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AFineDayForScience t1_j3k141p wrote

This made me curious about the orbital speed of each planet.

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

Venus: 35.02 km/s (78,337 miles per hour), or a period of about 224.7 days

Earth: 29.78 km/s (66,615 miles per hour), or a period of about 365.256365 days

Mars: 24.077 km/s (53,853 miles per hour), or a period of about 686.93 days

Jupiter: 13.07 km/s (29,236 miles per hour), or a period of about 11.86 years

Saturn: 9.69 km/s (21,675 miles per hour), or a period of about 29.42 years

Uranus: 6.81 km/s (15,233 miles per hour), or a period of about 83.75 years

Neptune: 5.43 km/s (12,146 miles per hour), or a period of about 163.72 years

Pluto: 4.74 km/s (10,603 miles per hour), or a period of about 247.92 years

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quarter-water t1_j3k6glj wrote

>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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gsohyeah t1_j3k7s2q wrote

What about degrees of revolution per time, per mass of the planet, per average distance from the sun? I feel like they'll all be the same number or are there more variables?

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