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There's a lot of hoopla online about asteroid 2021 LD6's close approach to Earth. Will be close enough and large enough to be seen with the naked eye?

PS: More on the object: MPC or JPL

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    $\begingroup$ Welcome to astronomy SE. Would be great if you could specify the "hoopla"... $\endgroup$
    – B--rian
    Jun 29, 2021 at 8:10
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    $\begingroup$ By "hoopla" I mean "media attention." Sounds like it's overblown, like many things. $\endgroup$
    – Rob Adams
    Jun 29, 2021 at 22:01
  • $\begingroup$ I understood that you are talking about media attention, but the point is that I do not find much media attention on the web, that's why I would appreciate a link or two. $\endgroup$
    – B--rian
    Jun 30, 2021 at 8:56
  • $\begingroup$ @uhoh Have you heard about it in non-nerd media? $\endgroup$
    – B--rian
    Jun 30, 2021 at 8:57
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    $\begingroup$ @B--rian There was a Jun 14 tweet prematurely noting a possible impact 58 years later. I'd rather not boost it. $\endgroup$
    – Mike G
    Jun 30, 2021 at 13:42

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No, at its brightest in June 2021, 2021 LD6 [MPC, JPL] was apparent magnitude 20-21, well beyond the reach of most amateur telescopes. At absolute magnitude H=27.3, it's not very large, and at 10.5 times the lunar distance, it wasn't very close.

Gideon van Buitenen keeps a list of near-Earth objects (NEOs) which will appear brighter than magnitude 14 sometime in the next 12 months. Naked-eye NEOs are quite rare.

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    $\begingroup$ @RobAdams For reference, in excellent conditions with good eyesight you might be able to see objects with apparent magnitudes of ~8 . Each point on the scale translates to a 2.5 change in brightness meaning that at app. mag. 21 the object is ~159,000 times less bright than the dimmest objects you can possibly see. so it's not even close. $\endgroup$
    – eps
    Jun 29, 2021 at 17:42
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    $\begingroup$ @eps Magnitude 6 is a more realistic naked-eye limit. $\endgroup$
    – Mike G
    Jun 29, 2021 at 18:14
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    $\begingroup$ yep, for sure -- most people don't have perfect eyesight observing the sky on a moonless night in the middle of absolute nowhere. I first wrote 6-8 but just decided to go with the best case scenario for simplicity. Even 6 is probably not possible if you are in the limits of a big city. $\endgroup$
    – eps
    Jun 29, 2021 at 20:23

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