[Note: Every week I hold a live video chat on Google+ where I answer questions from readers. I call it Q&BA, and when I get a question that stands alone, I'll make it its own video. ]

Every now and again, I hear this urban legend that pound for pound, the human body is actually hotter (or has more energy) than the Sun. I got this question in a recent Q&BA video chat session, so I tackled it. The answer is pretty interesting, and depends on how you ask the question!

I actually wrote about this legend on the blog a while back, and I show all the math. I really like this question, since it has a straightforward answer that makes it seem wrong, but then if you look at it more carefully the answer is a little trickier. And even in the video and that other post, it’s not really a complete answer; if you read the comments on the post you’ll see people arguing over it.

That’s really the best kind of question: the ones that keep on going! There’s always more stuff to figure out.

Visit the Q&BA Archive to see more videos like this one!

[Note: Every week I hold a live video chat on Google+ where I answer questions from readers. I call it Q&BA, and when I get a question that stands alone, I'll make it its own video. ]

A lot of people, it seems, have morbid thoughts about space. Why else would I get asked this so much: "What would happen to the human body exposed to the vacuum and cold of space?"

Of course, this sort of thing is depicted in scifi movies a lot, and people are curious about it. And even though the movies always get it wrong — you don’t explode, or freeze instantly — it does make folks wonder about it. And while the reality isn’t maybe as gooey as in the movies, it’s still pretty nasty.

I wrote about this in my review of the movie "Mission to Mars", as well as answering a question many years ago from a reader. And even though it’s an icky thing to think about, it does give me a chance to talk about heat transfer, which is pretty, um, cool.

A few years ago, I started doing a weekly video question-and-answer session I called "Q & BA". It was a series of short videos that were a lot of fun to make. Unfortunately, the overhead got to be too high — it took all day to edit them! — and I had to stop.

But now, Google+ has changed that: Hangouts On Air is a feature that allows me to go on camera and broadcast a live video chat session to an unlimited audience. I take questions via Twitter and G+, and it’s a lot of fun. It lasts about an hour, and I put the whole session on YouTube. But some of the answers stand alone, and it’s easy to extract them out, package ‘em up, and post ‘em by themselves.

So I’m very pleased to announce I’m starting the series again! The first Q&BA is a great question: "What’s the best way to get kids into science and skepticism?" — what better way to get the series going again? Enjoy.

I’ll be posting more of these, maybe even one per day as time allows. If you like them, please give them a thumbs-up on YouTube, and drop by the Q&BA Hangout when I do them live! I announce them on Twitter and G+, so follow me there and stay up-to-date. Also, I have an archive with links to all the videos. Thanks!

I hate to have to do this, but Q & BA is going on hiatus for a while. My schedule is out of control, with many projects coming to a head, and I simply don’t have the time to devote to these videos. It’s killing me, but the decision had to be made.

I’m not cancelling it or stopping altogether; I’m just putting it on hold for a few months until things calm down. I’m hoping to restart it this summer if I can.

I apologize for having to do this, but… well, I’ll just say that some of the projects I’m working on will be very cool, and well worth the effort. You’ll see.

Viewing options:

Watch it on YouTube.

Download it directly from LibSyn.

Download the audio only version from LibSyn.

NOTE: If you are already a subscriber through iTunes, you may be getting both the video and the audio-only versions in your feed. This is because both versions were in one feed until last week. If you want to get only one or want to download both separately, then unsubscribe first and then click on the link(s) below.

Subscribe to AUDIO ONLY VERSION via iTunes.

Subscribe to VIDEO VERSION via iTunes.

Due to my travel schedule, I am posting this one early. I hope no one minds.

Astronomical objects have a bewildering array of names. Is it M1, or The Crab Nebula, or NGC 1952, or what? Why are there so many weird names for these things?

Find out in this week’s episode of Q & BA: By Any Other Name.

Viewing options:

Watch it right here, right now!

Watch it on YouTube.

Watch it on Google video.

Download it directly from LibSyn.

Download the audio only version from LibSyn.

NOTE: If you are already a subscriber through iTunes, you may be getting both the video and the audio-only versions in your feed. This is because both versions were in one feed until last week. If you want to get only one or want to download both separately, then unsubscribe first and then click on the link(s) below.

Subscribe to AUDIO ONLY VERSION via iTunes.

Subscribe to VIDEO VERSION via iTunes.

Show notes

The Question:

The question was sent in by Teri Bootelaydi:

What is the rational behind the naming and numbering of astornomical objects?!?!

I have shelves full of astronomy books and magazines, and close to a thousand sites and ‘papers’ in my Bookmarks — and not one — NOT A SINGLE ONE — explains the logic behind these labels. It’s a nightmare for an amateur to learn.

It’s as if the IAU gets together behind closed doors and laughs at us.

Images and Links

The image of Charles Messier is from the French version of Wikipedia.

The Comet SWAN picture is from makelessnoise’s Flickr collection (usage is under the Creative Commons license). That’s a meteor streak next to it! Pretty cool shot.

The Orion Nebula image is from Space Ritual’s Flickr collection (again, Creative Commons).

The image of Sirius is from Hubble.

All the myriad names for Sirius are from SIMBAD, an astronomical database.

The Crab Nebula is from the Subaru Telescope.

Space is a vacuum, right?

Well, not exactly. It’s all pretty empty on a cubic centimeter by cubic centimeter basis, but how empty is it?

Find out in this week’s episode of Q & BA: I Am Your Density.

Viewing options:

Watch it right here, right now!

Watch it on YouTube.

Watch it on Google video.

Download it directly from LibSyn.

Download the audio only version from LibSyn.

Subscribe to AUDIO ONLY VERSION via iTunes.

Subscribe to VIDEO VERSION via iTunes.

Show notes

The Question:

The question was sent in by Walter L. Williams:

When we talk of the vacuum of space, is it a total vacuum or "pretty much" a vacuum? Could you elaborate, perhaps telling us how much matter might be in say a "liter of space"?

Images and Links

The Orion Nebula and Carina cloud images are courtesy of NASA/Hubble/AURA

Barnard 68 is from the European Southern Observatory.

The marshmallow came from my baking drawer. When I was done, I ate it.

Hey, let’s take the Moon out for a spin… but we’re too late! It already does spin!

And I can prove it. Just watch Q & BA Episode 5: Spin Doctor and you’ll see how.

Viewing options:

Watch it right here, right now!

Watch it on YouTube.

Watch it on Google video.

Download it directly from LibSyn.

Download the audio only version from LibSyn.

Once again, I’m trying something new. I’ve been asked to have two separate feeds; one for audio and one for video. Let’s see if this works!

Subscribe to AUDIO ONLY VERSION via iTunes.

Subscribe to VIDEO VERSION via iTunes.

Show notes

The Question:

The question was sent in by Mark Tillotson, of Emmaus, PA:

What would we experience if the moon was not ‘locked’ in it’s rotational period with the earth?

Would we see anything different on Earth? Would the tides be different? Would the lunar recession be different (moving away from Earth faster or slower)?

Images and Links

The essay I wrote about tides, the Moon’s rotation/revolution lock, and its recession can be found on my Misconceptions page.

The lunar phases image is from the amazing Lunar and Planetary Observation and CCD imaging website of Antònio Cidadão; specifically, his animations page.

The far side of the Moon image is courtesy NASA and the Galileo probe.

I bookmarked the site with the revolver image so I could link it here, but I appear to have lost it (it was a public site, like from a museum or government). Oh well. Don’t shoot me.