Jump to content

Hyperbolic asteroid

From Wikipedia, the free encyclopedia
(Redirected from A/2019 G4)

A hyperbolic asteroid is any sort of asteroid or non-cometary astronomical object observed to have an orbit not bound to the Sun and will have an orbital eccentricity greater than 1 when near perihelion.[1] Unlike hyperbolic comets, they have not been seen out-gassing light elements, and therefore have no cometary coma. Most of these objects will only be weakly hyperbolic and will not be of interstellar origin.

Orbit explanation

[edit]

The planets and most satellites of the solar system revolve in an almost circular motion – called an elliptical orbit – around the Sun or their parent planet, so their orbital eccentricity is generally much closer to 0 than to 1. In mathematics, by definition, an eccentricity (e) of 1 characterizes a parabola, and e > 1, a hyperbola. Some comets are on parabolic and hyperbolic orbits. This means that these hyperbolic asteroids all have an orbital eccentricity greater than 1.

Known hyperbolic asteroids

[edit]

So far most hyperbolic asteroids discovered have later displayed cometary behavior by either outgassing or demonstrating motion based on solar radiation pressure. Hyperbolic asteroids are orbital objects with an orbit not bound to the Sun while near perihelion.[2] ʻOumuamua had the motion of a comet but was never seen outgassing and thus it is listed as a hyperbolic asteroid by the JPL Small-Body Database.[3]

Perturbation

[edit]

Asteroids can become ejected or in a highly eccentric orbit around the Sun by being ejected by planets like Jupiter. Just because an orbit solution looks unbound at an epoch when the object is near perihelion (closest approach to the Sun) does not mean the orbit will be unbound when beyond the planets.[10]

See also

[edit]

References

[edit]
  1. ^ "JPL Solar System Dynamics".
  2. ^ "Hyperbolic Asteroids | Space Reference". www.spacereference.org. Retrieved 12 November 2019.
  3. ^ "JPL Small-Body Database Search Engine: orbital class Hyperbolic Asteroid (HYA)". Jet Propulsion Laboratory Solar System Dynamics. Retrieved 4 March 2018.
  4. ^ Web Archive from 5 March 2018 for A/2017 U7
  5. ^ Web Archive from 5 March 2018 for A/2018 C2
  6. ^ Web Archive from 28 March 2018 for A/2018 F4
  7. ^ "A/2019 O3". JPL Small-Body Database Browser. Retrieved 28 December 2019.
  8. ^ "C/2019 G4". JPL Small-Body Database Browser. Retrieved 11 August 2022.
  9. ^ Croswell, Ken (2017). "Astronomers race to learn from first interstellar asteroid ever seen". Nature News. doi:10.1038/nature.2017.22925.
  10. ^ de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl; Aarseth, Sverre J. (6 February 2018). "Where the Solar system meets the solar neighbourhood: patterns in the distribution of radiants of observed hyperbolic minor bodies". Monthly Notices of the Royal Astronomical Society Letters. 476 (1): L1–L5. arXiv:1802.00778. Bibcode:2018MNRAS.476L...1D. doi:10.1093/mnrasl/sly019.
[edit]