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RE: MystiFACT-or-FICTION challenge #2 - Our Solar System, Our Home
Great post! However, in this article under Mercury you said, "Its year is longer than its day." Are you referring to Mercury's "sidereal day" or "solar day"? I assumed solar, and posted my response with what I felt were actually 2 mistakes in this post.
It seems like we have an expert on the topic. I would have never spotted something like this ^_^
Lol, I'm no expert! I actually erroneously read the sentence as, "Its day is longer than its year" the first time through. I looked it into it further (to prove it wrong) and discovered that depending on the definition of "day" one chooses it could actually be true! The hint at the bottom made it obvious the error was with classifying Pluto as a planet, but I was curious and figured I would bring it up anyways.
Hi! Sadly, that isn't the mistake. In Astronomy, if you refer to a day or year, it is most of the time Solar and not Sidereal. Thank you for your response nevertheless, and it is still valid for your hard work, unless you would like to submit another one. Best of luck!
I found this site which says: "Based on data obtained by these radar measurements, Mercury is now known to be in 3:2 orbital resonance with the Sun. This means that the planet completes three rotations on its axis for every two orbits it makes around the Sun. At it’s current rotational velocity – 3.026 m/s, or 10.892 km/h (6.77 mph) – it takes Mercury 58.646 days to complete a single rotation on its axis. While this might lead some to conclude that a single day on Mercury is about 58 Earth days – thus making the length of a day and year correspond to the same 3:2 ratio – this would be inaccurate. Due to its rapid orbital velocity and slow sidereal rotation, a Solar Day on Mercury (the time it takes for the Sun to return to the same place in the sky) is actually 176 days."
https://www.universetoday.com/47834/length-of-day-on-mercury/
Interesting... I think with Astronomy especially, everything we know has a certain level of uncertainty. It is widely known that a day on Mercury is 88 Earth days so in my opinion, that is the "most accepted" theory out there.
Hey no problem, we can agree to disagree. Good luck with your future posts/challenges!