2017 SG33 (also written 2017 SG33) is a near-Earth object, meaning that it has an orbit which brings it into proximity with Earth. It is an Amor asteroid, meaning that its orbit does not cross Earth's orbit, but its perihelion is close to, but greater than, the aphelion of Earth. It was first observed on 25 September 2017, when the asteroid was less than 1 AU from Earth[1] and had a solar elongation of 169°.[5]

2017 SG33
Discovery[1]
Discovered byPan-STARRS
Discovery siteHaleakala Obs.
Discovery date25 September 2017
(first observation only)
Designations
2017 SG33
NEOAmor[1][2]
Orbital characteristics[2]
Epoch 25 September 2017 (JD 2458021.5)
Uncertainty parameter 9[2] · E[1]
Observation arc0.83 days[3]
Aphelion3.03±0.26 AU
Perihelion1.13±0.20 AU
2.08±0.18 AU
Eccentricity0.46±0.14
3.00±0.39 years
19.7°±4.3°
0° 19m 42.24s / day
Inclination5.14°±0.69°
189.0°±0.9°
116°±27°
Earth MOID0.144 AU (56 LD)
Physical characteristics
Mean diameter

This asteroid is a lost asteroid.[6] It has a very short observation arc of 0.83 days and has not been seen since 2017, so it has an orbit that is only roughly calculated. Also, there are variations in the absolute magnitude cataloged by various organizations, leading to variations in the estimated size of the asteroid (Sentry list H 23.9 implies 55 m[3] vs MPC H 23.3 implies 75 m[1]). These variations are in addition to the uncertainty in the size estimate caused by the uncertainty in the albedo.[7]

This asteroid is in the Risk List and the Priority List of the European Space Agency (ESA) - Space Situational Awareness (SSA).[4] The asteroid is also in the Sentry List of the Jet Propulsion Laboratory (JPL) - Center for Near Earth Object Studies (CNEOS).[8] According to the Sentry List, of the possible close encounters with Earth in the foreseeable future, an encounter on September 8, 2051 has the highest Palermo Technical Impact Hazard Scale value.[3]

According to the Near Earth Objects Dynamic Site (NEODyS), of the possible close encounters with Earth in the foreseeable future, an encounter on 1 August 2023 is the most likely.[9] This encounter has a minimum possible distance of zero, meaning that an impact onto Earth was thought possible.

See also edit

References edit

  1. ^ a b c d e f "2017 SG33". Minor Planet Center. Retrieved 11 September 2020.
  2. ^ a b c d "JPL Small-Body Database Browser: (2017 SG33)" (2017-09-26 last obs.). Jet Propulsion Laboratory. Retrieved 11 September 2020.
  3. ^ a b c d e "Sentry: Earth Impact Monitoring - Object Details 2017 SG33". Jet Propulsion Laboratory. Retrieved 6 September 2020.
  4. ^ a b c "ESA space situational awareness 2017SG33". European Space Agency. Retrieved 6 September 2020.
  5. ^ "JPL HORIZONS Web-Interface (2017 SG33)". Jet Propulsion Laboratory. Retrieved 6 September 2020.
  6. ^ "NEODyS-2 Risk List". SpaceDys. Retrieved 6 September 2020.
  7. ^ "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 11 September 2020.
  8. ^ "Sentry: Earth Impact Monitoring - Impact Risk Data". Jet Propulsion Laboratory. Retrieved 6 September 2020.
  9. ^ "NEODyS-2 - Near Earth Objects - Dynamic Site - 2017SG33 - Close Approaches". SpaceDys. Retrieved 6 September 2020.

External links edit