Members Can Post Anonymously On This Site
Chelyabinsk a decade on: the Sun's invisible asteroids
-
Similar Topics
-
By NASA
5 Min Read What Are Asteroids? (Ages 14-18)
What are asteroids?
Asteroids are rocky objects that orbit the Sun just like planets do. In fact, sometimes asteroids are called “minor planets.” These space rocks were left behind after our solar system formed about 4.6 billion years ago.
Asteroids are found in a wide range of sizes. For example, one small asteroid, 2015 TC25, has a diameter of about 6 feet – about the size of a small car – while the asteroid Vesta is nearly 330 miles in diameter, almost as wide as the U.S. state of Arizona. Some asteroids even have enough gravity to have one or two small moons of their own.
There are more than a million known asteroids. Many asteroids are given names. An organization called the International Astronomical Union is responsible for assigning names to objects like asteroids and comets.
This illustration depicts NASA’s Psyche spacecraft as it approaches the asteroid Psyche. Once it arrives in 2029, the spacecraft will orbit the metal-rich asteroid for 26 months while it conducts its science investigation.NASA/JPL-Caltech/ASU What’s the difference between asteroids, meteors, and comets?
Although all of these celestial bodies orbit the Sun, they are not the same. Unlike asteroids, which are rocky, comets are a mix of dust and ice. Meteors are small space rocks that get pulled close enough to enter Earth’s atmosphere, where they either burn up as a shooting star or land on the ground as a meteorite.
What are asteroids made of?
Different types of asteroids are composed of different mixes of materials. Most of them are made of chondrites, which are combinations of materials such as rocks and clay. These are called “C-type” asteroids. Some, called “S-type,” are made of stony materials, while “M-type” asteroids are composed of metallic elements.
NASA’s Dawn spacecraft captured this image of Vesta as it left the giant asteroid’s orbit in 2012. The framing camera was looking down at the north pole, which is in the middle of the image.NASA/JPL-Caltech/UCLA/MPS/DLR/IDA How did the asteroids form?
Asteroids formed around the same time and in the same way as the planets in our solar system. A massive, dense cloud of gas and dust collapsed into a spinning disk, and the gravity in the disk’s center pulled more and more material toward it. Over time, these pieces repeatedly collided with each other, sometimes resulting in smaller fragments and other times clumping together, resulting in much bigger objects.
Objects with a lot of mass – like planets – produced enough gravity to pull themselves into spheres, but many smaller objects didn’t. These ended up becoming comets, small moons, and, yes, asteroids. Although some asteroids have a spherical shape, most have irregular shapes – sometimes oblong, bumpy, or jagged.
The main asteroid belt lies between Mars and Jupiter, and Trojan asteroids both lead and follow Jupiter. Scientists now know that asteroids were the original “building blocks” of the inner planets. Those that remain are airless rocks that failed to adhere to one another to become larger bodies as the solar system was forming 4.6 billion years ago.Credits: NASA, ESA and J. Olmsted (STScI) Where are asteroids found?
Most of the asteroids we know about are located in an area called the main asteroid belt, which is found in the space between Mars and Jupiter. But asteroids are found in other parts of the solar system, too.
Trojan asteroids orbit the Sun on the same orbital path as a planet. They’re found at two specific points on the planetary orbit called Lagrange points. At these points, the gravitational pull of the planet and the Sun are in balance, making these points gravity-neutral and stable. Many planets have been found to have Trojan asteroids, including Earth.
An asteroid’s location can also be influenced by the gravity of planets it passes and end up pushed or pulled onto a path that brings it close to Earth. When asteroids or comets are on an orbital path that comes within 30 million miles of Earth’s orbit, we call them near-Earth objects.
Illustration of NASA’s DART spacecraft and the Italian Space Agency’s (ASI) LICIACube, with images of the asteroids Dimorphos and Didymos obtained by the DART spacecraft.Credit: NASA/Johns Hopkins APL/Joshua Diaz Could an asteroid come close enough to hit Earth?
Yes! Throughout history, asteroids or pieces of asteroids have collided with Earth, our Moon, and the other planets, too. The effects of some of these impacts are still visible. For example, Chicxulub Crater was created 65 million years ago when a massive asteroid struck Mexico’s Yucatan Peninsula. The resulting cloud of dust and gas released into Earth’s atmosphere blocked sunlight, leading to a mass extinction that included the dinosaurs. More recently, in 2013, people in Chelyabinsk, Russia, witnessed an asteroid almost as wide as a tennis court explode in the atmosphere above them. That event produced a powerful shockwave that caused injuries and damaged structures.
This is why NASA’s Planetary Defense Coordination Office keeps a watchful eye on near-Earth objects. The Planetary Defense team relies on telescopes and observatories on Earth and in space to detect and monitor objects like these that could stray too close to our planet.
The agency is working on planetary defense strategies to use if an asteroid is discovered to be heading our way. For example, NASA’s DART (Double Asteroid Redirection Test) mission in 2022 was a first-of-its-kind test: an uncrewed spacecraft with an autonomous targeting system intentionally flew into the asteroid Dimorphos, successfully changing its orbit.
Jason Dworkin, OSIRIS-REx mission project scientist, holds up a vial containing part of the sample from asteroid Bennu in 2023.Credit: NASA/James Tralie How does NASA study asteroids?
NASA detects and tracks asteroids using telescopes on the ground and in space, radar observations, and computer modeling. The agency also has launched several robotic explorers to learn more about asteroids. Some missions study asteroids from above, such as the Psyche mission, launched in 2023 to study the asteroid Psyche beginning in 2029. Other missions have actually made physical contact with asteroids. For example, the DART mission mentioned above impacted an asteroid to change its orbit, and the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification and Security – Regolith Explorer) spacecraft collected a sample of material from the surface of asteroid Bennu and delivered the sample to Earth in 2023 for scientists to study.
Career Corner
Want a career where you get to study asteroids? Here are some jobs at NASA that do just that:
Astronomer: These scientists observe and study planets, stars, and galaxies. Astronomers make discoveries that help us understand how the universe works and how it is changing. This job requires a strong educational background in science, math, and computer science. Geologist: Asteroids are made of different types of rock, clay, or metallic materials. Geologists study the properties and composition of these materials to learn about the processes that have shaped Earth and other celestial bodies, like planets, moons, and asteroids. More About Asteroids
Asteroid Facts
Gallery: What’s That Space Rock?
Center for Near Earth Object Studies
Planetary Defense at NASA
Asteroid Watch: Keeping an Eye on Near-Earth Objects
View the full article
-
By USH
In recent months, Earth has been experiencing a string of bizarre and unsettling phenomena. Massive power outages have struck Spain and Portugal, with similar blackouts occurring across the globe. Aircraft have inexplicably crashed or fallen from the sky. Lights - streetlamps, billboards, car headlights, even indoor lighting are flickering erratically, and the problem persists.
Power failures have disrupted air traffic control centers. Strange, unexplained noises have been heard coming from the sky. In parts of the U.S., blue rain has reportedly fallen. The Schumann Resonance, Earth’s natural electromagnetic frequency, has spiked dramatically. Most disturbing of all, now birds have been seen suddenly dropping dead, either mid-flight or while perched on power lines.
It feels as if the planet is enveloped in a powerful, unseen force, an invisible energy field swarming the Earth, disrupting both man-made and natural systems. But where is it coming from?
One theory suggests that we may be experiencing the delayed impact of a massive astronomical event that occurred thousands of years ago, such as a supernova, the cataclysmic explosion of a dying star. These cosmic blasts release enormous amounts of electromagnetic radiation, including gamma rays and X-rays, which can travel across space for thousands or even millions of years before reaching other celestial bodies, like Earth.
Interestingly, some scientists have speculated that a gamma-ray burst from a distant supernova might have triggered the Ordovician mass extinction around 440 million years ago. If such radiation can wipe out entire ecosystems, could a similar event be silently influencing the strange phenomena we're seeing today?
It might sound improbable, but what if Earth is now being bathed in residual energy from a long-past cosmic event, energy that is only just now arriving and interacting with our atmosphere and technology?
And if that's true… could these strange occurrences be the early signs of something even more serious to come?
Additional: MrMBB333, a well-known YouTuber, is also closely following these remarkable events. He shares daily live footage from around the world and often questions what is truly happening. In his latest video below he shares the mystery of the birds dropping dead while perched on power lines.
You can watch his videos on his YouTube channel: https://www.youtube.com/user/MrMBB333/videosView the full article
-
By NASA
5 min read
How NASA Science Data Defends Earth from Asteroids
Artist’s impression of NASA’s DART mission, which collided with the asteroid Dimorphos in 2022 to test planetary defense techniques. Open science data practices help researchers identify asteroids that pose a hazard to Earth, opening the possibility for deflection should an impact threat be identified. NASA/Johns Hopkins APL/Steve Gribben The asteroid 2024 YR4 made headlines in February with the news that it had a chance of hitting Earth on Dec. 22, 2032, as determined by an analysis from NASA’s Center for Near Earth Object Studies (CNEOS) at the agency’s Jet Propulsion Laboratory in Southern California. The probability of collision peaked at over 3% on Feb. 18 — the highest ever recorded for an object of its size. This sparked concerns about the damage the asteroid might do should it hit Earth.
New data collected in the following days lowered the probability to well under 1%, and 2024 YR4 is no longer considered a potential Earth impactor. However, the event underscored the importance of surveying asteroid populations to reveal possible threats to Earth. Sharing scientific data widely allows scientists to determine the risk posed by the near-Earth asteroid population and increases the chances of identifying future asteroid impact hazards in NASA science data.
“The planetary defense community realizes the value of making data products available to everyone,” said James “Gerbs” Bauer, the principal investigator for NASA’s Planetary Data System Small Bodies Node at the University of Maryland in College Park, Maryland.
How Scientists Spot Asteroids That Could Hit Earth
Professional scientists and citizen scientists worldwide play a role in tracking asteroids. The Minor Planet Center, which is housed at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, collects and verifies vast numbers of asteroid and comet position observations submitted from around the globe. NASA’s Small Bodies Node distributes the data from the Minor Planet Center for anyone who wants to access and use it.
A near-Earth object (NEO) is an asteroid or comet whose orbit brings it within 120 million miles of the Sun, which means it can circulate through Earth’s orbital neighborhood. If a newly discovered object looks like it might be an NEO, information about the object appears on the Minor Planet Center’s NEO Confirmation Page. Members of the planetary science community, whether or not they are professional scientists, are encouraged to follow up on these objects to discover where they’re heading.
The asteroid 2024 YR4 as viewed on January 27, 2025. The image was taken by the Magdalena Ridge 2.4m telescope, one of the largest telescopes in NASA’s Planetary Defense network. Asteroid position information from observations such as this one are shared through the Minor Planet Center and NASA’s Small Bodies Node to help scientists pinpoint the chances of asteroids colliding with Earth. NASA/Magdalena Ridge 2.4m telescope/New Mexico Institute of Technology/Ryan When an asteroid’s trajectory looks concerning, CNEOS alerts NASA’s Planetary Defense Coordination Office at NASA Headquarters in Washington, which manages NASA’s ongoing effort to protect Earth from dangerous asteroids. NASA’s Planetary Defense Coordination Office also coordinates the International Asteroid Warning Network (IAWN), which is the worldwide collaboration of asteroid observers and modelers.
Orbit analysis centers such as CNEOS perform finer calculations to nail down the probability of an asteroid colliding with Earth. The open nature of the data allows the community to collaborate and compare, ensuring the most accurate determinations possible.
How NASA Discovered Risks of Asteroid 2024 YR4
The asteroid 2024 YR4 was initially discovered by the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) survey, which aims to discover potentially hazardous asteroids. Scientists studied additional data about the asteroid from different observatories funded by NASA and from other telescopes across the IAWN.
At first, 2024 YR4 had a broad uncertainty in its future trajectory that passed over Earth. As the planetary defense community collected more observations, the range of possibilities for the asteroid’s future position on Dec. 22, 2032 clustered over Earth, raising the apparent chances of collision. However, with the addition of even more data points, the cluster of possibilities eventually moved off Earth.
This visualization from NASA’s Center for Near Earth Object Studies shows the evolution of the risk corridor for asteroid 2024 YR4, using data from observations made up to Feb. 23, 2025. Each yellow dot represents the asteroid’s possible location on Dec. 22, 2032. As the range of possible locations narrowed, the dots at first converged on Earth, before skewing away harmlessly. NASA/JPL/CNEOS Having multiple streams of data available for analysis helps scientists quickly learn more about NEOs. This sometimes involves using data from observatories that are mainly used for astrophysics or heliophysics surveys, rather than for tracking asteroids.
“The planetary defense community both benefits from and is beneficial to the larger planetary and astronomy related ecosystem,” said Bauer, who is also a research professor in the Department of Astronomy at the University of Maryland. “Much of the NEO survey data can also be used for searching astrophysical transients like supernova events. Likewise, astrophysical sky surveys produce data of interest to the planetary defense community.”
How Does NASA Stop Asteroids From Hitting Earth?
In 2022, NASA’s DART (Double Asteroid Redirection Test) mission successfully impacted with the asteroid Dimorphos, shortening the time it takes to orbit around its companion asteroid Didymos by 33 minutes. Didymos had no chance of hitting Earth, but the DART mission’s success means that NASA has a tested technique to consider when addressing a future asteroid potential impact threat.
Artist’s impression of NASA’s upcoming NEO Surveyor mission, which will search for potentially hazardous near-Earth objects. The mission will follow open data practices to improve the chances of identifying dangerous asteroids. NASA/JPL-Caltech To increase the chances of discovering asteroid threats to Earth well in advance, NASA is working on a new space-based observatory, NEO Surveyor, which will be the first spacecraft specifically designed to look for asteroids and comets that pose a hazard to Earth. The mission is expected to launch in the fall of 2027, and the data it collects will be available to everyone through NASA archives.
“Many of the NEOs that pose a risk to Earth remain to be found,” Bauer said. “An asteroid impact has a very low likelihood at any given time, but consequences could be high, and open science is an important component to being vigilant.”
For more information about NASA’s approach to sharing science data, visit:
https://science.nasa.gov/open-science.
By Lauren Leese
Web Content Strategist for the Office of the Chief Science Data Officer
Share
Details
Last Updated Apr 10, 2025 Related Terms
Open Science Planetary Defense Explore More
2 min read Citizen Scientists Use NASA Open Science Data to Research Life in Space
Article
1 week ago
5 min read Old Missions, New Discoveries: NASA’s Data Archives Accelerate Science
Article
1 week ago
3 min read NASA Open Data Turns Science Into Art
Article
1 month ago
Keep Exploring Discover More Topics From NASA
Missions
Humans in Space
Climate Change
Solar System
View the full article
-
By NASA
Illustration of the main asteroid belt, orbiting the Sun between Mars and JupiterNASA NASA’s powerful James Webb Space Telescope includes asteroids on its list of objects studied and secrets revealed.
A team led by researchers at the Massachusetts Institute of Technology (MIT) in Cambridge repurposed Webb’s observations of a distant star to reveal a population of small asteroids — smaller than astronomers had ever detected orbiting the Sun in the main asteroid belt between Mars and Jupiter.
The 138 new asteroids range from the size of a bus to the size of a stadium — a size range in the main belt that has not been observable with ground-based telescopes. Knowing how many main belt asteroids are in different size ranges can tell us something about how asteroids have been changed over time by collisions. That process is related to how some of them have escaped the main belt over the solar system’s history, and even how meteorites end up on Earth.
“We now understand more about how small objects in the asteroid belt are formed and how many there could be,” said Tom Greene, an astrophysicist at NASA’s Ames Research Center in California’s Silicon Valley and co-author on the paper presenting the results. “Asteroids this size likely formed from collisions between larger ones in the main belt and are likely to drift towards the vicinity of Earth and the Sun.”
Insights from this research could inform the work of the Asteroid Threat Assessment Project at Ames. ATAP works across disciplines to support NASA’s Planetary Defense Coordination Office by studying what would happen in the case of an Earth impact and modeling the associated risks.
“It’s exciting that Webb’s capabilities can be used to glean insights into asteroids,” said Jessie Dotson, an astrophysicist at Ames and member of ATAP. “Understanding the sizes, numbers, and evolutionary history of smaller main belt asteroids provides important background about the near-Earth asteroids we study for planetary defense.”
Illustration of the James Webb Space TelescopeNASA The team that made the asteroid detections, led by research scientist Artem Burdanov and professor of planetary science Julien de Wit, both of MIT, developed a method to analyze existing Webb images for the presence of asteroids that may have been inadvertently “caught on film” as they passed in front of the telescope. Using the new image processing technique, they studied more than 10,000 images of the star TRAPPIST-1, originally taken to search for atmospheres around planets orbiting the star, in the search for life beyond Earth.
Asteroids shine more brightly in infrared light, the wavelength Webb is tuned to detect, than in visible light, helping reveal the population of main belt asteroids that had gone unnoticed until now. NASA will also take advantage of that infrared glow with an upcoming mission, the Near-Earth Object (NEO) Surveyor. NEO Surveyor is the first space telescope specifically designed to hunt for near-Earth asteroids and comets that may be potential hazards to Earth.
The paper presenting this research, “Detections of decameter main-belt asteroids with JWST,” was published Dec. 9 in Nature.
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
For news media:
Members of the news media interested in covering this topic should reach out to the NASA Ames newsroom.
View the full article
-
By USH
Where do asteroids get all those craters? Countless small circular craters, plus almost always a few that look like massive killers. Even more confusing is that these craters are at a perfect 90º angle, as if an electric arc had run across the surface.
According to ThunderboltsProject, the Electric Universe (EU) model, the scars observed on asteroids are caused by electric arcs which cut surface depressions, scoop out material, accelerate it into space, then leave behind clean-cut geological relief.
This theory is supported by Electric Discharge Machining (EDM), a process we use every day to shape materials with electric arcs, producing similar clean-cut effects.
This brings us to the following hypothesis: Could it be that, instead of craters on asteroids being formed solely by natural space phenomena, that all these craters at a perfect 90º angle with clean-cut geological relief are the result of asteroid mining originated by alien races who use advanced electric arc/laser technology by extracting raw minerals they urgently need for use on their planet or for in-space manufacturing?
Asteroids vary greatly in composition, ranging from those rich in volatile substances to those composed of metals like gold, silver, platinum, cobalt, and palladium, alongside more common elements such as iron and nickel. This makes them potential treasure troves of valuable resources.
For us as Earthlings, asteroid mining is a technology in its earliest stages and requires significant advances in robotic technology before asteroid mining becomes a reality, however, if more advanced civilizations exist elsewhere in the universe, it's quite plausible that some of them have already turned to asteroid mining long ago.
Could their efforts be leaving behind the very craters on asteroids we observe today?
View the full article
-
-
Check out these Videos
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.