BAN #265: Grant Imahara, Testing Ariane 6, Minutia Men interview

26 October 2020   Issue #265

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

Subscribers are tested, primed, and ready for ignition.

Do gooding

Doing some good

In July 2020 the world dimmed a bit: Grant Imahara passed away. He was a beloved figure in geek culture, involved much more deeply than being a Mythbuster. He built robots, worked on TV shows and movies, and was an all-around nice guy with a huge circle of friends.

23 October was his 50th birthday. To honor him, and his drive to be curious and generous, his mother has started a foundation: The Grant Imahara STEAM Foundation’s mission “is to inspire emerging talent and empower underserved youth in Science, Technology, Engineering, Art, and Math education.”

They made a video all about it:

This is a terrific way to honor a terrific guy. You can donate and/or volunteer, and maybe help the world make up a little bit for the huge deficit of his loss.

[I took this photo of Grant backstage at W00tstock, a sortof geekapalooza that used to go on at San Diego Comic Con every year, and then went on the road to a bunch of different cities. Pretty sure the head belonged to Adam Savage, and this is my favorite shot of Grant, made even more so because I don’t remember the context at all. Credit: Phil Plait]

Blog Jam

What I’ve recently written on the blog, ICYMI

[ OSIRIS-REx is a little too good at its job. From Saturday’s post. Credit: NASA/Goddard/University of Arizona ]

Monday 19 October, 2020: Astronomers see the Milky Way eating one of its own

Tuesday 20 October, 2020: No, an asteroid is not likely to hit Earth the day before the election

Wednesday 21 October, 2020: A dying star’s magnetic racing stripes

Thursday 22 October, 2020: BOOP! NASA spacecraft OSIRIS-REx pokes an asteroid and collects the debris

Friday 23 October, 2020: When we look out at alien worlds, are those alien worlds looking back?

BONUS: Saturday 24 October, 2020: UPDATE: The Bennu asteroid sample collection was successful! Almost too succesful

Space news

Space is big. That’s why we call it “space”

[Artwork showing Ariane 6, the next generation in the venerable ESA rocket series. Credit: ESA]

The European Space Agency is currently building the Ariane 6, the next generation in its venerable and very successful Ariane rocket line. The hope is that it will cost less than the Ariane 5 and launch more often.

It’s a powerful rocket, capable of sending 5 tons to geosynchronous orbit (36,000 km above Earth’s equator, where an orbit takes 24 hours to complete, so a satellite appears to “hover” over one spot on the Earth), over 11 tons to a low orbit that can transfer to geosynch (so, a satellite plus small booster to send it up to geosynch) and 22 tons to low-Earth orbit.

It will have a liquid fuel core booster, with either two or four strap-on solid rocket boosters, called P120Cs. They just tested one of these SRBs on the ground in what’s called a hot fire, igniting it and letting it run for the full launch-capable 130 seconds. The video is… well, it’s something.

Yowza! Each P120C generates 4.5 million Newtons of thrust. Thrust is a force, and that’s equivalent to about a million pounds of thrust. That’s a lot. The single most powerful liquid fuel rocket motor was the F-1, five of which were on the first stage of the Saturn V rocket that took astronauts to the Moon, and each of those generates about 1.5 million pounds of thrust. So these P120Cs are pretty mighty.

And, in fact, all the engines for Ariane 6 have been tested and are now qualified for flight.

It’s too bad the Ariane 6 is an expendable rocket — launch it once and throw it away. I’ll note the SpaceX Falcon Heavy can launch more to orbit than the Ariane 6 — 64 tons to low orbit, and 27 to GTO. The cost per launch is about the same for both rockets ($90M for the FH and $95 for A6), but the FH is reusable.

I really hope and wish the national space agencies would focus on reusable rockets more. On the other hand there may not be a point, with commercial companies working hard on them. It’s an odd time for space agencies to be developing rockets, honestly. I’m curious to see how this will shake out. SpaceX has been vigorously moving forward with the Starship rocket, which will dwarf existing capabilities if it works, and will cost far less (the aspirational goal is $2M per flight, which is incredibly low, but even 10 times this cost is dirt cheap for the capability).

The apocryphal phrase “may you live in interesting times” is jokingly thought of as a curse. I’m not so sure that’s always true.

Upcoming Appearances/Shameless Self-Promotion


Where I’ll be doing things you can watch and listen to or read about

I was interviewed by Rick Kaempfer and Dave Stern on the Minutia Men podcast about, well, minutia. Well, actually, we talk mostly about critical thinking: phrases, asteroid impacts, Uranus, COVID-19, and more.


I had a lot of fun — I really enjoy doing more light-hearted podcasts, with a lot of joking around — but I also got myself twisted up taking about anti-vaxxers. I brought up measles as a highly infectious disease, and oh, a good minute after I brought it up and was talking about it, I realized I couldn’t remember if it was caused by a virus or a bacterium. The part of my brain controlling my talking was fine, but this other part of the brain started to panic, and I wound up having to dance around saying whether it was one or the other. At some point I also brain froze and said it was caused by varicella, but that’s actually the chicken pox virus. Measles is caused by — get this — the measles virus. Duh. Well, that’s the old name; the official one is now Measles morbilivirus.


Oh: I also messed up the origin of the phrase “Spanish flu”, somewhat, too. The intro paragraphs to this disease on Wikipedia explain what’s what.


Anyway, it’s weird how, especially in interviews or talks or whatever, you can launch into a topic and then realize some words in that you’ve forgotten the important bits on the topic. I think pretty much anyone who’s done these sorts of things has faced that situation. So I apologize for my brain. I take full responsibility but it’s not my fault.
Anyway, enjoy the interview and if you like it follow the Minutia Men on Twitter.

Et alia

You can email me at thebadastronomer@gmail.com (though replies can take a while), and all my social media outlets are gathered together at about.me. Also, if you don’t already, please subscribe to this newsletter! And feel free to tell a friend or nine, too. Thanks!