Here the discovery images from last night 🙂 pic.twitter.com/nPEnf8jzPK
— Kacper Wierzchoś (@WierzchosKacper) September 19, 2020
The Mt. Lemmon Survey discovered a 4-meter asteroid 2020 SW when it was 0.017 AU (6.616 LD) away on 2020 09 18. It will make a close approach of 0.07 lunar distances on 202 09 24. To aid in understanding how close this is let’s make a mental scale model of the Earth.
![A scale model of the Earth. using a ball with a diameter of 29.21 cm (11.5 inches) [this happens to be the same as the length of a football ball(American)] to represent the Earth.
-- A CM would be 436.2204724 KM, an inch would be 1108 KM. -- The International Space Station would be 9.2 mm away. -- the Asteroid 2020 SW to Flyby ~0.5 yards -- Geosynchronous orbit would be 820.4 mm, 0.8204 m, or 0.8972 yards -- Light-second would be 6872.5 mm, 6.8725 m, or 7.5159 yards -- a Lunar distance would be 8666.1 mm, 8.6661 m, or 9.4773 yards.](https://theasteroidnews.com/7767AUT/wp-content/uploads/2020/09/The_Blue_Marble-a-449x1024.jpg?189db0&189db0)
The 2020 SW flybe will be ~0.5 yards from our scale model of the Earth. As of 2020-09-21 this flybe will be ranks 24th.
| Object | Close-Approach (CA) Date | CA Distance Nominal (LD | au) | H (mag) | Estimated Diameter |
| 2020QG | 2020-Aug-16 | 0.02 | 6.23e-5 | 29.9 | 2.8 m- 6.3 m |
| 2011CQ1 | 2011-Feb-04 | 0.03 | 7.92e-5 | 32.1 | 1.0 m- 2.3 m |
| 2019UN13 | 2019-Oct-31 | 0.03 | 8.43e-5 | 32 | 1.1 m- 2.4 m |
| 2008TS26 | 2008-Oct-09 | 0.03 | 8.44e-5 | 33.2 | 0.61 m – 1.4 m |
| 2004FU162 | 2004-Mar-31 | 0.03 | 8.63e-5 | 28.7 | 4.8 m- 11 m |
| 2020CD3 | 2019-Apr-04 | 0.03 | 8.77e-5 | 31.7 | 1.2 m-2.8 m |
| 2020JJ | 2020-May-04 | 0.03 | 8.96e-5 | 30 | 2.7 m – 6.0 m |
| 2018UA | 2018-Oct-19 | 0.04 | 9.14e-5 | 30.2 | 2.4 m- 5.4 m |
| 2016DY30 | 2016-Feb-25 | 0.04 | 9.56e-5 | 30.5 | 2.1 m- 4.7 m |
| 2019AS5 | 2019-Jan-08 | 0.04 | 0.00010 | 32.3 | 0.92 m- 2.1 m |
| 2020CW | 2020-Feb-01 | 0.04 | 0.00011 | 32.5 | 0.83 m- 1.9 m |
| 2017GM | 2017-Apr-04 | 0.04 | 0.00011 | 29.9 | 2.8 m- 6.2 m |
| 2017UJ2 | 2017-Oct-20 | 0.05 | 0.00012 | 30.9 | 1.8 m – 3.9 m |
| 2011MD | 2011-Jun-27 | 0.05 | 0.00012 | 28 | 6.7 m – 15 m |
| 2014LY21 | 2014-Jun-03 | 0.05 | 0.00013 | 29.1 | 4.0 m – 9.0 m |
| 2009VA | 2009-Nov-06 | 0.05 | 0.00014 | 28.6 | 5.1 m – 11 m |
| 2012 KT42 | 2012-May-29 | 0.05 | 0.00014 | 29 | 4.2 m – 9.4 m |
| 2017EA | 2017-Mar-02 | 0.05 | 0.00014 | 30.8 | 1.8 m- 4.1 m |
| 2019EH1 | 2019-Mar-01 | 0.06 | 0.00016 | 30.1 | 2.5 m- 5.7 m |
| 2016RN41 | 2016-Sep-11 | 0.06 | 0.00016 | 31 | 1.7 m – 3.7 m |
| 2015SK7 | 2015-Sep-22 | 0.07 | 0.00018 | 28.9 | 4.4 m- 9.9 m |
| 2016AH164 | 2016-Jan-12 | 0.07 | 0.00018 | 29.7 | 3.1 m- 6.8 m |
| 2013YB | 2013-Dec-23 | 0.07 | 0.00018 | 31.5 | 1.3 m- 3.0 m |
| 2020 SW | 2020-Sep-24 | 0.07 | 0.00019 | 28.9 | 4.4 m – 9.9 m |
| 2017WE30 | 2017-Nov-26 | 0.08 | 0.00020 | 31.9 | 1.1 m- 2.5 m |
Background(as of 2020-08-21)
- Object: 2020 SW
- Orbit Type: NEO (Apollo)
- Approximate Diameter: 4.4 m – 9.9 m [14.4357 feet to 32.4803 feet] (Absolute H= 28.9)
- On the Sentry Risk Table: Yes [archive] [5 Number of Potential Impacts 2093-2118 ]
- Torino Scale (maximum): 0
- Palermo Scale (maximum): -9.07
- Palermo Scale (cumulative): -8.92
- Diameter: 0.006 km
- Mass: 2.3e+5 kg
- Energy:4.5e-3 Mt
- for more information on risk, pages read Understanding Risk Pages by Jon Giorgini
- On the NEODyS CLOMON2 risk page: Yes [archive] [12 Number of Potential Impacts 2086-2113 ]
- Torino Scale (maximum): 0
- Palermo Scale (maximum): -8.99
- Palermo Scale (cumulative): –8.37
- Energy: 7.60e-10 Mt
- Listed on Near-Earth Object Human Space Flight Accessible Targets Study (NHATS): Yes [archive]
- Listed on the Goldstone Asteroid Radar Schedule: No
- Listed on the Arecibo Asteroid Radar Schedule: No
- Radar Observations: none
- Discovery observation was made: 2020 09 18.31827 [7:38:18.52] by Mt. Lemmon Survey (MPC Code G96).
- Last Observation(publish) was made: 2020 09 21.21525 [05:09:57.60] by Mt. Lemmon Station (MPC Code I52)
- The number of Optical Observations(published):28
- Oppositions: 1
- Observation arc: 3 day
- The number of Observatories Reporting (Published) Observations: 7
- Observatories Reporting (Published) Observations(MPC Code):
- (F51) Pan-STARRS 1, Haleakala, Hawaii, USA.
- (G34) Oberfrauendorf, Germany.
- (G96) Mt. Lemmon Survey, Arizona, USA.
- (I52) Steward Observatory, Mt. Lemmon Station, Arizona, USA.
- (J04) ESA Optical Ground Station, Tenerife, Canary Islands, Spain
- (L01) Višnjan Observatory, Tičan,Croatia.
- (V06) Catalina Sky Survey-Kuiper, Arizona, USA.
- Perihelion Distance: 0.822 AU
- Aphelion Distance: 1.208 AU
- Earth MOID: 0.000507161 AU ( 0.197 Lunar Distance) 11.895 Earth radii
- Close-Approach to Earth: Date and Time(TDB): 2020-Sep-24 11:18
- Time Uncertainty: ± 00:24 ( 23.5965877046877 minutes)
- Minimum Distance: 0.000187106487150934 (AU), 0.073 (LD) 4.389 Earth radii, 17,392.635 miles, 27,990.732 KM
- Nominal Distance(best fit): 0.000187915859624005 (AU), 0.073 (LD), 4.408 Earth radii, 17,467.87 miles, 28,111.812 KM
- Maximum Distance: 0.000188726786694858 (AU) 0.073 (LD), 4.427 Earth radii, 17,543.251 miles, 28,233.125 KM
- Was, it Be Visible to the Unaided Eye: NO
Sources
- Asteroid (NEO) 2020 SW Information (TheSkyLive.com)
- ESA 2020SW
- JPL Small-Body Database Browser (2020 SW)
- MPC Database Search — 2020 SW
- MPEC 2020-S83 : 2020 SW
- Palermo Technical Impact Hazard Scale
- Introduction to Sentry: Earth Impact Monitoring
- Sentry: Earth Impact Monitoring
- Torino Scale
Other Useful Links
- Asteroid Hazards: The View from Space(MPC)
- Don’t fear apocalyptic asteroids: you’re safer than you think
- Frequently Asked Questions For Impact Risk Assessment
- NEO Search & Follow-Up
- Palermo Technical Impact Hazard Scale
- Quantifying the risk posed by potential Earth impacts Steven R. Chesley (JPL), Paul W. Chodas (JPL), Andrea Milani (Univ. Pisa), Giovanni B. Valsecchi Icarus 159, 423-432 (2002) ( PDF )
The Asteroid 2020 NK1 Has Been Removed From Sentry: Earth Impact Monitoring