Mercury: Crash Course Astronomy #13

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Mercury is the closest planet to the sun. It has no atmosphere and is, as such, covered in craters. It’s also incredibly hot but, surprisingly, has water ice hiding beneath its surface.

Table of Contents
Closest Planet to the Sun 0:03
Rotation Locked to its 2 to 3 Orbit Ratio 3:10
Deep Crater Water Ice 8:39

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Mercury relief in Olomouc: [credit: Michal Maňas]
Mercury: Phil Plait
Mercury in color: [credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington]
Earth Based View of Mercury: [credit: Catalina Observatory]
Caloris Basin: [credit: NASA, Johns Hopkins Univ. APL, Arizona State U., CIW]
[credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington]
Mercury’s core: [credit: Nicolle Rager Fuller, National Science Foundation]
Mercury’s Ice Lockers: [credit: NASA Goddard Space Flight Center/Massachusetts Institute of Technology/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington]
Mercury’s Tail: [credit: NASA]


theCountniggula says:

What keeps ice from sublimation and simply gassing all the ice away from the planets over millions of years in that cold of an environment?

Mayank Dahiya says:

Solid Ice On Mercury, a planet like Mercury. This Facts gives me Goose Bumps. Biggest Surprise Of My Astronomy Learning Career…

Crustation fish says:

do you think Mercury could ever be habitable?

KnightCraft 130 says:

that puns tho

YouTubeIsGay says:

I wonder if life will have enough time to form on Mercury as the solar system heats up and the ice has time to turn into liquid water

Wyatt Pauline says:

thank for the info

João Felipe says:

So basically mercury is the remaining core of an older planet?
I mean, it's like a leftover.

Fevernova 77i says:

It took me a while to understand from 5:08 to 5:30. I'll break it up for the one's who are facing the same problem as I did.
1) At Aphelion, Mercury's angular rotational speed is faster than it's angular orbital speed, so the Sun moves rapidly to the west side in the sky.
2) Four days before Perihelion, the angular orbital velocity of Mercury is equal to the angular rotational velocity, so the Sun appears to stop in the sky.
3) While now at Perihelion, the angular orbital velocity of Mercury is more than the angular rotational velocity, so the Sun appears to move eastwards.
4) Now as the Mercury is pulled away from the Sun i.e. it leaves it Perihelion position, again it moves westwards as the angular rotational velocity dominates over the angular orbital velocity.

Mike Collins says:

This video told me a lot about Mercury that I didn't know, but it didn't answer the question I had – about the anomaly of Mercury's orbit that had to be explained through Relativity. I have looked in other places, where the anomaly seems to be its precession – but I don't think relativity is needed to explain that. I'm guessing that when precession is taken into account, the orbit is still not exactly what it is expected to be. The answer must be out there somewhere – but the Internet is a big place!

Jonny Provost says:

Nature has a large imagination huh? Bet it has a good personality too

siddhant gupta says:

How can we see Mercury in the night if it's always in front of the face of the Earth when Earth faces the sun?

duhast43 says:

"of course in the harsh heat, that water just goes fsstttttt" LOL
made my day

SteamKing2160 says:

The result on Mercury's trip around the sun is a double sunrise. Anyway, there is a Caloris Impact on Mercury that is 800 miles wide, the culprit was probably a planetesimal, a lump of primordial matter. Also, the Mercurian core is 70% iron making Mercury the densest planet in the solar system and that Mercurian core is as big as our moon. I think 4.5 billion years ago, a planet blasted the mantle off Mercury while its debris headed towards Venus. Mercury's magnetic field is just 1% of Earth's. Mercury has a temperature range up to 1,100 degrees Fahrenheit but only when it's near the sun.

Leo Hunter says:

Hey are you Mercury? Because I find you pretty hot… and cool 😉

Robert Andersson says:

Thank you very much for making this video, Phil Plait, Though Café and the rest of CrashCourse Astronomy! It was fascinating to learn about Mercury, surely one of the weirdest planets in our solar system.

I have a question for you: you said that Mercury stated out as a very big planet and than got small do to a collision with something. A few episodes back, you talked about the moon and how it was formed by a collision between Earth and the planet Theia. Is it possible that Mercury was Theia all along? Is the Moon a child of Earth and Mercury? What do the space geologists say?

Ah4b says:

Are the higher velocities of impacts on Mercury also due to the fact that closer to the sun, asteroids orbiting the sun are near their perihel, i.e. where their velocity peaks during orbit?

York says:

kerbal space program

Gee Money says:

also very informative he talks way too fast for me to absorb any of the information

Atri Mazumder says:

new glasses

NotPickyButStrict says:

the intro killed me xD

grak182 says:

I could just listen to you talk about the stars all day.

Evan PB says:

Actually, a lot of scientists believe that the water ice is formed from frozen gasses.

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