Talk:2019 OK

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What was it's ground-track as it passed earth?

Just wondering where this thing was (above what location on earth) at it's closest approach. And where might it have hit (along what arc) if it had impacted.

Also, is there enough known about it's orbit to guess the next close fly-by? It no doubt has come close to earth in the past, and will again in the future. — Preceding unsigned comment added by 198.2.107.38 (talk) 02:34, 29 July 2019 (UTC)[reply]

I don't know, but here is an animation: [1]. Cheers, Rowan Forest (talk) 02:50, 29 July 2019 (UTC)[reply]

As the two orbits do NOT intersect (come within 1.5 Earth radii), no impact was possible. Closest Earth approach was 0.00047 AU (70,000 km) and the asteroid was moving roughly 24.5 km/s (88,000 km/h) relative to Earth, so in theory it would still have taken the asteroid another 1 hour to reach Earth. — Preceding unsigned comment added by Kheider (talk • contribs) 17:58, 31 July 2019 (UTC)[reply]

Chelabinsk deleted

I deleted the comparison with Chelabinsk meteor because it seems like synthesis using an old reference that does not actually compare it to the 2019 OK asteroid. Besides, Chelabinsk was about 20 m, while 2019 OK (and Tunguska) size estimates are nearly identical (50 to 190 m). Rowan Forest (talk) 02:49, 29 July 2019 (UTC)[reply]

Yes, the "30 times Hiroshima" claim was clearly bullshit (and completely unsourced) for this object, yet it remained in the article for several days. 188.150.69.142 (talk) 12:00, 6 August 2019 (UTC)[reply]

The comparison with Chelabinsk was for "smaller asteroids" with an absolute magnitude H of around 26. 2019 OK had and absolute magnitude of 23.3 and therefore 2019 OK should be at least 50 meters in diameter. One of the sources does compare it to over 30 times Hiroshima, which is accurate enough if the object is 50 meters in diameter AND of a low density. -- Kheider (talk) 15:53, 6 August 2019 (UTC)[reply]

That sounds highly unlikely. The low density (carboniferous) asteroids are usually very dark. If it was such an asteroid, it would have been much larger than 57m, which is considered the minimum size. At this size it would have been bright. It would have been made out of a bright material. Even 57 m is still nearly three times the size of the Chelyabinsk asteroid. It also passed at a faster pace compared with the Chelyabinsk Asteroid. Basically, even the lowest possible realistic value would be something like eight to ten times the energy of the Chelyabinsk asteroid. Multi-Megaton range. The most likely size and mass is if it was considered a 80-100 m stony object, which would have had the energy of many, many megatons of energy. 80 m diameter at 2.6 g/cm3 and 24 km/s speed, gives about 49 Mt of TNT energy. If it was the largest estimated diameter, but still somehow stony, this would mean it could have been 130 m dia, 2.6 g/cm3 and 24 km/s, which results in 209 megatons. Probably less likely. Basically, the "30 times Hiroshima" is not a calculated value, just something some Australian astronomer said, without calculating anything. 109.57.146.135 (talk) 18:13, 17 May 2020 (UTC)[reply]

Etymology

Why is it called OK? Mateussf (talk) 02:21, 1 August 2019 (UTC)[reply]

Mateussf: I think Provisional designation in astronomy#New-style provisional designation explains it. It is quite the fortuitous title, so perhaps an explanation in the article is warranted? Eman 235/talk 20:56, 2 August 2019 (UTC)[reply]

I think the way it is know is good. Thanks! (By the way, it's impressive that the only 10 objects were discovered between 16 and 24 July. The article does a good job explaining it is because of the full moon). Mateussf (talk) 17:58, 3 August 2019 (UTC)[reply]

Orbit

I suggest we add when will the asteroid flyby Earth again. Rowan Forest (talk) 15:14, 4 August 2019 (UTC)[reply]

It really does not look like 2019 OK will make any more notable approaches until 28 July 2116 when it will pass by at about 0.03 AU (4,500,000 km; 2,800,000 mi). Given the asteroids sub-kilometer size even the 2116 pass is not really notable. That date is aleady mentioned in the article. -- Kheider (talk) 16:38, 4 August 2019 (UTC)[reply]

Thanks. Rowan Forest (talk) 22:48, 4 August 2019 (UTC)[reply]