RIP Oliver Sacks

Today I Learned:
1) Oliver Sacks is dead. This is the kind of thing that pushed me into Bioengineering in the first place.

Thanks to Menghsa Gong for bringing this to my attention.

2) Phobos is a really weird little moon. It’s incredibly close to its parent planet (9,000 km, compared to more than 30,000 km for our moon). It’s tiny — only about 14 miles across. It’s also getting closer to Mars, and in about 50 megayears it will cross the Roche Limit, which is the point where tidal forces of its parent will rip it apart into rubble.

Deimos, for the record, is even smaller (about half the radius), but has an orbit closer to that of the moon. I’m not sure if it’s getting closer or father away.

Thanks to Bungie’s Ride Along: Mars video.

3) One more Mars fact from that video — at least some of Mars’s dunes have visible rivulets on them that are probably from water. Through a process I don’t entirely understand, water trapped in the dunes sometimes melts and lightly erupts from the dunes, leaving little channels that we can see.