BAN #325: Curiosity from Mars orbit, How to watch this week’s lunar eclipse

24 May 2021   Issue #325

[The planetary nebula M 2-9, winds from a dying star. Credit: NASA / ESA / Hubble Legacy Archive / Judy Schmidt]

Subscribers have a curiosity (and generosity) that can be seen from orbit.

Pic o’ the Letter

A cool or lovely or mind-bending astronomical image/video with a short description so you can grok it

ICYMI late last week NASA’s Mars Reconnaissance Orbiter HiRISE camera folks released this image showing an outcrop of rock on the Martian surface taken from space that oh yeah also happens TO SHOW THE CURIOSITY ROVER SITTING ON IT.

[The Curiosity rover seen from orbit. Credit: NASA/JPL/UArizona]

That’s nuts. You can see the rover body clearly and even kinda sorta see the wheels.  Curiosity was examining rocks near the top edge of a small cliff 6 meters high. The rover itself is about three meters long.

I strongly urge you to follow HiRISE on Twitter, because the images they post pretty much every day are jaw dropping… though some are more jaw-dropping than others.

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Blog Jam

What I’ve recently written on the blog, ICYMI

[The X-ray diffraction pattern of icosahedrite, a bizarre form of crystal newly found in a mineral sample of sand fused into glass by the very first atomic bomb test. From Tuesday’s article. Credit: Asimow et al.]

Monday 17 May, 2021: Dark matter might heat exoplanets enough to make them glow

Tuesday 18 May, 2021: A nuclear test creates a forbidden crystal. This is the fivefold way.

Wednesday 19 May, 2021: Just how many stars *is* Albireo, and is one of them a black hole?

Thursday 20 May, 2021: Wait: Do black holes *really* swarm in the core of globular cluster NGC 6397?

Friday 21 May, 2021: Methuselah’s Star is not older than the Universe after all. But it’s still pretty frakking old.

What’s Up?

Look up! There’s stuff to see in the sky!

[A photo I took of a lunar eclipse in September 2015, when it was still partial. Credit: Phil Plait]

There’s a lunar eclipse this week! It’s not at a great time for US viewers unless you’re either a very late night person, a very early riser, or you live in Hawaii, in which case the timing is great.

The event begins on Wednesday May 26th early in the morning. Technically the eclipse begins at 08:47 UTC (01:47 Pacific time), but that’s when the outer dimmer shadow of the Earth (called the penumbra) first touches the Moon. The darker part (the umbra) makes contact at 09:45 UTC (02:45 PT), and the Moon is fully covered by 11:11 UTC (04:11 PT) and totality only lasts 16 minutes — the Moon is cutting a very shallow chord across Earth’s shadow this time, so the eclipse is short.

Hopefully the Moon will turn a blood red during totality, as light from the Sun filtered through Earth’s air can be distinctly red. It’s a sight to behold.

Also, because this happens so late the Sun will rise and the Moon will set for a lot of the US before totality ends. I’ll barely catch it here in Colorado — totality ends minutes before the Moon sets (just as the Sun rises).

Hawai’ians get the best view in the US, since the eclipse starts at 10:47 p.m. on the evening of the 25th and ends at 03:50. Folks in eastern Australia also can see the whole thing. This map shows who can see it.

Here’s a video I shot of the September 2015 lunar eclipse as the moon was rising; the color is mostly due to the eclipse (look how dark it is on the left) but partly due to junk in the air. But a couple of planes flew right across it as I shot this, so that was cool.

If you want details on this eclipse Sky and Telescope has you covered, as does The Planetary Society. I also have a bit to say about lunar eclipses in general in an episode of Crash Course Astronomy:

(The lunar eclipse stuff starts at 06:43).

The Virtual Telescope Project 2.0 will also be doing a live viewing.

I’ll note this happens when the Moon is near perigee, it’s closest approach to Earth in its elliptical orbit; it’ll be about 357,400 kilometers away (on average it’s more like 384,000). So it’ll be bigger than usual, but only by about 7%. You probably wouldn’t notice. Beware of anyone breathlessly claiming it’s a “supermoon” — in general it hardly matters. The difference isn’t a lot and unless you’re pretty familiar with observing the Moon it’s hard to see any difference. It does affect tides more than usual (which depend strongly on the Moon’s distance) but that’s about it.

Still, a lunar eclipse can be quite beautiful, so if you’re up give it a look! And take photos if you can, too. It’s not easy to get good ones, but when you do it’s worth the effort.

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