Definitions for near-earth
near-earth

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1. near-earth

   A near-Earth object (NEO) is any small Solar System body whose orbit brings it into proximity with Earth. By convention, a Solar System body is a NEO if its closest approach to the Sun (perihelion) is less than 1.3 astronomical units (AU). If a NEO's orbit crosses the Earth's orbit, and the object is larger than 140 meters (460 ft) across, it is considered a potentially hazardous object (PHO). Most known PHOs and NEOs are asteroids, but a small fraction are comets.There are over 30,503 known near-Earth asteroids (NEAs) and over a hundred known short-period near-Earth comets (NECs). A number of solar-orbiting meteoroids were large enough to be tracked in space before striking the Earth. It is now widely accepted that collisions in the past have had a significant role in shaping the geological and biological history of the Earth. Asteroids as small as 20 metres (66 ft) in diameter can cause significant damage to the local environment and human populations. Larger asteroids penetrate the atmosphere to the surface of the Earth, producing craters if they impact a continent or tsunamis if they impact the sea. Interest in NEOs has increased since the 1980s because of greater awareness of this potential danger. Asteroid impact avoidance by deflection is possible in principle, and methods of mitigation are being researched.Two scales, the simple Torino scale and the more complex Palermo scale, rate the risk presented by an identified NEO based on the probability of it impacting the Earth and on how severe the consequences of such an impact would be. Some NEOs have had temporarily positive Torino or Palermo scale ratings after their discovery. Since 1998, the United States, the European Union, and other nations are scanning the sky for NEOs in an effort called Spaceguard. The initial US Congress mandate to NASA to catalog at least 90% of NEOs that are at least 1 kilometre (3,300 ft) in diameter, sufficient to cause a global catastrophe, was met by 2011. In later years, the survey effort was expanded to include smaller objects which have the potential for large-scale, though not global, damage. NEOs have low surface gravity, and many have Earth-like orbits that make them easy targets for spacecraft. As of January 2019, five near-Earth comets and five near-Earth asteroids have been visited by spacecraft. A small sample of one NEO was returned to Earth in 2010, and similar missions are in progress. Preliminary plans for commercial asteroid mining have been drafted by private startup companies, either through the use of robots or even by sending private commercial astronauts to act as space miners.

How to pronounce near-earth?

1. Alex

   US English

   David

   US English

   Mark

   US English

   Daniel

   British

   Libby

   British

   Mia

   British

   Karen

   Australian

   Hayley

   Australian

   Natasha

   Australian

   Veena

   Indian

   Priya

   Indian

   Neerja

   Indian

   Zira

   US English

   Oliver

   British

   Wendy

   British

   Fred

   US English

   Tessa

   South African

How to say near-earth in sign language?

Numerology

1. Chaldean Numerology

   The numerical value of near-earth in Chaldean Numerology is: 3

2. Pythagorean Numerology

   The numerical value of near-earth in Pythagorean Numerology is: 9

Examples of near-earth in a Sentence

1. Patrick Michel:

   We have the very exciting chance that two space missions visited two primitive Near-Earth asteroids at about the same times, which allows us to discover two new small worlds, what really fascinated us when we saw the first images, is the amazing similarity of the two objects, before more detailed observations made differences emerge. This is really fascinating because these asteroids were chosen totally independently from one mission to the other.

2. Bill Gray:

   Jon pointed out that JPL's Horizons system showed that the DSCOVR spacecraft's trajectory did not go particularly close to the moon. It would be a little strange if the second stage went right past the moon, while DSCOVR was in another part of the sky. There's always some separation, but this was suspiciously large, analysis led by NASA's Jet Propulsion Laboratory's Center for Near-Earth Object Studies indicates the object expected to impact the far side of the Moon March 4 is likely the Chinese Chang' e 5-T1 booster launched in 2014.

3. Davide Farnocchia:

   Scout quickly ruled out 2023 BU as an impactor, but despite the very few observations, it was nonetheless able to predict that the asteroid would make an extraordinarily close approach with Earth, in fact, this is one of the closest approaches by a known near-Earth object ever recorded.

References

1. ^ Wikipedia
   https://en.wikipedia.org/wiki/Near-Earth