Astronomy

Data on the composition and orbits of asteroids

Data on the composition and orbits of asteroids


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I am interested in the composition of asteroids from the perspective of determining potential targets for mining.

I expect there already exists some data that can be used to identify reasonable targets for mining.

The specific mining method I am looking to evaluate is to send a "collector" out and "grab" a target, bringing it back into LEO for mineral extraction. Because of this I would like to identify targets that are < 20m diameter. The ideal material to mine/extract would be a precious metal of some kind. This would give the most "bang for the buck". (The buck in this case being the effort rather than Delta V).
Considering the ideal material, I suspect a list of "M" type asteroids and their properties would be the data I am after.

I saw a question that asked about using IR Spectroscopy to determine the surface composition of asteroids. That gave some good insight - but no indication of where such data currently exists. A table of this data would be a reasonable starting point.

I am also wondering if we can determine anything about the relative density of an asteroid by the gravity it exerts on nearby objects. If that data is available anywhere that would also be an interesting place for me to look.

I am also interested in trying to determine the orbits of any target asteroids, so where would I look for data on the orbits of those that are selected?


The JPL Small-Body Database Search Engine is a good place to start. If diameter < 20 m, then probably absolute magnitude H > 25. Fortunately we know of over 4000 asteroids in that size range, mostly after close approaches to Earth. Unfortunately the orbit and magnitude are all we know about most of those, due to limited observational data. JPL SBDB lists only about 40 asteroids with known Tholen spectral type M, all with perihelion q > 1.5 AU and diameter > 30 km. The picture is a little brighter for type S, with over 300 known, a few with diameter < 2 km and minimum orbit intersection distance < 50 LD.


So I have just found this database - which looks like exactly what I was after!

It has over ½ a million asteroids listed - giving their value and cost to get them as well as a graphical representation of their orbit!

From the Website's description:

Details on orbits and basic physical parameters are sourced from the Minor Planet Center and NASA JPL. Composition data is based on spectral classification and size.


Asteroids

On the first day of January 1801, Giuseppe Piazzi discovered an object which he first thought was a new comet. But after its orbit was better determined it was clear that it was not a comet but more like a small planet. Piazzi named it Ceres, after the Sicilian goddess of grain. Three other small bodies were discovered in the next few years (Pallas, Vesta, and Juno). By the end of the 19th century there were several hundred.

Several hundred thousand asteroids have been discovered and given provisional designations so far. Thousands more are discovered each year. There are undoubtedly hundreds of thousands more that are too small to be seen from the Earth. There are 26 known asteroids larger than 200 km in diameter. Our census of the largest ones is now fairly complete: we probably know 99% of the asteroids larger than 100 km in diameter. Of those in the 10 to 100 km range we have cataloged about half. But we know very few of the smaller ones there are probably considerably more than a million asteroids in the 1 km range.

The total mass of all the asteroids is less than that of the Moon.

11 comets and asteroids have been explored by spacecraft so far, as follows: ICE flyby of Comet Giacobini-Zinner. Multiple flyby missions to Comet Halley. Giotto (retarget) to Comet Grigg-Skellerup. Galileo flybys of asteroids Gaspra and Ida (and Ida satellite Dactyl). NEAR-Shoemaker flyby of asteroid Mathilde on the way to orbit and land on Eros. DS-1 flybys of asteroid Braille and Comet Borrelly. Stardust flyby of asteroid Annefrank and recent sample collection from Comet Wild 2. For future we can expect: Hayabusa (MUSES-C) to asteroid Itokawa, Rosetta to Comet Churyumov-Gerasmenko, Deep Impact to Comet Tempel 1, and Dawn to orbit asteroids Vesta and Ceres.

243 Ida and 951 Gaspra were photographed by the Galileo spacecraft on its way to Jupiter. The NEAR mission flew by 253 Mathilde (left) on 1997 June 27 returning many images. NEAR (now renamed "NEAR-Shoemaker") entered orbit around 433 Eros (right) in January 1999 and returned a wealth of images and data. At the end of its mission it actually landed on Eros.

The largest asteroid by far is 1 Ceres. It is 933 km in diameter and contains about 25% of the mass of all the asteroids combined. The next largest are 2 Pallas, 4 Vesta and 10 Hygiea which are between 400 and 525 km in diameter. All other known asteroids are less than 340 km across.

There is some debate as to the classification of asteroids, comets and moons. There are many planetary satellites that are probably better thought of as captured asteroids. Mars's tiny moons Deimos and Phobos, Jupiter's outer eight moons, Saturn's outermost moon, Phoebe, and perhaps some of the newly discovered moons of Saturn, Uranus and Neptune are all more similar to asteroids than to the larger moons. (The composite image at the top of this page shows Ida, Gaspra, Deimos and Phobos approximately to scale.)

  • C-type, includes more than 75% of known asteroids: extremely dark (albedo 0.03) similar to carbonaceous chondrite meteorites approximately the same chemical composition as the Sun minus hydrogen, helium and other volatiles
  • S-type, 17%: relatively bright (albedo .10-.22) metallic nickel-iron mixed with iron- and magnesium-silicates
  • M-type, most of the rest: bright (albedo .10-.18) pure nickel-iron.
  • There are also a dozen or so other rare types.

There is little data about the densities of asteroids. But by sensing the Doppler effect on radio waves returning to Earth from NEAR owing to the (very slight) gravitational tug between asteroid and spacecraft, Mathilde's mass could be estimated. Surprisingly, its density turns out to be not much greater than that of water, suggesting that it is not a solid object but rather a compacted pile of debris.

  • Main Belt: located between Mars and Jupiter roughly 2 - 4 AU from the Sun further divided into subgroups: Hungarias, Floras, Phocaea, Koronis, Eos, Themis, Cybeles and Hildas (which are named after the main asteroid in the group).
  • Near-Earth Asteroids (NEAs): ones that closely approach the Earth
      : semimajor axes less than 1.0 AU and aphelion distances greater than 0.983 AU : semimajor axes greater than 1.0 AU and perihelion distances less than 1.017 AU : perihelion distances between 1.017 and 1.3 AU
  • There also a few "asteroids" (designated as "Centaurs") in the outer solar system: 2060 Chiron (aka 95 P/Chiron) orbits between Saturn and Uranus the orbit of 5335 Damocles ranges from near Mars to beyond Uranus 5145 Pholus orbits from Saturn to past Neptune. There are probably many more, but such planet-crossing orbits are unstable and they are likely to be perturbed in the future. The composition of these objects is probably more like that of comets or the Kuiper Belt objects than that of ordinary asteroids. In particular, Chiron is now classified as a comet.

    4 Vesta has been studied recently with HST (left). It is a particularly interesting asteroid in that it seems to have been differentiated into layers like the terrestrial planets. This implies some internal heat source in addition to the heat released by long-lived radio-isotopes which alone would be insufficient to melt such a small object. There is also a gigantic impact basin so deep that it exposes the mantle beneath Vesta's outer crust.

    Though they are never visible with the unaided eye, many asteroids are visible with binoculars or a small telescope.


    Amateur astronomers to 'Target Asteroids!'

    (Phys.org) -- Researchers on NASA's robotic asteroid sample return mission, OSIRIS-REx, are turning to amateur astronomers for new data on near-Earth asteroids in a citizen science observing campaign called Target Asteroids!

    Amateur astronomers are about to make observations that will affect current and future space missions to asteroids.

    Some will use custom-made, often automated telescopes equipped with CCD cameras in their backyards. Others will use home computers to make remote observations with more powerful telescopes states or continents away. Many belong to leading national and international amateur astronomy organizations with members ranging from retirees to school kids.

    Researchers on NASA's robotic asteroid sample return mission, OSIRIS-REx, are turning to amateur astronomers for new data on near-Earth asteroids in a citizen science observing campaign called Target Asteroids! The campaign starts in this month and will last at least to the end of this decade.

    The full name of the OSIRIS-REx mission is Origins Spectral Interpretation Resource Identification Security – Regolith Explorer. The OSIRIS-REx spacecraft is to launch in 2016, reach a well-characterized primitive asteroid called 1999 RQ36 in 2019, examine that body up close during a 505-day rendezvous, then return at least 60 grams of it to Earth in 2023.

    "Asteroids are a rich and accessible historic archive of the origin of our solar system and life, a valuable source of mineral resources, and potentially hazardous Earth impactors that civilization must learn to deal with," said OSIRIS-REx Principal Investigator Dante Lauretta of the University of Arizona. "Our mission will address all these issues."

    1999 RQ36 – a 500-meter-diameter, dark carbonaceous asteroid – is difficult for even powerful Earth-based telescopes to observe at this time because it is distant from Earth.

    Amateur astronomers are asked to observe asteroids selected because they are in near-Earth orbits that can be reached by current-generation spacecraft and are at least 200 meters in diameter, said Target Asteroids! scientist Carl Hergenrother, head of the OSIRIS-REx astronomy working group. 

    Precise orbits, sizes, rotation rates, physical composition and other important characteristics for these asteroids are largely unknown. Seventy-four asteroids are listed now, but the list will grow as observers get more information on known asteroids and discover new ones, Hergenrother said.

    Asteroid 2005 YU55 11/08/12. Credit: UA/LPL/Catalina Sky Survey/R. Hill

    "We want amateur astronomers to do astrometry (which precisely measures positions of objects), photometry (which measures brightness) and spectroscopy (which measures the colors, or wavelengths, of light) to discover as much as we can about these objects," he said.

    "These will be challenging objects to observe because they are very faint," said Target Asteroids! coordinator Dolores Hill of the OSIRIS-REx education and public outreach program.  "Amateur astronomers may have to make what are called ‘track and stack' observations," a technique that acquires and adds multiple short images.

    "One of the major goals of having amateur astronomers on board is they can observe these objects every night, unlike professional astronomers who may get to telescopes once every few nights, or more typically once a month or every three months," Hergenrother said.

    People don't need to own their own telescopes or live under clear skies to work on Target Asteroids!, Hergenrother and Hill emphasized.

    For not much money, observers can now go online and sign up to use a growing network of quality robotic telescopes sited at some of the choicest astronomical spots in the country, they added.

    Scientists will compare data from amateur and professional astronomers' ground-based observations with data from OSIRIS-REx spacecraft instruments to learn more about Earth-crossing asteroids and identify likely candidates for future asteroid missions, they said.

    "The OSIRIS-REx mission truly is a ‘ground truth' mission, the connection between meteorites on the ground and asteroids that are still orbiting the sun that could hit the ground," Hill said.

    Amateur astronomer observers like Tim Hunter will compile information about asteroids. These observations directly support NASA’s OSIRIS-REx asteroid sample return mission and aid future mission designers and scientists. Citizen scientists' astronomy and photometry data will enable scientists to refine orbits, test models of the dynamical evolution and determine the composition of these objects. Credit: Tim Hunter

    Not long ago, astronomers disparaged asteroids as the "vermin of the skies," said Ed Beshore, OSIRIS-REx deputy principal investigator. Astronomers saw asteroids as bothersome "noise," unwanted streaks of light that contaminated their photographic views of celestial objects farther out in the cosmos.

    That thinking changed when people realized how much damage near-Earth asteroids can do when they hit Earth as meteorites, Beshore said.

    For example, sophisticated mathematical modeling shows that the chunk of meteorite that blasted 1.25-kilometer-wide Meteor Crater out of northern Arizona's Colorado Plateau about 50,000 years ago was less than 70 meters wide. Granted, that space rock was a rare iron-nickel meteorite that carried a much greater wallop than a stony or carbonaceous meteorite of the same size would have had. But still, that's impressive.

    Until Beshore was named OSIRIS-REx deputy principal investigator earlier this year, he directed the UA's Catalina Sky Survey. This NASA-funded survey has led the world in searching for potentially hazardous NEOs, or near-Earth objects, since 2005. Amateur astronomers have helped enormously by providing follow-up observations that find orbits of newly discovered asteroids, Beshore said.

    "Amateur astronomy today is much different than it was, say, even in the mid-1990s," Beshore said. "The amateur astronomy community working now is extremely sophisticated. They have more advanced computers. They have developed a tremendous number of turnkey solutions to automate their telescopes. And they now can rent telescopes larger than most amateurs can afford.

    "You've got a lot of dedicated amateurs out there who really are working like professionals, making serious contributions to the field," he said.

    "Frankly, if they wanted to, many could probably get jobs as professionals. But they're probably making more money doing what they're doing at their day jobs."

    Target Asteroids! partner organizations so far include:

    • The International Astronomical Search Collaboration, or IASC. The IASC is an educational outreach program that provides free, donated telescope time to amateur astronomers from 30 high schools and colleges in five countries for asteroid observations. Students in the U.S. and Poland already are analyzing results on one of the Target Asteroids! that IASC members made using a 1.3-meter telescope at Kitt Peak National Observatory near Tucson last February.

    • Astronomical League. An umbrella organization of about 140 amateur astronomy organizations across the U.S. Based in Kansas City, Mo., it promotes astronomy by encouraging public interest via local astronomy clubs.

    • Association of Lunar & Planetary Observers. Founded in 1947, this organization facilitates research by both professional and amateur astronomers working in lunar, planetary and solar astronomy. Members and section coordinators are scattered all over the world.

    • Oceanside Photo and Telescope, or OPT. One of the largest telescope retailers in the world, based in Oceanside, Calif., OPT provides technical expertise and astronomy equipment to educators and organizations across the country.

    • NASA Night Sky Network is a nationwide coalition of amateur astronomy clubs that provide information about NASA missions and host astronomy events for the general public. The Night Sky Network is sponsored and supported by the NASA Jet Propulsion Laboratory's PlanetQuest program.

    • University of Arizona Mt. Lemmon SkyCenter. This UA science center is located where astronomical seeing is outstanding, at the 9,200-foot summit of Mount Lemmon in the Santa Catalina Mountains north of Tucson. It offers both nightly public astronomy programs and opportunities for remote observing using the 32-inch Schulman telescope and 24-inch Beshore telescope. The SkyCenter is a partner in the Sierra Stars Observing Network, a widening network of professional observatories working to make advanced imaging capabilities available to amateur astronomers at modest cost.

    • The Catalina Sky Survey, UA Lunar and Planetary Laboratory. The Catalina Sky Survey has been the most successful near-Earth object survey for several years running. This survey discovered 586 near-Earth asteroids, or 65 percent of all NEO discoveries made in 2011. In fall 2008, CSS scientists became the first to observe an asteroid on a collision course with the Earth, allowing that object to be tracked and eventually recovered as meteorites in the Sudan's Nubian Desert.


    Elementary Astronomy (107)

    We've seen that asteroids are most commonly found outside the orbit of Mars and inside the orbit of Jupiter, in a donut-shaped torus that even goes out of the plane of the solar system. Their low mass and close encounters with one another, plus the effects of Jupiter, send then occasionally careening inward. A few are found in so-called near Earth orbits and present a hazard for us because of the very high energy they have.



    Asteroids have different compositions that may be traced to their origins. Some are fluffy, some icy, and some very dense and largely metallic. In a few instances we have direct observations from satellites, and for others we have to infer their composition form the light they reflect or by associating them with similar ones that have hit the Earth and left remnants. There is speculation that many asteroids will be valuable resources for materials that are rare on Earth. While the cost of accessing them is high, for those that have a velocity similar to Earth the "value" is speculatively astronomical. This website will give you a tour and show the orbits of the known asteroids accurately.


    An Asteroid Nearby from Another Star?

    One, found in November 2017, has an unbound orbit. It is the first object we have ever seen like that. Even comets coming from the Oort Cloud have orbits that are very weakly bound to the Sun such that at their greatest distance they hardly move at all. Oumuamua, however, passed us at 18 km/s (40,000 miles per hour). NASA's website has an in-depth look at what we know about it now.

    Since its discovery we observed that it changed its motion in a way that could not easily be explained if it is giving off gasses, as comets do, and its acceleration was large, implying that it is not very massive. If Oumuamua is not a completely rocky asteroid from another star, it could be a comet from outside our solar system. Or something else? Avi Loeb, an astronomy professor at Harvard, thinks we need to consider that it could be an alien spacecraft flying by to take a look at us. Most astronomers are not ready yet to take that leap.

    Missions to Asteroids

    Asteroids are of interest for future space missions as a test for our ability to work beyond Earth's neighborhood.

    The NASA robotic mission OSIRIS-REx will travel to the the near-Earth asteroid Bennu after its successful launch on Thursday, September 8, 2016. It reached the asteroid in 2018, is in orbit around it, and and has taken images. As of January 2019, the best one is this composite


    It will bring a piece of it back to Earth 5 years later, in 2023. The link

    is to the NASA website, and the mission website is

    Additional factual detail about the project is in Wikipedia

    The New York Times Science editor Dennis Overbye describes the mission to bring a piece of Bennu back to the Utah desert in 2023.

    The Japanese space agency JAXA sent a sample return mission Hayabusa 2 to the asteroid Ryugu and it brought back material from the asteroid that was recovered when the return spacecraft landed in the Australian outback in December 2020. The mission carefully planned to keep the material isolated from contamination and it is currently being studied. One unexpected feature is how very dark it is.


    Vesta: A Differentiated Asteroid

    Vesta is one of the most interesting of the asteroids. It orbits the Sun with a semi-major axis of 2.4 AU in the inner part of the asteroid belt. Its relatively high reflectivity of almost 30% makes it the brightest asteroid, so bright that it is actually visible to the unaided eye if you know just where to look. But its real claim to fame is that its surface is covered with basalt, indicating that Vesta is a differentiated object that must once have been volcanically active, in spite of its small size (about 500 kilometers in diameter).

    Meteorites from Vesta&rsquos surface (Figure (PageIndex<3>)), identified by comparing their spectra with that of Vesta itself, have landed on Earth and are available for direct study in the laboratory. We thus know a great deal about this asteroid. The age of the lava flows from which these meteorites derived has been measured at 4.4 to 4.5 billion years, very soon after the formation of the solar system. This age is consistent with what we might expect for volcanoes on Vesta whatever process heated such a small object was probably intense and short-lived. In 2016, a meteorite fell in Turkey that could be identified with a particular lava flow as revealed by the orbiting Dawn spacecraft.

    Figure (PageIndex<3>) Piece of Vesta. This meteorite (rock that fell from space) has been identified as a volcanic fragment from the crust of asteroid Vesta.


    Going Beyond

    When NEOs occasionally fly past us, usually well beyond the moon's orbit, they move across the sky very rapidly, showing movement against the stars over the course of just a few minutes. Most of these are far too small to see visually, or with small telescopes, but a rare few are large enough. Asteroid Tracker for Android and iOS is an app that lists the upcoming passes, including the object's name, closest distance and mass. It also lists the predicted impact hazard level. The website Slooh.com frequently streams live broadcasts of the passes as well as many other interesting astronomical events, complete with video feeds through telescopes and commentary by experts.

    In future editions of mobile astronomy, we'll look at photographing objects with your smartphone, some cool astronomy virtual-reality apps and hardware, how to use astronomy apps in the classroom and more. Until then, keep looking up!

    Editor's note: Chris Vaughan is an astronomy public outreach and education specialist, and operator of the historic 1.88 meter David Dunlap Observatory telescope. You can reach Chris via email, and follow him on Twitter @astrogeoguy, as well as Facebook and Tumblr.


    NEO Basics

    Near-Earth Objects (NEOs) are comets and asteroids that have been nudged by the gravitational attraction of nearby planets into orbits that allow them to enter the Earth’s neighborhood. Composed mostly of water ice with embedded dust particles, comets originally formed in the cold outer planetary system while most of the rocky asteroids formed in the warmer inner solar system between the orbits of Mars and Jupiter. The scientific interest in comets and asteroids is due largely to their status as the relatively unchanged remnant debris from the solar system formation process some 4.6 billion years ago. The giant outer planets (Jupiter, Saturn, Uranus, and Neptune) formed from an agglomeration of billions of comets and the left over bits and pieces from this formation process are the comets we see today. Likewise, today’s asteroids are the bits and pieces left over from the initial agglomeration of the inner planets that include Mercury, Venus, Earth, and Mars.

    As the primitive, leftover building blocks of the solar system formation process, comets and asteroids offer clues to the chemical mixture from which the planets formed some 4.6 billion years ago. If we wish to know the composition of the primordial mixture from which the planets formed, then we must determine the chemical constituents of the leftover debris from this formation process - the comets and asteroids.


    Astrometry and Orbits of Asteroids and Comets

    Astronomers have been consciously making positional observations of comets since the sixteenth century, and rough information on bright comets is available from social records collected in the Far East, the Middle East and Europe over the previous two millennia. Attempts at representing the observations with orbits also date back to the sixteenth century, well before the earliest computations were made on the basis of gravitational theory. Improvement in the accuracy of cometary astrometric data was slow to develop following the invention of the telescope and, a few decades later, the micrometer, for this had to await the availability of Flamsteed’s star catalogue and the understanding brought about by Bradley’s discovery of aberration and nutation. In spite of important contributions by some of the most celebrated scientists of the eighteenth century, orbit computation remained largely a process of trial and error until the discovery of the first asteroids and the rise of Gauss and his followers. By the 1880s the availability of a dense star catalogue like the AGK1 was allowing micrometric observations of comets and asteroids often to achieve an accuracy of 2 to 3 arcsec, and the subsequent introduction of photographic astrometry brought convenience but relatively little additional improvement in accuracy. The use nowadays of charge-coupled devices clearly has the potential for a further increase in accuracy, even for diffuse objects like comets, but for the moment the accuracy tends generally to be limited by the inadequacy of the available star catalogues. Modern orbit determination routinely includes the use of sophisticated techniques to identify isolated observations of the same asteroid at different oppositions and in the case of a comet the examination of the nongravitational effects that can strongly influence the object’s motion.


    Astronomer Discover Asteroids Orbits Closer To Sun Than Venus

    that orbit closer to the Sun than Venus does. The problem is, nobody’s been able to find one. Until now.

    Astronomer working with the Zwicky Transient Facility say they’ve finally found one. But this one’s bigger, at about 2 km. If its existence can be confirmed, then asteroid population models may have to be updated.

    A new paper presenting this result is up on arXiv, a pre-press publication site. It’s titled “A kilometer-scale asteroid inside Venus’s orbit”. The lead author is Dr. Wing-Huen Ip, a Professor of Astronomy at the Institute of Astronomy, National Central University, Taiwan.

    The newly-discovered asteroid is named 2020 AV2, has an aphelion distance of only 0.65 astronomical units, and is about 2 km in diameter.

    Its discovery is surprising since models predict no asteroids this large inside Venus’ orbit. It could be evidence of a new population of asteroids, or it could just be the largest of its population.

    The authors write that: “If this discovery is not a statistical fluke, then 2020 AV2 may come from a yet undiscovered source population of asteroids interior to Venus, and currently favored asteroid population models may need to be adjusted.”

    There are about one million known asteroids, and the vast majority of them are well outside Earth’s orbit. There are only a tiny fraction located with their entire orbits inside Earth’s.

    Models predict that an even smaller number of asteroids should be inside Venus’ orbit. Those asteroids are called Vatiras.

    2020 AV2 was first spotted by the Zwicky Transient Facility (ZTF) on 4 January 2020. Follow-up observations with the Palomar 60-inch telescope and the Kitt Peak 84-inch ‘scope gathered more data.

    Near the end of January, astronomer used the Keck Telescope for spectroscopic observations of the rock. That data shows that the asteroid came from the inner region of the main asteroid belt, between Mars and Jupiter.

    “These data favor a silicate S-type asteroid-like composition consistent with an origin from the inner Main Belt where S-type asteroids are the most plentiful.” They add that it agrees with Near Earth Asteroid (NEA) models that “…predict asteroids with the orbital elements of 2020 AV2 should originate from the inner Main Belt.”

    2020 AV2 is either a model-buster or a model-confirmer.

    “NEA population models predict <1 inner-Venus asteroid of this size implying that 2020 AV2 is one of the largest inner-Venus asteroids in the Solar System,” the authors write.

    It’s either the largest one, which makes sense because the largest one would be the first to be spotted, or there are more of them that we haven’t found yet.

    The authors thought through two scenarios involving 2020 AV2’s detection, and what it means.

    “Despite its low probability, a possible explanation for our detection of 2020 AV2 is a random chance discovery from the nearEarth asteroid population,” they write.

    “However,” they continue, “history has shown that the first detection of a new class of objects is usually indicative of another source population c.f., such as the Kuiper Belt with the discovery of the first Kuiper Belt Objects 1992 QB1 and 1993 FW.”

    There’s also a possibility that 2020 AV2 didn’t originate in the main asteroid belt. Models show that there’s a region inside Mercury’s orbit that could have spawned asteroids, and where they might still reside. “…2020 AV2 could have originated from a source of asteroids located closer to the Sun, such as near the stability regions located inside the orbit of Mercury at

    0.1-0.2 au where large asteroids could have formed and survived on time scales of the age of the Solar System.”

    2020 AV2 might not spend an eternity on its present orbit. The team of researchers performed some simulations, and they show that the asteroid could be ejected from the Solar System entirely. “… dynamical N-body simulations of 2020 AV2 indicate that its orbit is stable on

    10 Myr timescales, entering into temporary resonances with the terrestrial planets and Jupiter before its orbit evolves onto close-encounter paths with the gas giant leading to its eventual ejection from the Solar System.”

    When 2020 AV2 was first discovered, scientists wondered at the journey it must have taken to get there. They also wondered about is eventual fate.

    “Getting past the orbit of Venus must have been challenging,” said George Helou, executive director of the IPAC astronomy center at Caltech and a ZTF co-investigator, in a press release.

    Helou explained that the asteroid must have migrated in toward Venus from farther out in the solar system.

    “The only way it will ever get out of its orbit is if it gets flung out via a gravitational encounter with Mercury or Venus, but more likely it will end up crashing on one of those two planets.”

    If this discovery is just the first of a whole population of asteroids inside Venus’ orbit, the majority of them will all share the same fate. After about 10 to 20 million years, they’ll all be ejected.


    Data on the composition and orbits of asteroids - Astronomy

    The scientific interest in asteroids is due largely to their status as the remnant debris from the inner solar system formation process. Because some of these objects can collide with the Earth, asteroids are also important for having significantly modified the Earth's biosphere in the past. They will continue to do so in the future. In addition, asteroids offer a source of volatiles and an extraordinarily rich supply of minerals that can be exploited for the exploration and colonization of our solar system in the twenty-first century.

    Asteroids represent the bits and pieces left over from the process that formed the inner planets, including Earth. Asteroids are also the sources of most meteorites that have struck the Earth's surface and many of these meteorites have already been subjected to detailed chemical and physical analyses. If certain asteroids can be identified as the sources for some of the well-studied meteorites, the detailed knowledge of the meteorite's composition and structure will provide important information on the chemical mixture, and conditions from which the Earth formed 4.6 billion years ago. During the early solar system, the carbon-based molecules and volatile materials that served as the building blocks of life may have been brought to the Earth via asteroid and comet impacts. Thus the study of asteroids is not only important for studying the primordial chemical mixture from which the Earth formed, these objects may hold the key as to how the building blocks of life were delivered to the early Earth.

    On a daily basis, the Earth is bombarded with tons of interplanetary material. Many of the incoming particles are so small that they are destroyed in the Earth's atmosphere before they reach the ground. These particles are often seen as meteors or shooting stars. The vast majority of all interplanetary material that reaches the Earth's surface originates as the collision fragments of asteroids that have run into one another some eons ago. With an average interval of about 100 years, rocky or iron asteroids larger than about 50 meters would be expected to reach the Earth's surface and cause local disasters or produce the tidal waves that can inundate low lying coastal areas. On an average of every few hundred thousand years or so, asteroids larger than a mile could cause global disasters. In this case, the impact debris would spread throughout the Earth's atmosphere so that plant life would suffer from acid rain, partial blocking of sunlight, and from the firestorms resulting from heated impact debris raining back down upon the Earth's surface. The probability of an asteroid striking the Earth and causing serious damage is very remote but the devastating consequences of such an impact suggests we should closely study different types of asteroids to understand their compositions, structures, sizes, and future trajectories.

    The asteroids that are potentially the most hazardous because they can closely approach the Earth are also the objects that could be most easily exploited for raw materials. These raw materials could be used in developing the space structures and in generating the rocket fuel that will be required to explore and colonize our solar system in the twenty-first century. By closely investigating the compositions of asteroids, intelligent choices can be made as to which ones offer the richest supplies of raw materials. It has been estimated that the mineral wealth resident in the belt of asteroids between the orbits of Mars and Jupiter would be equivalent to about 100 billion dollars for every person on Earth today.