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quarter-water t1_j3k6glj wrote

Reply to comment by AFineDayForScience in TIL Pluto hasn't completed an orbit around the sun since its discovery. Pluto's orbit takes about 248 years, and Pluto was discovered in 1930. by irbinator

>Mercury: 47.87 km/s (107,082 miles per hour), or a period of about 87.97 days

Fun fact: A year on Mercury is 88 Earth days, but because of rotational resonance, a day is 175 Earth days if you were standing on Mercury.

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Seraph062 t1_j3kn3ic wrote

> a day (one complete rotation) is 175 Earth days lol

A day isn't really a complete rotation.
A complete sidereal rotation (i.e. the time it takes to complete a single 360 degree rotation) on Mercury is about 59 Earth days.
However 'a day' is generally measured with respect to the parent star, and since Mercury is moving around the sun that represents a moving target, and it takes 175 Earth days for the sun complete one cycle in the sky (e.g. local noon -> local noon).

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quarter-water t1_j3lm3a4 wrote

You're right, I added the parts in parenthesis after but it's not totally correct. The 175 day is how long someone on Mercury would feel like "a day" ie from noon to noon.

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mic_Ch t1_j3llxm5 wrote

So when people say "I wish it could be Christmas everyday" we should send them to Mercury, as a bonus they get every other holiday thrown in for free!

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Orodruin666 t1_j3mn8lj wrote

Would make visiting the inlaws truly last an eternity

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afanofBTBAM t1_j3lxbk2 wrote

>(one rotation around the sun)

IIRC, this is called a revolution, and the term rotation is reserved for the celestial body itself spinning upon its axis.

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quarter-water t1_j3lxo46 wrote

Yeah, it was late.. my post is full of holes lol I've edited jt now

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