BAN #179: ALMA countdown, Artistic goat, Arctic melting

30 December 2019   Issue #179

[Saturn image credit: NASA / JPL / Space Science Institute / Gordan Ugarkovic]

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Blast from the Past

A quick link to an old post or article because it’s relevant, or came up in conversation, or just because it deserves a second look.

Last week on the blog I posted an article about the Top Ten observations made by the ALMA Observatory in 2019. It’s a countdown, so the videos are going up every day. Happily, the folks at NRAO, who did the animations, have a blog they’re updating as the videos go up so you can find them all in one place.

For your enjoyment, and as an example, here’s Number 5: Binary stars born in a cosmic pretzel:

I wrote and did the voice-overs for the videos, and I’m proud of how this turned out. It was a lot of work, and a lot of fun. I hope you like ‘em, too.

Personal Stuff

Yeah, but not too personal

So I was scrolling through Instagram recently, looking at everyone’s photos of their dinner, their friends, and sunsets they just saw (I’m guilty, too, I admit), and I get a notification that someone has tagged me in something they posted. That doesn’t happen often, so I take a look…

… and I see this. I mean, WOW.

[Artwork by Kat Perkins]

That drawing is by Kat Perkins, and I love it.

For those of you who don’t know, I live on a few acres in rural Colorado, and a few years ago my wife and I decided to go all in on this stereotype and get outdoor animals. After watching a bunch of videos of adorable baby goats, we decided to get some of our own.

My daughter named one Clayton Forrester, after MST3K (though I still think of him as one of my favorite scientists from a movie that shaped my own childhood). Clayton is the ringleader of the pack of four we have, and arguably the most photogenic. I was out earlier in 2019 to feed the herd, and took this photo of him contentedly munching on some hay:

[Credit: Phil Plait]

Seriously. In her IG post about it, Kat said she did her drawing of Clayton “just for practice funsies”, and her quick sketch is about a billion times better than I could ever do.

So I contacted her and told her how much I loved it, and I wanted to buy it. We made an arrangement, and now it’s mine! I just got it in the mail so I haven’t framed it yet, but rest assured it’ll be hanging somewhere in my house. The photo I took of it above doesn’t do it justice. It’s really great.

And hey, Kat takes commissions to draw pets and people! Clearly, she’s good, so if you’re looking for a lovely way to immortalize some fauna in your life, drop her a line. Tell her Clayton the goat sent you.

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Is it hot in here, or is it just anthropogenic global warming?

Climate change is real, y’all

Here’s a year-end story I wish I didn’t have to write.

Every year, the ice floating in the Arctic waxes and wanes with the season. It usually reaches its maximum extent in March after a winter of cooling, then starts to shrink with summer, reaching its minimum extent in September. It’s been measured using satellites since 1978; the area of the Arctic is divided into area bins, and the extent is defined as percentage of bins that are 15% or more covered in ice.

To the surprise of absolutely no one, this year’s minimum is a near-record low, essentially tying 2007 and 2016 for the second lowest extent since the satellite observations began. The area was 4.15 million square kilometers.

[Credit: Joshua Stevens, using data from the National Snow and Ice Data Center]

In the image above, the yellow line shows the median September ice extent measured from 1981 – 2010 (median is a little different than average; I describe the math in a blog post). As you can see, this September was far, far less.

Extent is a measure of area, but the volume is dropping too. This is a bit different, because (obviously) it includes depth of the ice, but another reason is that old ice tends to be thicker, having had time to build up lots of volume. Newer frozen ice, though, tends to be thinner. This is a double whammy: Not only is the amount of ice dropping, but old ice is melting too, so what new ice we get every year is thinner and melts more easily in the summer.

This video shows that in dramatic fashion: The change in the volume of sea ice every year compared to 1979:

Yikes. There’s a reason this is called the Arctic Ice Death Spiral.

This reason for all this is of course global warming. The Arctic is heating up about twice as fast as the rest of the planet, and in fact this is largely due to that sea ice. As the Earth warms, the ice melts. But there’s an amplification effect from sea ice: It’s white. That means it’s reflective, so it reflects the vast majority of sunlight that hits it, which in turn means it doesn’t absorb much of the Sun’s heat.

But when it melts, what’s left? Sea water. And that’s dark, which means it absorbs sunlight, and therefore heat, much more efficiently than ice. So the Arctic warms much faster than most other places on Earth.

If, like me, this fills you with dread — as it damn well should — then what can we do?

The answer to that is complicated, but I can winnow it down to one simple action. Seriously.


If we keep electing Republicans, this death spiral will continue. Most other countries are doing their share, but our representatives in government not only deny there’s a problem, they call it a hoax, making it even harder to do anything about it.

I have a lot of problems with the GOP, but have no doubt this is one of if not the very biggest. That’s why, no matter who wins the primary next year and who runs on the Democratic side in my state elections, I will vote blue. If we had something other than a two-party system that might be different, but for now this is the reality we face.


Blog Jam

What I’ve recently written on the blog, ICYMI

[Betelgeuse, which won’t be exploding any time soon. From Tuesday’s article. Credit: ALMA (ESO/NAOJ/NRAO)/E. O’Gorman/P. Kervella ]

Monday 23 December, 2019: The top 5 astronomy stories for 2019

Tuesday 24 December, 2019: Don’t panic! Betelgeuse is (almost certainly) not about to explode

Wednesday 25 December, 2019: A galactic Christmas tree lit up by magnetic fields and interloping stars

Thursday 26 December, 2019: A little red and green for the holiday: RCW 120, a huge shell of gas from a runaway star

Friday 27 December, 2019: Countdown: Top Ten ALMA Observations of 2019

Et alia

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