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Near-Earth asteroid

From Encyc

The first asteroids to be discovered were all found in the gap between Planet Mars and Planet Jupiter, but, as the number of asteroids grew, some, the near-Earth asteroids, crossed Planet Earth's orbit. They are sometimes called near-Earth objects, or NEOs

Eros, discovered in 1898, is the first asteroid to be classified as a near-Earth asteroid.[1][2]

Some notable near-Earth asteroids
name discovered size period notes
433 Eros 1898 16.84 kilometres (10.46 mi) 643 days
  • The first asteroid to be classified as a near-Earth asteroid.[1][2]
  • First asteroid to be visited by a space probe.[1][2]
99942 Apophis 2004 340 metres (1,120 ft) 0.9 years
  • When Apophis was first detected it was believed there was a possibility it might strike Planet Earth, in 2029.[3][4]
  • A space probe named Osirix-Apex is being prepared to rendezvous with Apophis during its 2029 close approach.[5]
101955 Bennu
3753 Cruithne
65803 Didymos
3200 Phaethon 1983 5.1 kilometres (3.2 mi) 524 days

References

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  1. ↑ 1.0 1.1 1.2 "Asteroid Eros". Space Reference. Archived from the original on 2021-01-20. Retrieved 2026-06-09. Eros is a large asteroid whose orbit approaches the orbit of Earth but does not cross it. NASA JPL has classified Eros as a 'Near Earth Asteroid' due to its orbit's proximity to Earth, but it is not considered potentially hazardous because computer simulations have not indicated any imminent likelihood of future collision.
  2. ↑ 2.0 2.1 2.2 "433 Eros". NASA Science. 2017-11-18. Archived from the original on 2026-03-28. Retrieved 2026-06-09. Eros is famous as the first asteroid to be orbited by a spacecraft, and the first asteroid to have a spacecraft land on it. But Eros was important to astronomers as far back as 1898 when it became the first near-Earth asteroid (NEA) to be discovered.
  3. ↑ "Apophis Facts". NASA Science. 2025-03-28. Archived from the original on 2026-06-05. Retrieved 2026-06-09. Asteroid Apophis will safely pass close to Earth on April 13, 2029. This will be the closest approach to Earth by an asteroid of this size that scientists have known about in advance.
  4. ↑ "Apophis". NASA Science. 2020-06-18. Archived from the original on 2023-09-29. Retrieved 2026-06-09. Near-Earth asteroid Apophis is a potentially hazardous asteroid that will safely pass close to Earth on April 13, 2029. It will come about 20,000 miles (32,000 kilometers) from our planet’s surface — closer than the distance of many satellites in geosynchronous orbit (about 22,236 miles, or 36,000 kilometers, in altitude).
  5. ↑ Jamie Adkins (2023-10-31). "OSIRIS-APEX". NASA Science. Archived from the original on 2026-05-25. Retrieved 2026-06-09. OSIRIS-APEX will allow scientists on Earth to observe these changes. Additionally, the OSIRIS-APEX spacecraft will dip toward the surface of Apophis ­– a “stony” asteroid made of silicate (or rocky) material and a mixture of metallic nickel and iron ­-- and fire its engines to kick up loose rocks and dust. This maneuver will give scientists a peek at the composition of material just below the asteroid’s surface. soft hyphen character in |quote= at position 150 (help)
  6. ↑ Anton Petrov (2019-02-08). "One of the Weirdest Rocks in the Solar System - 3200 Phaethon" (video). What da math. Retrieved 2026-06-07 – via YouTube. ...in this video, we will talk about 3200 Phaethon - an unusual blue asteroid that's not really an asteroid nor a comet. A rock comet...
  7. ↑ Anton Petrov (2022-10-28). "This Already Strange Asteroid Just Got Weirder, 3200 Phaethon Discovery" (video). What da math. Retrieved 2026-06-07 – via YouTube.
  8. ↑ Deborah Byrd (2025-12-12). "Mysterious 3200 Phaethon is the Geminids' parent object". EarthSky. Retrieved 2026-06-07.
  9. ↑ "Geminids". NASA Science. 2017-11-20. Archived from the original on 2023-09-30. Retrieved 2026-06-07. Asteroid 3200 Phaethon takes 1.4 years to orbit the Sun once. It is possible that Phaethon is a "dead comet" or a new kind of object being discussed by astronomers called a "rock comet."
  10. ↑ "Meteor Showers Ranked". Eastern Sierra Observatory. 2019-08-12. Retrieved 2026-06-07. Meteor showers rain down from the cosmos throughout the year. These showers occur when Earth passes through a debris field in its orbit. Most of the debris we come in contact with is "dust" shed by comets traveling through the solar system, but meteors can range in size from as tiny as microns to as large as 1 meter. Anything larger than that is considered an asteroid or comet. Meteors typically enter our atmosphere traveling at speeds of 25,000 mph to 160,000 mph.
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