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by lamacase 1235 days ago
A golf ball is around 4cm, and an arm's length is around 70cm. To be the same apparent size, it would have to maintain that same ratio. The atmosphere is like 50-100km thick (highest weather balloon flight was >50km) so you would have to be seeing it at a further distance than that.

So your asteroid would have to be at least several kilometers across. That approaching dino-killer size. You're definitely misremembering some part of this.
1 comments
wrycoder 1235 days ago
It's not impossible. How closely were we tracking 3 km objects in 1983?
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zardo 1234 days ago
The US and USSR were looking very closely for much smaller objects leaving and entering the atmosphere.
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wrycoder 1234 days ago
True, but are they finding them - especially the ones on the sun side of our orbit? Remember, this one was found by an amateur. Now, NASA is claiming authority for it.
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