The Ominous Reason Phobos Has Lines on It

Mars’s moon, Phobos, is striped with grooves all across its surface. But if one theory about where they came from is true, does that mean this moon might be on its way out?

Hosted by: Hank Green (he/him)
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[nuldorvamoysenor]

And, if the Doom games are to be believed, gravitational stress caused by the opening of multiples portals to hell could be one of the main contributors to such grooves.

[elguinolo]

This is the Phobos commuter tram line, which brings Martian workers from the Phobos Housing projects to the Phobos Water Well and back twice a sol. It was abandoned in 34, 566 ME when the well ran dry, and the workers relocated to the Tharsis salt mines, but the tracks remained to this day.

[RtB]

The hardest leap for many people to make is the idea that not everything - in deed hardly anything - that we see in the structure of the solar system is "historic" and happened a long time ago. Like continental drift...it's happening right now. We're just lacking the time scale to see it.

[nickbourgade]

"Phobos suffered from multiple traumatic events in the past."

Me too, Phobos...Me too...

[NewMessage]

Multiple traumatic events in my past explain my phobias, too.

[emreyurtseven]

As soon as Hank posed the question I thought "hmm they look like stretch marks, maybe Mars is causing it" and boom there it was later in the video. I've never felt more accomplished in my life, which is sad... :D

[Andysalive]

The canals-on-Mars guy would have had a field day with these tracks.

[SathReacts]

Is it 'INTERNATIONAL SELL ME A CALENDAR DAY'? SciShow, SciShow Space, PBS Eons, Journey to the Microcosmos... Yall having an internal side bet about which page will sell more?

[kennethwood]

Aha! I see that you added the Saturnian moon Hyperion to your new calendar. That's great.
Hyperion, like a giant slush ball in space with an impact crater more than half it's size, is mysteriously & spectacularly frozen in mid-splash!
Interestingly enough, on the surface of Mars, Phobos & Deimos appear to travel in opposite directions; because one travels faster than planet's the rotation and the other slower.

[Kevin_Street]

Stretch marks caused by tidal forces sounds about right. Somewhat like an egg, Phobos can take a hammer blow to the end without losing structural integrity - but the constant stretching and squeezing is too much.

[lesleyghostdragon]

Hank Green, you are just the most adorable "widdle" nerd, with your Phobos, flanked by a "widdle Mars", merry month of May calendar page...The context is cuteness!😘

[tkc]

If Phobos is that small, wouldn't any impact strong enough to make a crater that big be MUCH stronger than Phobos' weak gravity? I would figure almost everything would be blasted away. And in the presented scenario, if the gravity really is that weak, the debris shouldn't gouge very strongly into the surface. After all, it isn't enough to just be traveling across something; you need downward force, too. Shouldn't the gouging would be proportionate to the normal force? And very weak gravity means a very weak normal force. And for those boulders to not be flung into Mars' gravity, they'd have to be moving pretty slow. So even if their speed is sapped slowly, it shouldn't take them long to come to a stop. If I had to pick, I would say the second hypothesis is more likely.

[craigmooring]

Phobos was also the name of one of the four horses that drew the War Chariot of Ares. Who names his son after his horse, and how did it affect the fraternal relationship? "Dad liked me best; he named you after his horse!"

[mirthenary]

I almost named my two oldest cats Phobos and Deimos, sadly Midnight (Deimos) is no longer with us 😢 He was 13, RIP Lil buddy 2/14/09 - 4/3/22

[zachb]

Imagine how cool it would've looked if we got a Shoemaker Levvy view of that collision with Phobos. Also... woo boy... the history of our solar system and its heavenly bodies is anything if not disquieting. Next time an asteroid gets pulled into Earth's orbit I can only hope good ol' Luna face-tanks it for the team.

[AlecMuller]

I'm looking forward to data from JAXA's MMX probe! It will be great to know more about Phobos's composition. Seems like a prime location for a gas station & tether counterweight.

[Kualinar]

Remember that Phobos orbital period is about 23 hour long, or about 1 hour less than Mars day.

[MatataMcCleskey]

30 to 50 million years until Mars pulls it's moon apart.
But I wanna see it now!

[HalkerVeil]

3:40 Has nobody noticed taht Phobos and Deimos look like puzzle pieces that belong together?

[paulkinzer]

I love the bouncing rocks graphics!

And the first time I saw those grooves in an image, my mind jumped to tidal disruption. Maybe I chose the wrong career, and should have picked planetology over childcare. Nah, kids are a kick!