BAN #233: A new comet to watch, watching your language

6 July 2020   Issue #233

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

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Pic o’ the Letter

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

There’s a comet up in the early morning skies called C/2020 F3 (NEOWISE). It’s on a highly elongated orbit (it came from deep space) with a period of roughly 2.5 million years, so once it heads back out, it’s gone. It reached perihelion (closest point to the Sun) in early July, and will be closest to Earth around 23 July at a distance of a little over 100 million kilometers.

It’s currently not quite bright enough to see naked eye, but some predictions are that it might be bright enough to see when it gets closer to Earth. It’s always hard to say with comets. Over the next few weeks it’ll be low to the west after sunset, but rising a bit higher every day. At perigee (closest to Earth) it’ll be just below the bowl of the Big Dipper, so pretty easy to spot. You can get a finder chart and more info on CometWatch.

Some people already have a pretty good view of it though, like Ivan Vagner, a Russian cosmonaut on the International Space Station. He posted this great shot of it:

[Credit: Ivan Vagner/Roscosmos]

Oof. Nice. If you look at the shot full-res it looks like it has zillions of stars in the background, but they’re not. At first I thought they were “hot pixels”, which are pixels in the camera’s detector that are more sensitive than average, so they appear brighter. That happens in space with cameras; cosmic rays (subatomic particles zipping around) can damage electronic detectors over time. When I was working on Hubble we had to monitor that pretty often with our camera, because you don’t want to think you’ve discovered a supernova or something when it’s actually due to a far more local event. But after a discussion on Twitter I think it’s likely these actually are low energy cosmic rays themselves hitting the detector and activating those pixels.

Anyway, I hope y’all get a chance to see it. I’ll have my binocs out for it over the next couple of weeks (sadly, the Moon becomes a problem starting around the 26th or so after it’s half full). I haven’t seen a comet for a while, and this one may be a good one!

Social justice

If we don’t do our part, who will?

My friend Chris Pirillo retweeted something from Twitter Engineering that got me thinking.

[Credit: Twitter Engineering]

I am all for reshaping our language to do things like this; I’ve written about using “crewed” instead of “manned” for spaceflight. I’m glad Twitter is a) doing this and 2) being public about it. The more we talk about things like this the more normalized they become.

As someone who enjoys thinking about language and words, I was surprised when I got to the last one: “dummy”. It’s obviously a derogatory term for someone who isn’t smart, but their use of it here, I thought, has a different meaning: In this case (“placeholder”) it’s a temporary stand-in for something that will be replaced or defined better later. Clearly, that’s not related to being not smart, I figured; it came from the term dummy meaning a mannequin or puppet, a replacement for or model of a human.

But then I started wondering: Why was “dummy” used for “mannequin” anyway?

Since I’m ever curious about such things, I searched on “etymology dummy” and got a surprise. The usage of it as a mannequin came about from the term “dumb” meaning “unable to speak”. Someone who was dumb was derogatorily called a dummy.

Holy yikes! The path of the term became clear. So I was right in that it came from mannequin, but that in turn came from an ableist origin! So Twitter is right, and good on them. Now if only they’d actually ban Nazis…

Anyway, I learned something! It doesn’t come up often for me IRL, but I imagine it does for a lot of people, so hopefully the term “dummy” can be replaced in these contexts.

It’s always interesting to look up word origins (see here and my followup tweet). They tend to be surprising, which I love, and finding this stuff out can lead to not just fun trivia but also a better understanding of just how thoughtless people can be, and how it can be mainstreamed over decades and centuries to the point where no one really thinks about the use anymore.

I’ve said before that empathy can save us. And in cases like this, it’s a pretty small effort to make a pretty big change, and more importantly it’s the right thing to do.

[Addendum: Ironically, in the article in that last link above about empathy, I use the work “dumb”. Hmph. Well, that stops here and now.]

Blog Jam

What I’ve recently written on the blog, ICYMI        

[Artwork depicting an active galaxy, with a supermassive black hole in its center. From Wednesday’s post. Credit: DESY, Science Communication Lab]

Monday 39 June, 2020: Merging black holes blast out light… but not for the reason you'd think

Tuesday 30 June, 2020: New study: The asteroid killed the dinosaurs, but volcanoes made things… better?

Wednesday 1 July, 2020: In the distant Universe a supermassive black hole eats a sun *a day*

Thursday 2 July, 2020: Did Betelgeuse fade due to supersized sunspots?

Friday 3 July, 2020: Pulsars, black holes, spacetime, and the search for the center of the solar system

Et alia

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