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Something Twice the Size of Earth Slammed into Uranus and Knocked It Over (2018)

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Re: Something Twice the Size of Earth Slammed into Uranus and Knocked It Over (2018)

#6
post #3

So Uranus is "tilted on its side relative to its fellow planets, by about 98 degrees." Why is that not an 82-degree rotation?

Axial tilt is sometimes defined such that 0° is when the orbital and rotational axes align, including direction of rotation; Venus has a tilt of 177° by this standard, because of its retrograde rotation compared to the majority of the planets.

Re: Something Twice the Size of Earth Slammed into Uranus and Knocked It Over (2018)

#7
The simulation suggests it could have happened that way. That doesn't translate well into that headline. (Given the domain name, a person might hope for better.)

Impact hypotheses are a popular type of explanation. Some may survive actual exposure to evidence, and eventually become theories. This is quite an old idea (as is the idea that the Moon impacted the Earth); maybe one day it'll pan out.

Until then, it'd be great to see fewer hypotheses in 'Science News' headlines ... and more evidence.

Re: Something Twice the Size of Earth Slammed into Uranus and Knocked It Over (2018)

#8
post #3

So Uranus is "tilted on its side relative to its fellow planets, by about 98 degrees." Why is that not an 82-degree rotation?

Possibly because that would explain its rotation being the reverse of the other planets(except Venus). If it started rotating the same way as the other planets and were rotated 82 degrees, it would still be rotating in the same direction as the other planets, where as by rotating 98 degrees, the rotation is reversed.

Re: Something Twice the Size of Earth Slammed into Uranus and Knocked It Over (2018)

#9

I've been alive for many, many decades. I wish I could say I've matured past Uranus double entendres, but I haven't.

I will freely admit that I had the same reaction to the headline. Ow! I think I'd remember something like that.

#forever12

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