Blogs / Bad Astronomy

Today is Carl Sagan’s 75th birthday. It would be nice if he were still around to send him the greeting personally, but sadly, he died too young: in 1996 he succumbed to complications of myleodysplasia. As he himself noted, though, the progress of science — medical science in this case — kept him alive far longer than would otherwise have been possible. Up to the end, he was an evangelist of science.

And his legacy continues. His TV show "Cosmos" continues to inspire people, and the generation of astronomers who took up the cause due to Sagan’s exhortations are still looking up, looking out, and seeking what’s around the next corner. Because of Carl Sagan, we have many more scientists who not only love the field itself, but strive to express it to others. I include myself among the latter.

That’s why we celebrated Carl Sagan Day on Saturday, to honor the man and, in my opinion just as if not more importantly, to continue his work. James Randi knew Sagan personally; they were friends for many years, and so at the celebration Randi was the keynote speaker, relating stories about the man whom Randi knew as simply Carl. Below is video of Randi’s talk. It’s an hour long, but it’s more than worth your time. This was recorded off a live stream, so go ahead and click forward to about the 9:00 minute mark to get started.

This first Carl Sagan Day was a great success. We had a great audience at every talk, kids playing outside in the inflatable rocket ship bounce room, pictures from Hubble adorning the windows and walls of Broward College, and an overall sense that there is great work that has been done, with still a vast amount yet to do.

But that’s where the fun is. Sagan knew that, and I hope that you do too. And if you don’t — if you think science is stodgy, uninteresting, and doesn’t affect your life — then hopefully you have an amazing moment lying in wait for you. Maybe it’ll be a Cassini image of Saturn, or a tiny cell undergoing mitosis under your scrutiny through a microscope, or the sudden understanding from a news article about the Large Hadron Collider. There’s no way to know what precisely that trigger will be. But at some point there will come something that will jolt you, will shake you out of your complacence, and the scales will fall from your eyes.

At that moment you’ll experience what Carl Sagan did every moment of his life, that same sense of wonder and pure, undiluted joy about the Universe. I feel it too. It’s the blood in my veins, the calcium in my bones, the electricity of my eyes and ears as they relay what they detect to my brain. It’s the sense of connectedness with everything, and it’s real.

That’s what Carl Sagan taught us.

Somewhere, something incredible is waiting to be known.

My friend Bug Girl (an entomologist and Skepchick) sent me a note about a cool opportunity for U.S. east coast teachers: you can participate in a Shuttle experiment involving Monarch butterflies in space!

When Atlantis launches next week, it will be carrying some Monarch caterpillars to be taken aboard the Space Station, where they will hatch and be observed. Lots of questions will be investigated: What happens when pupae burst open in space? How will the butterflies cope? Will their migrating instinct be satisfied by moving 7 km/sec across the face of the Earth?

OK, I made up that last one, but Monarch Watch is looking to get teachers and students involved in the real science of butterflies in microgravity. But HURRY! They need your email by tomorrow, Friday, November 6! So if you’re an east coast teacher, go to Bug Girl’s blog and see how you can join in on the insecty fun.

What is the source of cosmic rays?

Seems like an easy enough question. Cosmic rays are little subatomic particles zipping across the Universe. We’ve known about them for decades, and just about any astronomer who has used a space telescope knows and loathes them; cosmic rays zap our detectors, leaving bright streaks in the images which need to be tediously cleaned out before we can do any real science. I spent a large fraction of my time with Hubble doing just that.

But what’s generating them? They seem to come from all directions in the sky, making it difficult to pin down their source. They’re moving at fantastic speeds, so they must have a huge energy source behind them. For years, astronomers have suspected that they are accelerated to high velocities in supernovae explosions as well as in the fierce solar winds from massive stars. Recent evidence has been making that supposition seem more likely.

And now new results from the VERITAS gamma-ray telescope array have added fuel to that fire. VERITAS stands for Very Energetic Radiation Imaging Telescope Array System, and it’s located atop a mountain in Arizona. When energetic gamma rays (a form of light) hit the Earth’s air, they create a shower of subatomic particle that rains down and can be detected by the telescopes.

If cosmic rays come from supernovae and massive stars, then we should see more of them coming from galaxies that have a lot of stars being born. That’s because massive stars don’t live long. A nearby galaxy vigorously cranking out baby stars will therefore have lots of massive stars making cosmic rays. As a happy by-product, those same massive stars are the ones that blow up as supernovae, giving us a two-fer as far as cosmic ray production goes.

Such a galaxy exists: M82, a weird-looking one located a mere 12 million light years away (it’s close enough to see in binoculars, in fact). The image above is M82 as seen by Hubble, Chandra, and Spitzer. Astronomers trained VERITAS on M82 and took a very, very long exposure. What they found is that is is a weak source of gamma rays, but definitely above the background level. The amount detected is consistent with cosmic rays being generated in the violent environment of the galaxy which then slam into the gas surrounding the stars, generating gamma rays. Another process, called inverse Compton scattering, is probably behind this as well: when a low energy particle of light called a photon hits a cosmic ray, its energy is pumped waaaay up, and it becomes a gamma ray. Think of it like gently throwing a rubber ball in front of a speeding truck on the highway; the ball suddenly and violently finds itself with a lot more energy.

This all may not seem like a big deal, but it is. For one thing, there are a lot of cosmic rays flitting about out there, so knowing what they are and how they formed is clearly a big piece of understanding the high-energy Universe. Also, these cosmic rays may have an effect here on Earth. Scientists have been studying how they may interact with the Earth… and while the effect, if any, is incredibly small (people still argue over whether there is anything to this at all, like cloud formation and such) it’s worth investigating.

And I want to add something that makes me smile. The cosmic rays (which, remember, are subatomic particles) from M82 were detected because while still inside that galaxy they make gamma rays, a form of light, which then travel straight to Earth. But once those gamma rays hit our air they create subatomic particles once again, which are what VERITAS detects. So there are several steps to this process, with cosmic and gamma rays going back and forth until we actually detect their effect. It goes to show that sometimes the key to our understanding the Universe can involve subtle processes piled one atop the other, and it’s up to us to carefully peel back those layers to get to the underlying processes underneath.

As promised, Brian Cox was on The Colbert Report last night, and hit it out of the park. The whole show was better than average (which is saying a lot) but Brian truly rocked!

If you missed it (and live in the States) the whole episode is online (Brian’s segment is about 13:50 into the episode). Comedy Central won’t allow embedding the whole show (sigh), and Brian’s segment isn’t separated out on the CC site, but right before he was on Colbert ragged on physics and the LHC:

In the full segment, they talk about Brian’s book Why E=mc², which was excellent. I’ll try to write a review of it as soon as I can. In the meantime, I do have to praise Colbert for his insight; as Brian points out he was correct in his ideas! I was cheering along with the segment. It still cracks me up that the smartest and most insightful commentary on TV is not from any of the "real" news stations, but from satirical shows like Colbert and The Daily Show. They have better science coverage than CNN, MSNBC and anyone else combined.

You know why science is hard and nonsense is easy?

Because as an adherent to reality, I’m not allowed to just make stuff up. Sadly, others need not follow that rule.

"An official announcement by the Obama administration disclosing the reality of extraterrestrial life is imminent", indeed. What does imminent mean? A year? 10? I’m guessing never. But as long as the antiscience advocates can use words like soon, imminent, and impending, they can keep their believers on the hook.

And why am I not surprised to see Richard Hoagland’s name in that article?

Every now and again I have to do that comical rapid-shaking-of-the-head accompanied by that wugga wugga wugga sound when I think that people actually buy into this, um, stuff. Wow.

Tip o’ the tin foil beanie to Sandra Prow.

The SETI Institute’s latest episode of the podcast Are We Alone is now up, and I talk with Seth Shostak about the idea that somehow, forces unknown (God? The Universe Itself? The Doctor? Tony Newman and Doug Phillips?) have tried to sabotage the Large Hadron Collider… from the future!

Personally, I’m not buying it, but it’s an interesting idea. The authors of a published study say that we should perform some sort of experiment before turning the LHC on to see if someone from the future is trying to contact us. But I have a better idea: let’s turn the LHC on and see if it works. If it does, then we’re done with this idea. And if it doesn’t, hand me my sonic screwdriver. There’s work to do!

[Edited to add: Well, the folks at CERN have been injecting particles into the LHC stream since Friday. They'll be ramping it up to full speed in the coming weeks, so we'll know soon enough about all this!]

According to Wikipedia, the last naturally occurring incident of smallpox (Variola minor) happened on this date in 1977:

By the end of 1975, smallpox persisted only in the Horn of Africa. Conditions were very difficult in Ethiopia and Somalia, where there were few roads. Civil war, famine, and refugees made the task even more difficult. An intensive surveillance and containment and vaccination program was undertaken in early and mid-1977. The last naturally occurring case of indigenous smallpox (Variola minor) was diagnosed in Ali Maow Maalin, a hospital cook in Merca, Somalia, on 26 October 1977.

In the 20th century, smallpox is estimated to have killed hundreds of millions of people. Hundreds of millions. Imagine the United States — the entire country, from the Pacific to the Atlantic — empty, devoid of people, dead. Smallpox wiped out that many people with room to spare.

And yet, today, it’s gone.

Why do you think that is? Homeopathy? Detoxification? Thinking good thoughts?

Nope. Vaccinations. A global campaign was undertaken in 1950, and within 30 years smallpox was struck from the face of the Earth.

Hey Jenny McCarthy, Meryl Dorey, and all you antivaxxers and your ilk: got a response to this? Still want to claim vaccines don’t work? Still want to stop people from getting them? Do you want to see this happen to children all over the planet again (WARNING – SERIOUSLY! -VERY DISTURBING IMAGE). Because if you are successful in your campaign to stop vaccinations, that’s what we’ll be facing again.

Vaccines are perhaps the single greatest triumph of modern medicine. Yet a vocal minority willing to trash facts, spin the truth, and generally spout misinformation is putting not only themselves but you, me, and everyone at risk.

Happy anniversary, smallpox, gone these past 32 years. And may I add, good damn riddance. May reason, rationality, and science-based medicine do the same for every other threat to the health and well being of the human race as well.

Tip o’ the syringe to Reddit.