2 aerosols into the atmosphere, which reduced the amount of sunlight reaching Earth’s surface enough to lower global temperatures by 0.4 °C.

Satellite data show that the energy output from the Sun during a solar cycle varies by only about 0.1%. We know of no physical process that would explain how such a small variation could cause global temperature changes. The level of solar activity may, however, have other effects. For example, although the Sun’s total energy output varies by only 0.1% during a solar cycle, its extreme ultraviolet radiation is 10 times higher at times of solar maximum than at solar minimum. This large variation can affect the chemistry and temperature structure of the upper atmosphere. One effect might be a reduction in the ozone layer and a cooling of the stratosphere near Earth’s poles. This, in turn, could change the circulation patterns of winds aloft and, hence, the tracks of storms. There is some recent evidence that variations in regional rainfall correlate better with solar activity than does the global temperature of Earth. But, as you can see, the relationship between what happens on the Sun and what happens to Earth’s climate over the short term is still an area that scientists are investigating and debating.

Whatever the effects of solar activity may be on local rainfall or temperature patterns, we want to emphasize one important idea: Our climate change data and the models developed to account for the data consistently show that solar variability is not the cause of the global warming that has occurred during the past 50 years.


The Sunspot Cycle

Between 1826 and 1850, Heinrich Schwabe , a German pharmacist and amateur astronomer, kept daily records of the number of sunspots. What he was really looking for was a planet inside the orbit of Mercury, which he hoped to find by observing its dark silhouette as it passed between the Sun and Earth. He failed to find the hoped-for planet, but his diligence paid off with an even-more important discovery: the sunspot cycle. He found that the number of sunspots varied systematically, in cycles about a decade long.

What Schwabe observed was that, although individual spots are short lived, the total number visible on the Sun at any one time was likely to be very much greater at certain times—the periods of sunspot maximum—than at other times—the periods of sunspot minimum. We now know that sunspot maxima occur at an average interval of 11 years, but the intervals between successive maxima have ranged from as short as 9 years to as long as 14 years. During sunspot maxima , more than 100 spots can often be seen at once. Even then, less than one-half of one percent of the Sun’s surface is covered by spots. During sunspot minima , sometimes no spots are visible. The Sun’s activity reached its most recent maximum in 2014.

In 2000 an IMAX move about the solar cycle was released. Here is a link to the official trailer. While dated, it is still worth watching.


Comments

Worrying about changes over 100 years of the lifetime of the sun is equivalent to worrying about 1 minute in the course of a human lifetime. Is how you behave in one minute of your life a "sign of a deeper trend". Perspective, people.

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Person using the handle "CosmicLettuce", you seem to have mis-read the article. There is no suggestion here that the Sun is "dying" or that there is anything fundamentally changing in the Sun's basic energy output. The "deeper trend" referred to is clearly a longer trend in the sunspot cycles. The sunspot cycles and the resulting "space weather" have a significant impact on radio communications, GPS positioning, satellite orbital decay, power grids, and other technological matters, as well as likely, though unproven, impacts on climate and weather. If this present weak cycle is in fact a sign of a deeper trend, then it is absolutely newsworthy and relevant and you should adjust your perspective if you don't see that. A Sun with a quiescent sunspot cycle could save civilization globally hundreds of billions of dollars in various ways over a fifty year period. But it could also generate dangerous complacency which could bite us hard when the cycles become strong again. And no one has any idea how to predict this.

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But on the other hand (from CL&rsquos comment), since the sun&rsquos output is far and away the most important factor in how hot it is here on earth, determining the rate of change (if there is any) in the sun&rsquos output even during human scale time frames could be very important. Frank Reed, I agree almost completely with your comment, accept, hasn&rsquot the case been &ldquoproven&rdquo that the human caused CO2 atmospheric increase is starting to cause climate and weather change? I know that there are many doubters, but hasn&rsquot the science community come to a consensus on this? Also, 2 more questions. Is there any measurable change in the energy earth receives between the highs and lows of the 11 year sunspot cycle? And if there isn&rsquot, what accounts for the time correlation between the Maunder Minimum and the Little Ice Age?

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January 24, 2017 at 12:25 pm

Consensus is political term, and is not science. Proof is science. Proof has not been shown that trace gases actually cause much of a greenhouse effect at their present levels of hundreds of parts per million, or thousands of parts of billion, or trillion. CO2 has risen as a portion of the air only 0.012% since the industrial revolution began. #TraceGasWarming is #ChickenLittleScience.

Water, however, is the main greenhouse gas as well as being the coolant of the land, moderating our temperatures. It has a lot more chance to cool the land when being sprayed all over vegetation and the ground by sprinklers, creating more cooling evaporation which eventually condenses into cooling rain somewhere else and sometimes right where they are generated. But we have been told since the '80s that we must save fresh water regardless of local supplies and conditions, with evaporation being called "waste," and water rates raised far beyond the cost of production and delivery, such that many cities on the West Coast have gone dry, weedy, and become fire hazards.

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Science does not know such things as "consensus" or confirmation by the number of scientists supporting a theory. Remember the exclamation by Galileo Galilei: "Eppur si muove"!

A question: It is possible that increase of the atmospheric CO2 is a consequence of the global temperature recovering from the Little Ice Age?

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@BruceMayfield
"Is there any measurable change in the energy earth receives between the highs and lows of the 11 year sunspot cycle? And if there isn&rsquot, what accounts for the time correlation between the Maunder Minimum and the Little Ice Age?" - question is not so much about the total energy received but about its distribution over low and high energy particles. CERN research famously hushed up by the directors in 2011 ("you can publish the numbers but not interpret them") confirmed long existing theory (that originally emerged from known long term correlation of Earth's global temperature and Be isotope concentrations in related strata) that can be simplified to "if energy Earth receives comes in form of particles with higher individual energies - the process of warming is more efficient due to the interaction of those particles and water vapor in the atmosphere". So, Solar cycle related warming and cooling is not so much about total energy received but more high energy particles - as in Solar maximums.

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@BruceMayfield "hasn&rsquot the case been &ldquoproven&rdquo that the human caused CO2 atmospheric increase is starting to cause climate and weather change?" - unfortunately individual and Governmental ideology have had impact on "proven" issue. In my opinion there are two experimental facts that highly challenge (and disprove) that theory:
1) Find MIT/NASA satellite global temperature study from late 1990's. Evidence: global temperatures rose each year CO2 concentrations went up each year . proportion of the energy Earth returned to space to incoming energy ROSE EACH YEAR (measurable, way beyond error limits).
Definition of greenhouse effect: system receives some energy, absorbs some, returns some, amount o absorbed energy keeps system at temperature T1. We introduce some greenhouse factor that reflects back some of returned energy. More energy is absorbed, system is at higher T2>T1. LESS energy is reflected to the surroundings. MIT/NASA precise, long term study EXCLUDES any form of greenhouse effect as a cause of Earth warming during that period. Natural CO2, human produced CO2, something else we know of or do not know of. Simply whatever warmed the Earth couldn't have been a greenhouse effect of any kind. (See my first reply - greater efficiency of utilizing received energy could do this).

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Dusanmal, thank you for those answers. Your first comment explained how even with steady overall energy coming from the Sun we could still have differing heating of the Earth&rsquos atmosphere depending upon the levels of magnetic activity on the Sun. I find it a bit ironic that to some the obvious fact that the Sun is the main driver in global temps is also &ldquoan inconvenient truth.&rdquo In a perfect world scientists would be free to collect data and draw objective, unbiased conclusions based purely on fact and logic. But with vast sums of money involved on both sides of the global warming issue the public is left wondering, whose experts can we trust? Meanwhile global weather certainly seems to be getting more and more extreme, and almost all glaciers the world over are in serious retreat. (If any are in doubt on this second point, watching the film &ldquoChasing Ice&rdquo should be eye opening.) Dusanmal&rsquos second posting casts doubt upon manmade CO2 as being responsible for global warming, but is his reasoning sound?

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The solar activity has very little to do with its energy output and thus the amount of energy reaching Earth. The energy leaving the Sun as light and heat has its origin deep within its core, where fusion is happening at a very constant rate. The solar activity that we see in sunspots, faculae and prominences is generated much higher up by magnetic effects within the electrically guiding plasma. Which is very different again from the effect that drives pulsating variable stars.
Whether the Maunder minimum of sunspots was the actual reason for the cold winters in Europe at all is by no means established, and then, it was a regional effect. Please see this excellent article by the "Bad Astronomer" Phil Plait: http://blogs.discovermagazine.com/badastronomy/2011/06/17/are-we-headed-for-a-new-ice-age/

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Bruce, just so we're clear, I didn't say anything AT ALL about CO2 and climate. I said that there were "unproven impacts on climate and weather" related to the sunspot cycle --an entirely different question (and the topic of this article). In Phil Plait's blog article, mentioned in the previous comment, he paraphrase Doug Biesecker saying he "points out that a weak cycle may not have an effect on our climate we simply don&rsquot know for sure." BUT it has long been considered a reasonable scenario nonetheless. Though the Sun's overall energy output is very likely constant to a high degree of accuracy, and actual measurements from orbit show little measurable variation, slight variations in the spectral distribution of sunlight and also its latitudinal distribution (sunspots do not occur near the Sun's poles) could easily have some effect on the Earth's climate, especially if the sunspot cycle actually shuts down, which at this point is only a small possibility --we just don't have a lot of data on this. These discussions have their own "cycles". It has become less fashionable in recent years to discuss external forcing of Earth's climate since many people fear that it will distract attention from internal forcing and anthropogenic warming. That's a shame.

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At some point we could quit arguing about it, and just accept that whatever natural forces governed climate in the past, God has now put mankind in charge of maintaining conditions conducive to life in the future. Look at the famous &ldquohockey stick&rdquo graph. Before the recent upwards spike, global temperature was trending down. The Earth&rsquos orbit is changing back into ice-age conditions. The Little Ice Age was a taste of what was to come. We have burned enough buried carbon to stave off the next ice-age. Phew! We should not be arguing about whether or not we can impact climate the debate should be over what temp to set the thermostat at.

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Frank Reed, yes, I did realize that your first posting was about the solar magnetic threat and not global warming, but one could make somewhat similar arguments about the global warming issue too. And, let me clarify as well, I&rsquom not in the manmade global warming deniers club, even though I made a comment entitled &ldquoSun Driven Global Warming&rdquo. But one hears this argument so often, and since this fact is so significant (we do get almost all our warmth from the sun, after all) any story about changes in the Sun are bound to be seized upon by those who want to let man off the hook and blame it all on old Sol. But I&rsquom just a guy trying to sift out the facts from the hype and spin so that I can come to a well reasoned fact based opinion. So I thank Dieter Kreuer for providing the link to Phil Plait&rsquos writings which were very helpful, showing that the Maunder Minimum/Little Ice Age connection doesn&rsquot prove as much as it may at first seem. But we still have Dusanmal&rsquos &ldquoWhat is Greenhouse effect?&rdquo post, which no one has contested yet &hellip

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Dusanmal, thanks again for your answers. In my second post of this thread I responded to your first post, but I think your second comment isn&rsquot nearly as sound as your first. The fact that CO2 is a greenhouse gas is provable in a lab, isn&rsquot it? You admit that global temps and CO2 percentages are both on the rise, but then you seem to be making a point that the ratio of outgoing to incoming energy increasing is a problem. Since incoming energy (from the Sun) is reasonably constant, if the Earth&rsquos temp rises then the amount of heat radiated back into space will also rise, increasing this ratio. In fact the ratio of outgoing to incoming energy is and always has been over 1, because in addition to solar heating the earth is also continually shedding heat that has flowed up from its interior. And now we have humanity burning fossil fuels at an ever increasing pace, adding to the heat each year. Slash and burn and overly frequent plowing agricultural practices also add to the heating. Cities are known to be &ldquoheat islands&rdquo with warmer local temps, and the size of cities grow with increasing human population, which raises the overall average. Hey, wait a minute did I just explain anthropomorphic global warming without invoking the greenhouse effect. See how many factors are at work here! Yes Peter, the debate about whether we are impacting climate should be over. But what should be done about it is the 64 trillion dollar question.

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The post claiming "whatever warmed the Earth couldn't have been a greenhouse effect of any kind" is simply wrong. There are other variables such as ocean surface temperatures (influenced by El Nino and La Nina) that affect the amount of thermal radiation returned to space. When these are accounted for, researchers find no significant discrepancies in climate models that predict warming with increasing greenhouse gas concentrations. Indeed, the oceans are still increasing in heat content at a significant rate, with recent evidence indicating that some of the heat is going into the deep oceans. All of this despite relatively mild solar activity in recent years.

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Thanks Dr. Young for this clear and interesting report. To everyone else -- Aside from the practical effects of solar radiation on vulnerable technologies and the possible correlations between solar activity and terrestrial climate, the anomalies between this solar cycle and previous cycles, and the befuddlement of the scientists who study the Sun, are just plain interesting! The Sun is the only star we can image and study in such close detail, so it's our best sample of the population of all the other stars, although almost certainly a skewed sample. E.g., the Kepler space telescope discovered that on average "Sun-like stars" are slightly more variable than dear old Sol. The things we don't understand about our own Sun are, ipso facto, an important area of study for astronomy generally.

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I am fully prepared to receive a storm of criticism for this post, but nonetheless it needs to be stated. There is currently NO data to indicate that the multi-event Ice Age cycle of the past couple million years has come to an end. What if we are merely in yet another interglacial warm period, and that sooner or later the ice sheets will come back. In fact historical data, derived from core samples, suggests that the onset of an ice age is quick, a matter of decades, and often they are foreshadowed by unexplained warming cycles just prior to onset. Man is definitely warming the planet, no doubt about that at all, but glacier records from the Swiss Alps show that they were receding steadily throughout the 1700's, well prior to the advent of the Industrial Revolution. So we seem to be experiencing warming from two sources man and his heedless burning of fossil fuels, but also a larger cycle that just might prefigure a plunge into yet another ice age. I predict this will happen in the lifetimes of some who are alive today. By 2050 deep snowfalls will be a regular occurrence in cities like Los Angeles and Phoenix, both of which have no historical record of such a thing.

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@Bruce Mayfield: "hasn&rsquot the case been &ldquoproven&rdquo that the human caused CO2 atmospheric increase is starting to cause climate and weather change?"

Anybody with experience analyzing closed systems knows very well that you cannot fiddle with the parameter values of the system without having consequences. One does not simply remove 40% of the planet's CO2-sequestering canopy and replace it with pasture, CAFOs, manmade structures and fill the free space with cars, trucks and airplanes . and then expect no changes.

There is ALWAYS cause and effect. The question, therefore, is not whether we're having an effect, but whether the amount of input to the system is sustainable. Given the complexities of particulate causing global dimming, it's just not straight forward to recognize at what point we're at the point of no return. That said, after 9/11 when all the air traffic was grounded, particulate in the atmosphere decreased and we saw immediate ground-level temperature increases of 1-2 deg C within days.

@Dusanmal: "global temperatures rose each year CO2 concentrations went up each year . proportion of the energy Earth returned to space to incoming energy ROSE EACH YEAR (measurable, way beyond error limits)."

The problem is that "energy returned to space" can be the amount reflected from particulate and aerosols before it reaches the surface. What we're mostly concerned about is the amount of energy that is reaching the ground and how much of that overall energy that is staying in the system is being released. Unfortunately, the maths don't look good there.

Even if we take your statements at face value, however, it makes zero sense to stick with 30-year-old data as Truth. So, how about we fast forward to 2009 and see what MIT has to say this time?

Oops. Not nearly so good anymore.

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2004 article:
About the long-term coordinated variations
of the activity, radius, total irradiance of the
Sun and the Earth&rsquos climate
Habibullo I. Abdussamatov
Pulkovo Observatory, Saint Petersburg, Russia

Prediction, (dating from 1998): Weaker Solar Cycle 24, almost non-existant solar cycle 25, 26 and likely 27.

So far he is a lot closer than the IPCC's experts.

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I don&rsquot understand what the reason for hyping this is or why any major periodical supporting astronomy would put out so many negative stories dissuading people from possibly getting involved in solar astronomy.

Perhaps the data indicates that this is a weak solar cycle, I believe it is simply interpreted this way for the purpose of this article, but either way&hellipWHO CARES. How about SUPPORTING the hobby instead of always talking about how low the activity is? These articles are always spread by people who have never looked through an H-Alpha scope or by nighttime astronomers who think they have &ldquo&rdquouncovered&rdquo something important about a hobby they know almost nothing about.

I can tell you for absolute certainty that if you get out a solar scope and look through it-the first thing that comes to your mind will be how incredibly fascinating it is to look at the Sun, you&rsquore probably not going to say &ldquoWow, what a weak solar cycle&rdquo .

Can we get more positive news about our hobby instead of this constant ignorance or downright naysaying about the absolute fastest growing portion of modern astronomy-Solar?

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Jim Baughman, wow dude, what a CHILLING prediction. (Sorry, but it needed to be stated.) But as somewhat of a contrarian myself, your radical suggestion does have a certain degree of fringe appeal. But if people were to heed your warning then people should heedlessly continue the &ldquoheedless burning of fossil fuels&rdquo. Sorry Jim, but I think Peter is more likely correct when he quipped that &lsquowe have staved off the next ice-age&rsquo. But if I had to make a prediction (which I don&rsquot, so I&rsquom not) I&rsquod have to say that it is far more likely that we might see the opposite disaster, a total melt-down and shift completely away from glacial coverage resulting in massive sea-level rise. (I wonder, isn&rsquot little or no ice more common than ice ages in Earth&rsquos history?)

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The famous &ldquohockey stick&rdquo graph has been infamous for several years.

Pro-CO2 climate climate scientist from the Danish Meteorological Institute, Copenhagen, Denmark, tested the software and found that different "red noise" data sets produced hockey sticks.

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The sun has become old, and it is gradually losing its heat, but this is difficult for observers to decide, because of the tremendous heat of the sun.

Actually, yes, the sun is losing its heat, and this is a gradual process.

It is acquiring a membranous and incomplete crust, but the process is proceeding and is in progress.

This explains many things including the recent change in the solar cycle, its delaying and its weakness.

The complete cooling of the sun surface will take about 2000 years, after which the sun will burst and break up into 19 pieces (in the next Doomsday.)

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You can make google search about these titles:

The Recent Solar Cycle 24 is the Weakest in 100 Years

The Sun will tear up, after the ending of its life, and become nineteen pieces

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Eric Holcomb and Trane Francks, your points were excellent. Also, in the recent &ldquoA Fix for the Faint Young Sun Paradox&rdquo newsblog Tom Yelin and Peter made comments that shed light on this conversation as well.
Tom Yelin wrote: &ldquoKelly writes that the current carbon dioxide concentration is 360 ppm. This is incorrect. It is now 400 ppm (or very nearly that).&rdquo
Peter then wrote: &ldquoObservations suggest: delta_T = k*log(CO2), where k is a constant. In other words, if doubling CO2 concentration raises Earth's temperature 4 degrees, doubling it again will raise it another 4. A warm world is better than a frozen one. On the other hand, thresholds exist, so we are kind of playing with fire.&rdquo
Another reference that was most informative is climate.nasa.gov/evidence At the top of this web page under the question &ldquoClimate change: how do we know?&rdquo a graph is provided showing CO2 levels over the last 400,000 years. It shows the massive spike upward in recent years and confirms that CO2 was (at the time the chart was published) about 383 ppm. If the formula Peter provided is valid then we are already in trouble, because it would take less than a 4 degree global temperature rise to cause significant change in sea level. Before I was as informed on this I was going to say, what, do we have to wait until sea level rise is observed before we believe this can happen, but I see from NASA&rsquos web page that &ldquoGlobal sea level rose about 17cm in the last century. The rate in the last decade, however, is nearly double that of the last century.&rdquo Intelligent people can disagree about which factor is the greatest cause, but the fact that global warming is happening is beyond all reasonable doubt.

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We will probably see a total melt-down and shift away from glacial coverage resulting in massive sea-level rise, but this will only look like a disaster from out point of view. For sea-life, the 20th century was a disaster. From our using the ocean as a sewer, to farm fertilizer run-off, to shark-finning, but especially due to fossil-fuel powered, refrigerated, factory fishing-vessels ravaging the ocean with the latest fish-finding technology, mankind&rsquos euphoric discovery of fossil fuels has been a disaster for marine life. A recent article describes government plans to kill 100 sharks near an Indian ocean island, because 1 shark killed a 15-year old swimmer. Yeah, that'll teach 'em! If sea levels rise 20 meters and drown our coastal cities, as well as a few islands, there will be no sharks weeping over it.

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Mankind sure has messed things up, haven&rsquot we Peter. To the things your mentioned acidification of the seas, wide scale deforestation, reduction of biodiversity and other things I&rsquom sure can also be sited. I&rsquom reminded of what an ancient Hebrew prophet once wrote, &ldquoIt does not belong to man who is walking even to direct his step.&rdquo (Jeremiah 10:23) The solutions to these problems are far beyond what man in his much less than infinite wisdom can find. This also reminds me of a prophecy that there would come a time when God would &ldquobring to ruin those ruining the earth.&rdquo (Revelation 11:18) Even many who don&rsquot believe that there is a God should be able to see that the Earth is being ruined. I remain hopeful however, due to what Isaiah wrote at Isaiah 45:18, and what Jesus said at Mathew 5:5, &ldquoBlessed are the meek: for they shall inherit the earth.&rdquo

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November 1, 2013 at 4:30 pm

In the past year 1 million plus farm herd animals buried alive in snow in the UK, Ireland, NZ, Peru, Argentina and now Dakota. Five straight cold winters in the UK is just the start of a steady decline into cycle 25 sun minimum.

UV radiation which has deeper penetration of the seas has much more radical swings of energy than TSI. Add in Forbush events impacting Cosmic Ray Cloud formation and there is a clear mechanism in solar variation impacting climate on earth.

With tens of thousands of volcanic underseas vents and volcano the oceans release CO2 when they warm and retain CO2 more when cold. During the last ice age the CO2 in the atmosphere reach near plant life starvation levels. When the earth warms the CO2 follow by about 800 years.

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December 19, 2013 at 6:46 pm

This morning I didn't even know what a sunspot or solar cycle is, so doubtless my comment is valueless, but I can't resist.
If the north and south hemispheres are out of phase with each other-- asymmetric--wouldn't that automatically reduce the magnetic field of the sunspots? I mean, carrying the analogy of the sun to a bar magnet, if you distort the magnet. . . . So if the whole magnetic field is weaker, then the sunspots can't express it, or draw on it, or whatever. Sorry. Terribly facile.


Chinese Astronomy - The Legacy

The Chinese astronomers have often been looked over in favor of the Greek, Indian, and Islamic contributions to the field, mainly because they use such different methods from the Eurocentric world. Their work tended to be more concerned with refining their observations and making ever more accurate measurements than developing theories but, in that respect, they were one of the leading ancient cultures.

The Chinese astronomers generated fantastically accurate measurements of time and charted unusual cosmological phenomena, such as novae, comets and meteor showers. This makes their work important to the development of the history of astronomy, and their ideas filtered down the Silk Road into the Middle East and Europe.


Can we see evidence of sunspots on other stars - Astronomy

Why are sunspots created? What is the reason behind them?

Sunspots appear darker than the rest of the surface of the Sun because they are cooler. The center of a sunspot (called the umbra) has a temperature of around 3700 Kelvin while the surrounding photosphere has a temperature of 5800 Kelvin. Sunspots are also regions of strong magnetic fields (thousands times stronger than the Earth's field) and usually occur in pairs (one being a north pole and the other being a south pole).

Why certain regions on the Sun's surface are cooler than others is not well understood. One theory is that the strong magnetic fields in these spots inhibit convection below the surface. (Convection is the transfer of heat from a hot location to a cold one.)

This page was last updated June 28, 2015.

About the Author

Sabrina Stierwalt

Sabrina was a graduate student at Cornell until 2009 when she moved to Los Angeles to become a researcher at Caltech. She now studies galaxy mergers at the University of Virginia and the National Radio Astronomy Observatory in Charlottesville. You can also find her answering science questions in her weekly podcast as Everyday Einstein.


The Milky Way ate another galaxy, and we can still see the undigested bits

We know this for many reasons. For one, we can see other galaxies colliding and merging all over the sky. For another, we can track stars on our galaxy that were once part of another galaxy, but were absorbed into our own. These are usually relatively recent events involving a much smaller galaxy.

But a new result changes that. By mapping huge numbers of stars in the galaxy, astronomers have found compelling evidence that the Milky Way ate a galaxy that was, at the time, about a quarter its size. And that time was a staggering ten billion years ago.

The stars in question were mapped by Gaia, a European Space Agency satellite. It is in the process of mapping the positions, motions, colors, and most importantly the distances of well over a billion stars. Yes, a billion.

Gaia has provided nothing short of a revolution in astronomy. How can mapping stars be so important? In some cases it can solve long-standing puzzles that have irritated astronomers for decades. In others it can reveal hidden denizens of the Milky Way. It can resolve uncertainties in distances to critical stars called Cepheids — like Polaris, the North Star — that are the bottom rung of the distance ladder, where each rung is a single step, but by the time you get to the top you’re measuring distances on a cosmic scale.

And in this new case, it reveals the remnants of a long-dead galaxy, one used as sustenance for our own.

Artwork depicting the stars from Gaia-Enceladus (arrows indicate their velocity) merging with the Milky Way based on actual physical simulations. Credit: ESA (artist’s impression and composition) Koppelman, Villalobos and Helmi (simulation) NASA/ESA/Hubble (galaxy image), CC BY-SA 3.0 IGO

What Gaia found was a vast stream of stars, 30,000 strong, that travel along similar orbits around the center of the Galaxy: highly elongated, tipped to the plane of the galaxy’s disk, and weirdly in a direction backward relative to other stars. This structure is so big that we’re actually inside it — literally, it surrounds the Sun in all directions — and can be seen stretching nearly across the entire sky. This stream is the remnant of the now-eaten galaxy.

The astronomers even gave that galaxy a name: Gaia-Enceladus, after the observatory that found it, of course, and the name of one of the Giants, which in Greek mythology were created when the Titan Cronus castrated his father Uranus and the blood was “received” (um, yeah) by the Earth-goddess Gaia. Yeah, I know, but Greek mythology is as gruesome as it is just plain weird. Anyway, the myth is a rough fit to what happened to the galaxy, so why not. My only complaint is that we already have a moon of Saturn named Enceladus, but given the relative scales they’re not likely to be confused with each other.

The structure of the Milky Way: A flattened disk with spiral arms (seen face-on, left, and edge-on, right), with a central bulge, a halo, and more than 150 globular clusters. The location of the Sun about halfway out is indicated. Credit: Left: NASA/JPL-Caltech right: ESA layout: ESA/ATG medialab

To understand why this is so important, picture the Milky Way: an enormous flat disk of stars, gas, and dust, with a central hub (a flattened bulge of stars in the very center) and all surrounded by a vast roughly spherical halo of stars as well.

If a smaller galaxy approaches us, our stronger gravity will start to stretch and eventually tear apart the smaller galaxy (because gravity gets weaker with distance, so the front of the smaller galaxy is pulled harder by the Milky Way than the back we call this effect tidal stretching). It may survive the first pass, but if it’s bound to us — that is, if it isn’t moving rapidly enough to escape — then it will orbit us, getting ripped apart over time.

The location of stars in the whole sky (mapped as an ellipse) from Gaia-Enceladus seen in the Gaia catalog. Color represents distance, with red closest and yellow farthest away. Circles are globular clusters, including, amazingly, Omega Centauri. Credit: ESA/Gaia/DPAC A. Helmi et al 2018

Sometime later all that’s left is an elliptical stream of stars, perhaps in a complete loop around the Milky Way. If the incoming galaxy were approaching at an angle to the disk, then so too will be the stream, and could even go around the center of the Milky Way in the opposite direction to the stars in the disk.

And that’s just what the observations found. Now, Gaia only found about 30,000 stars like this, but it can’t see all the way across the Milky Way, or get distances from stars that are too far away, so we’re only seeing a section of this stream. But it’s still pretty convincing if all the orbital characteristics weren’t enough, the stars also are chemically distinct from stars in our Milky Way, with a lot less iron in them than you see in “native” Milky Way stars. Also, using various indicators, the stars all appear to be roughly the same age, about 10 – 13 billion years old.

All of these are what you expect from a merger. Using the physics of how mergers behave, the astronomers created a simulation of what the collision and merger looked like:

The best fit to what’s seen is a merger with a flattened galaxy about ¼ the size of the Milky Way at the time (our galaxy is much larger now after lots more cannibalizing events) getting torn apart and eaten about 10 billion years ago. It came in at a 30-60° angle, and after all these eons what’s left of it is this stream of stars.

The mighty Omega Centauri, the largest globular cluster orbiting the Milky Way. Credit: ESO/INAF-VST/OmegaCAM. Acknowledgement: A. Grado, L. Limatola/INAF-Capodimonte Observatory

And globular clusters, too: ancient collections of hundreds of thousands of stars packed into a small volume, held together by their mutual gravity. More than 150 globulars orbit the Milky Way, and over a dozen of them were also found on a similar trajectory to the star stream… including Omega Centauri. I actually gasped when I saw that in the research paper! Omega Cen is the largest globular cluster in the Milky Way, containing perhaps ten million stars. It’s easily visible to the naked eye from southern latitudes, and is so big it’s been conjectured to have once been the core of a long-dead galaxy that was eaten by the Milky Way.

Whoa. That’s a very big deal indeed. I’ve seen Omega Cen with my own eyes, and now I have to re-evaluate that observation in this light. It’s now significantly cooler.

As a bonus, this merger explains some other features seen in the Milky Way, too. For example, the disk of the Milky Way itself can be split into two components, the thin disk and the thick disk — which is descriptive enough. The reason part of the disk is thicker hasn’t been entirely clear, but a collision of this magnitude 10 billion years ago would explain it the energy added by the collision puffed up part of the original disk, creating a thicker component. There’s also an inner and outer halo, too, and the inner halo would be other debris from this collision that’s no longer in the star stream. It’s nice when a single simple hypothesis explains a lot of different observations.

What’s funny to me about all this is that as incredible as it is — the Milky Way ate a big galaxy billions of years ago! — it’s actually been more or less the accepted idea for some time there’s evidence of other stellar streams in the Milky Way from previous mergers with dwarf (smaller) galaxies. We just hadn’t seen evidence of this one until now. What strikes me the most about it is how long ago it happened. Ten billion years is a long, long time, and the Milky Way was pretty young back then. To still see evidence, so plainly and obviously once we had the tools, after so many eons is just amazing.

And that is why Gaia is a revolution in the making. There’s so much to see in our galaxy, and we just didn’t have the means to see it.


A new look at sunspots

NASA’s extensive fleet of spacecraft allows scientists to study the Sun extremely close-up—one of the agency’s spacecraft is even on its way to fly through the Sun’s outer atmosphere. But sometimes taking a step back can provide new insight.

In a new study, scientists looked at sunspots—darkened patches on the Sun caused by its magnetic field—at low resolution as if they were trillions of miles away. What resulted was a simulated view of distant stars, which can help us understand stellar activity and the conditions for life on planets orbiting other stars.

“We wanted to know what a sunspot region would look like if we couldn’t resolve it in an image,” said Shin Toriumi, lead author on the new study and scientist at the Institute of Space and Astronautical Science at JAXA. “So, we used the solar data as if it came from a distant star to have a better connection between solar physics and stellar physics.”

Sunspots are often precursors to solar flares—intense outbursts of energy from the surface of the Sun—so monitoring sunspots is important to understanding why and how flares occur. Additionally, understanding the frequency of flares on other stars is one of the keys to understanding their chance of harboring life. Having a few flares may help build up complex molecules like RNA and DNA from simpler building blocks. But too many strong flares can strip entire atmospheres, rendering a planet uninhabitable.

To see what a sunspot and its effect on the solar atmosphere would look like on a distant star, the scientists started with high-resolution data of the Sun from NASA’s Solar Dynamics Observatory and JAXA/NASA’s Hinode mission. By adding up all the light in each image, the scientists converted the high-resolution images into single datapoints. Stringing subsequent datapoints together, the scientists created plots of how the light changed as the sunspot passed across the Sun’s rotating face. These plots, which scientists call light curves, showed what a passing sunspot on the Sun would look like if it were many light-years away.

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“The Sun is our closest star. Using solar observing satellites, we can resolve signatures on the surface 100 miles wide,” said Vladimir Airapetian, co-author on the new study and astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “On other stars you might only get one pixel showing the entire surface, so we wanted to create a template to decode activity on other stars.”

The new study, published in the Astrophysical Journal, looked at simple cases where there is just one group of sunspots visible across the entire face of the Sun. Even though NASA and JAXA missions have continually gathered observations of the Sun for over a decade, these cases are quite rare. Usually there are either several sunspots—such as during the solar maximum, which we are now moving toward—or none at all. In all the years of data, the scientists only found a handful of instances of just one isolated sunspot group.

Studying these events, the scientists found the light curves differed when they measured different wavelengths. In visible light, when a singular sunspot appears at the center of the Sun, the Sun is dimmer. However, when the sunspot group is near the edge of the Sun, it’s actually brighter due to faculae—bright magnetic features around sunspots—because, near the edge, the hot walls of their nearly vertical magnetic fields become increasingly visible.

The scientists also looked at the light curves in X-ray and ultraviolet light, which show the atmosphere above the sunspots. As the atmospheres above sunspots are magnetically heated, the scientists found brightening there at some wavelengths. However, the scientists also unexpectedly discovered that the heating could also cause a dimming in the light coming from the lower temperature atmosphere. These findings may provide a tool to diagnose the environments of spots on the stars.

“So far we’ve done the best-case scenarios, where there’s only one sunspot visible,” Toriumi said. “Next we are planning on doing some numerical modeling to understand what happens if we have multiple sunspots.”

By studying stellar activity on young stars in particular, scientists can glean a view of what our young Sun may have been like. This will help scientists understand how the young Sun—which was overall more dim but active—impacted Venus, Earth and Mars in their early days. It could also help explain why life on Earth started four billion years ago, which some scientists speculate is linked to intense solar activity.

Studying young stars can also contribute to scientists’ understanding of what triggers superflares—those that are 10 to 1000 times stronger than the biggest seen on the Sun in recent decades. Young stars are typically more active, with superflares happening almost daily. Whereas, on our more mature Sun, they may only occur once in a thousand years or so.

Spotting young suns that that are conducive to supporting habitable planets, helps scientists who focus on astrobiology, the study of the origin evolution, and distribution of life in the universe. Several next generation telescopes in production, which will be able to observe other stars in X-ray and ultraviolet wavelengths, could use the new results to decode observations of distant stars. In turn, this will help identify those stars with appropriate levels of stellar activity for life—and that can then be followed up by observations from other upcoming high-resolution missions, such as NASA’s James Webb Space Telescope.

Provided by: NASA’s Goddard Space Flight Center

More information: Shin Toriumi et al. Sun-as-a-star Spectral Irradiance Observations of Transiting Active Regions. The Astrophysical Journal (2020)

Image: One of the largest sunspots seen in early January 2014, as captured by NASA’s Solar Dynamics Observatory. An image of Earth has been added for scale.


The Sun, Sunspots and Consciousness

What role does the Sun and sunspots play on consciousness and how does this relate to our ever day lives?

Edgar Cayce wrote about the correlation between sunspots and consciousness:

Cayce saw sun spots, as well as earth changes as a reflection of our own state of consciousness, a result of our own actions, the boomerang of divine law. His readings offer simple metaphors to describe that eternal truth.

When asked about how sunspots affect the inhabitants of the earth, he said that the question should be reversed. Sunspots, he claimed, are reflection of the “turmoils and strifes” that we our selves have created, and our own mind is “the builder.” He asked us to think about what we have built:

As what does thy soul appear? A spot, a blot up the sun? Or as that which giveth light unto those who sit in darkness, to those who cry aloud for hope?13

Cayce said that the responsibility for earth changes lies squarely on our shoulders, and how we conduct our relationships with others has everything to do with the changing face of the earth:

Tendencies in the hearts and souls of men are such that these [earth changes] may be brought about….

As ye do it unto thy fellow man, ye do it unto thy God, to thyself.14

A bit like Hamlet, who lamented that “the time is out of joint,” Cayce talked about earth changes as “readjustments”—adjustments that have to be made because something is out of alignment. Yet Cayce believed that just as we create chaotic conditions by our own out of alignment behavior, so we can create positive transformation by our loving attitudes and actions.

“In the final sequence of his life,” writes author Jess Stearn in his book Edgar Cayce on the Millenium,

“the great prophet saw the relationship of man to his Creator as more tangible and consequential than any El Nino or eruption of the earth.”15

Cayce said that we are not ruled by the world, our environment or even

“planetary influences,” but by our own free will. When we disregard divine law, we ring “chaos and destructive forces” into our life when we are in harmony with the divine, we create order out of chaos.”16″

13. Edgar Cayce, Reading #5757-1

14. Hugh Lynn Cayce, Earth Changes Update, pp. 106, 105.

15. Jess Stearn, Edgar Cayce on the Millennium (New York Warner Books, 1998), p. 192

16. Edgar Cayce, quoted in Hugh Lyn Cayce, Earth Changes Update, p. 106.

While the scientific community has discovered a 13 year cycle for sunspots, wayshowers from the metaphysical community has been commenting on these events since the 1920’s:

“Observe the indications of seismographic curves. The points are disposed not along the equator, nor along a meridian, but form their own curves. Sometimes an increased activity of quakes and shiftings coincides with the intensity of so-called sun-spots resulting from a tension of the solar system. One need not be a prophet to understand that brain action in these periods will flow in a specific way.”

New Era Community (1926) #161.

“The full moon usually is favorable for telepathy. But there are other factors that affect it too. Most important, it is influenced by certain phases of the sunspots. You may yourself have noticed that telepathic manifestations grow stronger with the increased chemical activity of the lunar and planetary rays, but sunspots also affect many other aspects of existence. Cold, which can reach disastrous extremes, the heat of volcanic eruptions, and earthquakes follow changes in the solar aura. One must keep this in mind, because the cold may increase and the earthquakes become more powerful. Thus, a transitory solar manifestation can be terminal on Earth.”

“The function of the rays is contained in the blending of all energies with the Fire of Space. If one could resolve the Solar Ray into its electrons, it may be found to contain all elements that are in the cosmic, manifested, ray. The creativeness of the cosmic ray lies in the attraction and dissolution of energies. If the molecular particles could be extracted from the ray, their attraction could be utilized. Hence, one must adjust the forces of receptivity. Only striving from both ends will afford the necessary tension. Explosion occurs because of non-coordination of energies. All chaotic manifestations are only evidence of non-coordination. It may be said then that the tensive power of the cosmic ray is attracted toward Earth but meets with no responding vibration. Yet upon this foundation are all creative manifestations built. The affirmation of the cosmic ray intensifies all activity.”

The following is from an article, “Is the Sun Conscious?”:

For me, one of the most astonishing thoughts was rather casually advanced by David Lorimer, director of the Scientific and Medical Network. He told us that in August, 1997 the followers of the Bulgarian teacher Peter Dhunov, would be gathering in Bulgaria to commune with the spirit of their deceased master and other illuminated beings who would be meeting in the Sun at the same time!

Satish Kumar told us of the traditional Indian belief that the departed spirits of enlightened human beings pass first into the light of the Sun and then to dimensions or realms beyond the Sun was a kind of gateway through which human consciousness could move after bodily death.

Santos Bonacci covers in great detail the relationship between the sun and consciousness:

Astrotheology is the holy science that combines astrology, astronomy and theology. This holy science shows that in fact all myths, all story’s, the bible and all other holy scriptures, and even nursery rhymes are based on the movement and interaction of the seven lights we see in the sky. These seven lights we know as the Sun, the Moon, Mercury, Venus, Mars, Jupiter and Saturn. They are the lights our eyes can see wandering in front of the fixed background of the stars. These are the main characters that create patterns in the sky, which have an effect on our lives here on Earth or Terra. “As above, so below”.

The brightest of these seven lights is the Sun also know as “Helios” in Greece and as “Helios Atum” in ancient Egypt. “Atum” sounds like “atom” and it is in fact the same because the sun is an atom. It has an electric light core and electron bodies floating around it.

Plato said that the Sun is “the cause of our knowledge, without it we cannot see”. So the Sun is the teacher of the sense of the sight and the ruler of our eyes. The Sun is the “lucent” one, or “Lucifer”.

In ancient Egyptian mythology, the name of the “Sun” god was “Ra”, the one who “ra”diates. In churches, you will often see the letters “IHS” on books, altars, baptismal fonts etc. alwayspictured with a symbol of the sun around it. IHS stands for the Greek letters “iota”, “eta” and“sigma”. Writing in our alphabet, “IHS” equals “JHS” or “JHC”. The pronunciation of thisword is “JES”, which is a shorthand for “Jesus”. Jesus and the sun are the same. Jesus is thesun! Jesus Christ is God’s sun. The sun is the risen savior. So this “IHS” is a Christogram, amonogram which is an abbreviation of the name of “Jesus”. The early Christians were called:“Helionostics” which means “Those who have knowledge of the Sun”.

In Hebrew “yes”, or “jes” means fire or the sun! The name of the sun in Hebrew is Michael, or Emanuel. In India, it is: Krishna, Brahma, Shiva or Jes-Christna. In Egypt, it is: Ra, Horus, Seth, Atum, Aman. In the “Nag Hammadi” teachings is written that: “Christ is the true life and the sun of life”.

St Patrick (390 AD): “The true Christ is the sun “. Predulian (363 AD): “The sun is the center of the solar system”.

Eraneus: “The Gnostics really declared that all the supernatural transactions in the gospels were counterparts of what took place in the sky and heavens”.

Leonardo Davinci: “I could wish that I had such power of language as should avail me to assure those who would set the worship of man above that of the sun. Those who wish to worship man (an historical Christ) make a huge error!”

In the bible, Jesus says: “I’m the light of the world, every eye will see me”.

Bible – Simon: “For the Lord God is a sun and a shield”.

Bible – Psalm 48: 11: “The Lord is a shield and a sun”.

Bible – John 4: 8: “God is love”.

Bible – John 1: 5: “God is light: .

Bible – Hebrews 12: 12: “For our God is a consuming fire”.

Many people refuse to acknowledge the importance of the sun in esoteric terms. The Sun is not only the bringer of life, but is intimately connected to our consciousness as our bodies are a reflection of the cosmos. During sunspot activity, take notice of your emotions, health and mental well-being as these are all being affected on a deeper level. The more you become in tune with these occurrences, the more you will begin to see and understand the relationships between the sun, the cosmos and yourself.