BAN #193: Moon occults Mars tonight!, Noisemaking women

17 February 2020   Issue #193

[Spiral Galaxy M81 image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona]

Subscribers unblock the stars.

What’s Up?

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

This is VERY exciting: The Moon will occult Mars tonight/tomorrow morning!

An occultation is when one astronomical object passes in front of another — like an eclipse — and having planets occulted by the Moon is relatively rare. So if you can, take this chance to see it!

It’s not visible everywhere, but this event favors North America. The timing of it depends on your longitude — for one thing there are time zones, but for another the Moon is close enough to the Earth that different longitudes see it from slightly different angles, which changes the moment it passes in front of Mars due to parallax. Your latitude is important too, which changes which part of the Moon’s bright limb Mars will disappear behind.

It happens before sunrise Tuesday, and some folks will see the Moon block Mars, some will see the planet reappear a little over an hour later, and some can see both. For me, it happens around 04:40 local time.

The good folks at Sky and Telescope magazine have a ton of info about this event, including timings for major cities, and links to where you can find your own times. They recommend getting a copy of the software Stellarium which you can then set to your location to get more info. I recommend this as well; it’s a pretty good piece of software and it’s free! If you want to see what your sky looks like and what’s going on, it’s excellent. As always, I like Sky Safari as well, and the $3 version will almost certainly handle everything you need from a planetarium app. I use it all the time.

[Credit: Sky Safari]

Speaking of which, when I looked up the occultation in Sky Safari, it showed me that this happens right between the Lagoon and Trifid nebulae! That’s cool. I think the Moon may be too bright to see them, but a wide-angle eyepiece in a low-power telescope may give you a glimpse.

The weather here has been all over the place, but I’m hoping to get up a few hours early to take a look at this. I’ve seen a few occultations, but not one with Mars, so I’m excited!

And if you see it and get photos, post them to social media! I’d love to see them.

Clear skies to all y’all!

I recommend

Something I think you’ll like

A few years ago I tweeted in support of a magazine called Kazoo that encourages girls to study STEM fields:

That was in 2016, and it was fully funded! That’s great news. And it gets better: These same folks have put together a book, called “Noisemakers: 25 Women Who Raised Their Voices and Changed the World”. It’s a graphic collection, short stories like a comic book featuring different authors and artist covering important women who made a difference.

They sent me a copy, and it’s really, really great. The women they highlight were scientists, inventors, artists, poets, and more. It’s really wonderful. Of course, I was taken with the one about Caroline Herschel:

[Credit: Kazoo Magazine]

That’s just one page. I also really loved the art for fossil hunter Mary Anning.

[Credit: Kazoo Magazine]

More than just stories, there is engagement as well, with questions asking the reader, for example to “count all the things you have in common with” the person, listing things such as “I Like to explore”, “I like to write”, and so on. It draws the reader in, gives them a point of contact with this person (who, in some cases, lived centuries ago), making them real.

Of course, it would be easy to say that all girls should read this, but when I was a lad I was not exposed to too many female role models; we read “A Wrinkle in Time” but even then (as a boy nerd) I identified more with Charles Wallace than Meg.

And that’s why I think it’s just as important that young boys read this book as well. We do a disservice to both boys and girls to pigeon-hole them into rigid gender roles for themselves. Let them see that people of any gender, or any sex, are all equal, and all able to do the things we dream of doing. Explore space, explore humanity, craft artwork… these are part of being human, and not necessarily relegated to one kind of person or another.

My advice: Get this book and give it to a young one you know. Or better yet, donate it to a school library. That will help maximize its potential.

Blog Jam

What I’ve recently written on the blog, ICYMI

[An actual image of the disk of Betelgeuse shows part of it looks normal and part is much dimmer. Credit: ESO/M. Montargès et al.]

Monday 10 February, 2020: First light for the exoplanet hunter mission CHEOPS goes tetrahedral

Tuesday 11 February, 2020: Star clusters can disrupt planetary systems, tossing planets into black holes

Wednesday 12 February, 2020: Astronomers find a star dive-bombing our galaxy's supermassive black hole

Thursday 13 February, 2020: Exoplanet smashup: The very weird dust disk around BD +20 307

Friday 14 February, 2020: Betelgeuse’s shenanigans just got weirder: Only * part * of it is dimming

Et alia

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