Born in Arizona, moved to Babylonia,

He was born in Arizona, lived in a condo made of stone-a had a dagger made of meteoritic iron, nickel, and cobalt-a,
King Tut

—   Steve Martin, “King Tut”

I never in my life would have thought I’d pose this question, but guess what King Tut and I have in common?

I was born in Virginia, not Arizona, so it’s not that. It’s this: We both have daggers made of iron meteorites.

I bought mine (which, technically, is actually a letter opener) at a science meeting a few years ago, and it was the first meteorite-based item I ever got; I now collect meteorites and love them. It’s unclear where Tutankhamen got his (assuming it wasn't the goa’uld), but a paper published recently in the journal Meteoritics and Planetary Science shows pretty conclusively it’s wrought from meteoritic material. That’s interesting historically —for one thing, it supports many studies showing that iron was used sporadically during the Bronze Age (in this case just a couple of centuries before its end, and the Iron Age proper began in that region)— but how they figured this out is also pretty cool.

The dagger is 34 centimeters long, and has a gold handle with decorations. The blade is clearly iron of some kind, but IDing it as meteoritic has been difficult. Most methods involve getting a sample and destroying it (vaporizing it, for example), which is a problem when you’re dealing with a priceless artifact.

In this case, though, they used a non-destructive technique called X-ray fluorescence (or XRF) spectroscopy. This beams high-energy X-rays at the sample, which strips some of the atoms of their electrons. Other electrons then move around to fill the hole left behind, and emit X-rays when they do. Different atoms emit X-rays with different energies, and new detectors in portable XRF spectrometers are sensitive enough to taste those X-rays and sort them by their energies.

That plot shows the X-ray spectrum they found for the dagger. Each bump is energy emitted by a different kind of atom: iron (Fe), cobalt (Co), and nickel (Ni). Each atom emits X-rays at different energies, so each bump (technically, we call them “lines”) has its own name; thus Fe alpha, and so on. The size of each line depends in part on the amount of material present, so by carefully measuring the lines the percentage by weight of each element can be found.

They determined the dagger is about 88 percent iron, 10.8 percent nickel, and 0.6 percent cobalt. This is very much what you’d expect from a meteorite, and very different from terrestrial iron ore.

That confirms the metal from this dagger used to be part of an asteroid circling the Sun which fell to Earth some time ago. How cool is that?

But you can tell more. The specific ratios of those metals can tell you which meteorite it was, or at least narrow it down. The scientists compared their results to meteorites from within a 2,000 km radius centered near the Red Sea, and found a near match in a one-kilogram meteorite called Kharga, that was discovered in 2000. It’s not a perfect match, but it’s close enough to indicate that such objects were available to the Egyptians.

It’s been known for some time that ancient peoples used meteorites for iron, which makes sense in hindsight^*. Meteorites fall from the sky and land on the ground, where they’re easy to pick up and use. They’re unusual looking, so likely to be found by a curious passerby, and obviously denser than other rocks so that they’re bound to be kept and even cherished.

Working the metal is difficult, though, and Tut’s dagger was worked with some skill, indicating that even in the 14^th century BCE ironmongers had some practice.

I find this whole thing pretty wonderful. I’m fond of talking about how astronomy is not some remote field of science, but has an actual, physical connection with people. It also gives us insight into our ancestors millennia ago. When we look out at the stars, we are actually looking inward at ourselves. The Universe has shaped us and our civilization, and it has been our use of science that has led to understanding just how profound that impact has been.

Top o' the sarcophagus lid to Boing Boing.

^* Of all things, my first exposure to this idea was reading Philip José Farmer’s Riverworld science fiction series. Learning comes in all forms. 

Are you sitting down? Good. Comfy? Excellent. I wouldn't want you to be hurt when your jaw hits the floor watching this video. Texas Rep. Louie Gohmert, everyone:

Just in case you missed —and how could you?— here’s the fun bit:

I really wonder how many people in this body who had the ultimate power to decide whether humanity would go forward or not, whether there was an asteroid coming or something that would end humanity on Earth as dinosaurs were ended at one time--okay. We have a spaceship that can—as Matt Damon did in the movie—plant a colony somewhere. We can have humans survive this terrible disaster about to befall. 

If you could decide what 40 people you would put on the spacecraft who would save humanity, how many of those would be same-sex couples? 

You are wanting to save humankind for posterity—basically, a modern-day Noah. You have that ability to be a modern-day Noah. You can preserve life. 

How many same-sex couples would you take from the animal kingdom and from humans to put on the spacecraft to perpetuate humanity and the wildlife kingdom? 

That is why it has been called part of the natural law, natural law given by the Creator; but when we continue to abolish the first words of the Bill of Rights—the First Amendment—and we continue to prohibit the free exercise of religion, we don't have much longer to go. 

I’m not sure what’s more worrisome: That Gohmert seems so very concerned about gay space colonists in case of planetary armageddon, that he thinks his own religion is exempt from the First Amendment, or that, in 2016, a sitting member of the United States House of Representatives thinks that being gay or transgender is a “mental disorder” and “perverse.”

This might be a good time to note that elections have consequences. You put people in power, and they make laws. What they base those laws on might be their desire for religious oppression, their homophobia, their racism, their desire to please the people who fund them, or their simple desire to seize power and maintain it.

For example, in 2002 Texans elected Tom Delay, who became the House majority leader. He then led an effort, sadly effective, to gerrymander Texas District 1, which had been historically Democratic. It became heavily Republican, and Gohmert was the beneficiary of that action. Much to our nation’s embarrassment.

Elections have consequences. Choose carefully.

Tip o’ the gay spacesuit helmet to Brian Gaensler.

Update, June 1, 2016: In the perfect timing department, I just found out right after publishing this that June 2016 has been declared LGBT Pride month by President Obama. I'm guessing Gohmert won't be attending the parade.

Our Milky Way galaxy is a bruiser. It’s 100,000 light years across — a quintillion kilometers, or a million million million km if you prefer — and filled with stars, gas, and dust.

It also has several companion galaxies, smaller satellites orbiting it like the Moon orbits the Earth. These companions are far smaller than the Milky Way, but still vast to human experience. Two of them are visible to the naked eye, if you happen to live in the southern hemisphere (or the extreme southern northern hemisphere): the Large and Small Magellanic Clouds. Both are what we call dwarf irregular galaxies. The Large one (usually just called the LMC) appears to be struggling to make some sort of overall shape for itself, and is sometimes called a barred spiral, though that’s a little bit of a stretch in my opinion.

The Small one (or SMC) is a true irregular, a shapeless blob of stars and gas and dust roughly 7,000 light years across. And did I say gas? It’s thick with the stuff; huge clouds of hydrogen, helium, and assorted other elements and molecules in blobby patches throughout.

The image above shows that very well (and I shrank it down a lot to fit the blog, so seriously, check out the super high-res version for am eyeball-popping experience) It’s a combination of data taken by the Digitized Sky Survey and observations by Ignacio Diaz Bobillo and Ryan Hannahoe, assembled and calibrated by Robert Gendler. It shows the galaxy in visible light, but also using a filter that lets through the light from glowing hydrogen specifically. This strongly highlights gas clouds, especially those that are in the process of collapsing and forming stars. All that reddish cotton-candy glow all over the image? That’s where stars are being born!^*

I was stunned by the sheer number of gas clouds in the SMC. My first thought was, “Just how many stars are being born there now?”

Astronomers call this the star formation rate, and it’s usually cited in terms of solar masses per year. So if one star with the mass of the Sun is born every year, the star formation rate is 1 solar mass per year. That’s an average; you get the same number if three stars with 1/3 the mass of the Sun each are born per year.

Poking around the web, I found that the SMC has a star formation rate of very roughly 0.04 – 0.05 solar masses per year. That was surprisingly small to me given all that gas we see in the photo! The Milky Way has a rate of more like 2-4 solar masses per year.

But wait! The S in SMC is for “Small”, after all. Just looking at its stars and gas, it has a total mass of nearly a billion times the Sun. The Milky Way has a stellar+gas mass of about 50 billion solar masses, far more massive than the SMC, roughly 50 times more (if you include invisible dark matter which surrounds both galaxies, the ratio stays very roughly the same).

So all things being equal, you might expect the Milky Way to make stars at roughly 50 times the rate the SMC does. Averaging the numbers for each galaxy and dividing gives us 3 / 0.045 = 70, so the Milky Way produces stars roughly 70 times the rate at which the SMC does. Hey, that’s actually pretty close to our assumption (for astronomers, a factor of two is “pretty close”). Nice.

I’ll note that the Milky Way makes stars pretty continuously, churning them out century after century at roughly the same rate. But the SMC has had a couple of bursts of star formation in the past, probably due to interactions with the Milky Way as it orbits. The last one was less than a billion years ago when the rate may have been as a high as 0.3 solar masses per year. 

If it’s littered with gas clouds now, imagine what it must have looked like 700 million years ago, during the last burst of star birth, when it was making stars ten times faster than it is now! What a sight that would’ve been!

And as a bonus: Do see all the blobby clutches of stars all over the place (like the huge one, NGC 104, on the right)? Those are globular clusters, spheroidal-shaped collections of stars, some with up to a million stars in them! I found a half dozen without too much trouble. How many do you see? Hint: Check out the annotated version of the photo where everything is labeled. That’ll keep you busy for a while.

^* Well, mostly. Some may be the sites where stars died, blowing up, expelling huge amounts of gas into space that also glows the same colors. But those are far more rare and generally smaller than sites of star formations.

At this point, it’s painfully clear that Donald Trump is incapable of telling the truth. Listening to him talk is actually rather amazing; just by the laws of statistics he should randomly say something accurate just once, at least by accident.

Yet, here we are.

On Friday, May 27, 2016, Trump was in Fresno, California to give a stump speech. In it, he talked about water and California’s enduring drought… or did he? If you listen to him, he doesn't seem to think it’s a problem.

Here's what he said:

When I just left, 50 or 60 farmers in the back and they can’t get water. And I say, “How tough is it; how bad is the drought?” “There is no drought, they turn the water out into the ocean.” And I said I’ve been hearing it and I spent a half an hour with them it’s hard to believe.

Now it’s a little tough to parse that quotation, because he talks as if periods between sentences are a liberal conspiracy. A lot of people are quoting him as if he is saying there is no drought, but it could be that the “There is no drought” line is him quoting the farmers he was talking to. However, given the context, it’s clear he thinks this as well. Also in the full speech you can hear him quoting a farmer saying, “There’s plenty of water”.

Where to even start with something so bizarrely nonsensical? To believe there’s plenty of water in California you’d either have to be a cactus or completely, utterly oblivious to reality. Because that’s grossly wrong. Grotesquely wrong.

California is suffering a massive drought, and has been for years. As that graphic above shows, 95 percent of the state is at least abnormally dry, and over 20 percent is having an “exceptional drought”. That’s better than last year when over 40 percent of the state was exceptionally dry; a better snow pack in the Sierra Nevadas this year has helped in northern California somewhat. Still, many of the reservoirs are below average levels; some far below, and the southern part of the state is in dire straits (so to speak). Things are not good, and projections show the drought will persist through at least August. Probably far longer.

So Trump’s claim that there’s plenty of water is just more of the lies he’s peddling.

Part of what he’s talking about in that speech deals with water being diverted from farms to rivers to protect wildlife such as the delta smelt and salmon. That’s a very complicated and thorny issue, and I don’t pretend to have an answer here. But Trump certainly doesn’t either, and simply saying, “If I win, believe me, we’re going to start opening up the water so that you can have your farmers survive,” as Trump did in his speech, is ridiculous. The laws won’t let him do that, for one thing, and for another it’s unlikely to help in the long run. California simply doesn’t have an infinite supply of water.

This is a situation that calls for a lot of political compromise, nuance, and long-term thinking. Trump has none of that.

You know what else this situation needs? At the very least, an acknowledgment that climate change is real. Environmental scientist Peter Gleick and climatologist Michael Mann wrote a commentary in the Proceedings of the National Academy of Sciences, saying there is “accumulating evidence that anthropogenic climatic changes are already influencing the frequency, magnitude, and duration of drought in California.”

Yet Trump denies climate change even exists. He hired a flat-out denier as his energy advisor, and has made it clear he thinks global warming is a hoax.

Later on in his speech, talking about the water shortage and getting more water to the farmers, Trump had this to say: “We’re gonna get it done. We’re gonna get it done quick. Don’t even think about it.”

Indeed, that should be his motto. “Don’t even think about it.” Because, apparently, that’s the last thing he wants anyone listening to him to do.

On Friday (May 27, 2016) SpaceX launched a Falcon 9 rocket with the THAICOM 8 satellite into orbit. The launch went off right on time (after a one-day delay due to an unusual reading from the upper stage on the Thursday launch attempt), with the Falcon roaring into the sky, the 25^th in the Falcon 9 line to do so.

It was also the fifth time in a row SpaceX attempted to land the first stage booster back on Earth, and as hoped the booster successfully touched down on the floating drone ship Of Course I Still Love You about nine minutes after launch.

The landing was, as usual, pretty spectacular, but a few hours later SpaceX released this, and I have to say it’s just about the coolest thing I’ve ever watched: Time-lapse footage from the booster itself, the camera pointed down, as the rocket comes all the way back from space and lands in the Atlantic!

Seriously. Holy wow.

So what did you just see? The rocket has two stages. The first stage boosts the upper stage (which has the payload on top protected inside a fairing) to get it most of the way up above the Earth’s atmosphere. Then to save weight, the first stage is dropped, and the second stage takes over, boosting the payload into orbit.

In the past, most rockets just drop the first stage into the ocean. But the plan from SpaceX is to recover the first stage, clean it up, and reuse it, thereby saving many millions of dollars over building another one from scratch.

This isn’t easy. The first stage is moving very rapidly, many thousands of kilometers per hour in an arc to the east over the ocean. It uses cold jets (basically compressed gas) to flip over and point its bottom into the direction of motion, then uses a re-entry burn to slow its initial motion, and air drag to slow itself further. The waffle-looking steering fins are used together with more cold jets to maintain the correct attitude (orientation) as it descends back toward Earth. The huge pressures involved cloud the view for a moment, but then it clears and you can see lines of clouds over the water, then —quite suddenly, it seems—the drone ship appears, and the booster burns again in the last few seconds to slow for landing.

This landing was particularly difficult; the satellite had to be boosted to a geosynchronous orbit, which is much higher than low Earth orbit, so the rocket had to travel must faster. That meant the landing was harder than usual, and the SpaceX team was cautioning everyone it might not work. It did, but perhaps not perfectly; the booster appears to be leaning to one side after touchdown. There is a compressible aluminum honeycomb structure inside (called a crush core) to absorb some of the energy of landing, and it took the brunt of the landing impact; that’s most likely why the rocket was leaning. The good news is the core can be replaced once the booster is back at the SpaceX facility in Florida.

Moments after watching the booster land live on the SpaceX video feed, I wondered to myself if we’d ever get used to something like this; seeing a rocket from space come back to land much like the scifi movies I used to watch as a kid. I hope it never gets old.

Or, as my colleague, astronomer Alex Parker put it:

The next SpaceX launch is scheduled for June 16, and will be another communications satellite.

On Sept. 8, 1966, NBC aired the first regular episode of a new TV show called Star Trek. It had a bit of a rocky beginning, and had a rocky end three years later. But like Spock himself it would be resurrected and go on to become a major force in popular culture.

I don’t need to give you details; if you read my blog, you probably know them as well as I do. This year marks the 50^th anniversary of Trek, with more than 700 episodes and a dozen movies covering that time span.

Holy cripes. That’s a lot of Trek! But hey, it’s well-loved, including by me. And that’s why I’m as happy as a tribble in an overhead bin of quadrotriticale to let y’all know that I’ll be at the Star Trek: Mission New York convention to celebrate the show’s golden anniversary.

The con is kind of a big deal. Actors from all the series will be there; just look at the guest list: William Shatner, Kate Mulgrew, Michael Dorn, Terry Farrell, Jonathan Frakes, Marina Sirtis, and lots more … including me.

Writing that is strange but also good.

The con will be from Sept. 2–4 at the Javits Center in Midtown Manhattan. We haven’t ironed out the details of what I’ll be doing just yet, but I expect it’ll include talks about science and astronomy (Trek related? Count on it!) and panels as well. I’m hoping to do something with some of the actors, too, but all that is TBD.

Given that this is part of the huge 50^th anniversary celebration, I’d urge you to get tickets early if you want to go.^*

I’ve got some other things I’m doing for the big anniversary as well, and I’ll let you know here and on the usual venues when those come up. I’m terribly excited about all this. Trek really was a big inspiration for me (proof), and now to be able to be a part of it in some small way is just a dream come true. My sincere thanks go to my friend Holly Amos for making this all possible, too.

P.S. If you're wondering about the picture of me, it's a crop from this. The full story is pretty cool. 

^* Boldly, of course.

People love a good “David versus Goliath” story, especially when David is an outsider, a lone voice against a big government agency that he’s accusing of being incompetent and wasting money.

The problem with that narrative is that sometimes David is wrong.

Nathan Myhrvold is a billionaire, the former chief technology officer at Microsoft, and holds a Ph.D. in physics. He has a scientific background, obviously, and recently became interested in the search for near-Earth asteroids, the kind that get close enough to our home planet to be a threat.

After doing some of his own research, he thinks that a team of scientists at NASA/JPL and Caltech have made serious errors in measuring the properties of asteroids. And he’s gone farther than that: He’s accused them of making “colossal error[s],” and made hints of fraud.

That’s an extremely serious accusation. It’s also, in my opinion, grossly wrong (NASA also issued a response backing up the scientists). After considering his research, I have concluded that the team is not in error, Myhrvold is.

The team of scientists is working on a potential NASA mission called NEOCam—the Near-Earth Object Camera—to map out the locations, orbits, and physical characteristics of near-Earth asteroids as a way to systematically determine what threat they pose to our fair planet. To do this, the scientists need to understand how their telescope operates; that is, if it sees an asteroid, how do you convert that brightness measured to a diameter? The size of the asteroid is a critical factor; without that it’s very difficult to understand much else about it. Over time, the team has published several papers showing how they make this calculation, using methods used before for earlier satellites, including NEOWISE, the predecessor of NEOCam.

Myhrvold, wanting to explore this topic himself, set about trying to replicate their results on his own. What he found, though, was that his numbers for asteroid diameters disagreed with the results from the team of scientists, sometimes by a huge margin.

One of them was wrong. Which one?

Myhrvold contacted the team, including Amy Mainzer, the NEOCam principal investigator, who has a long history of publishing scientific papers in the asteroid discipline, in order to discuss his ideas. (Full disclosure: I have known Amy for many years and consider her a friend. I talked with her about Myhrvold’s claims, and she was very helpful in pointing out references and explaining some of the physics and mathematics involved.)

At this point, the accounts diverge. Myhrvold says the team was not cooperative about their work and gave him “cryptic” answers to his questions.

Mainzer told me a very different story. She said she worked with Myhrvold multiple times, trying to show him where some of his ideas were either incorrect or not applicable to the work they were doing, but he remained defiant. She pointed out specific errors, but despite that the errors remain in his work.

The errors she mentioned are various, including his confusing diameter with radius in his calculations and using a model that incorrectly determines diameters. For his part he says their model doesn’t include some basic physics, and that some of their numbers are suspicious.

So what’s going on? Other articles cover some of the basic claims (see "further reading" at the end of this article), but I want to take on some of the science claims.

The Light and the Heat

Myhrvold claims that the physical model of asteroids the team uses doesn’t work and that they ignore “basic physics.” Now, setting aside the rather bizarre idea that an entire team of professional scientists at JPL and Caltech might not understand undergraduate-level physics, his claim that their model doesn’t work is simply wrong. Worse, it’s his own model that falls short.

The basic goal here is to determine the diameters of asteroids. How do you do that? The idea behind NEOCam is that it will use very sensitive detectors to measure the amount of infrared light the asteroids emit. Anything warm emits infrared light, and the amount of light an asteroid gives off depends in part on its size. By measuring different colors of infrared, complicating factors (like reflectivity) can be accounted for, and the diameter found.

To make sure they’re doing it right, the NEOCam team looked at asteroids for which the diameters were previously known (that part’s important). There are quite a few with accurately measured diameters; for example, some have been pinged with radar, which yields very good results for asteroids that get near the Earth. Others have had their sizes measured using occultations: Sometimes an asteroid will pass directly in front of a star, blocking its light as seen from Earth. Knowing the velocity at which the asteroid moves around the Sun together with the length of time it blocks the star gives you its size.

NEOWISE (the earlier satellite) observed these asteroids. The team then used the known diameters to create a model (a mathematical equation) of how the light is emitted. That way, they can then observe other asteroids with unknown diameters and use their brightness to measure their sizes. This is the model they’re using for NEOCam.

This is the model Myhrvold claims is wrong. However, the asteroid diameters found by the NEOWISE team agree very well with previous satellite measurements. NEOWISE looked at many of the same asteroids as an earlier mission called IRAS—a couple of thousand of the same asteroids—and found that the diameters calculated for those asteroids matched the measurements using IRAS to about 10 percent. Not only that, measurements using a Japanese satellite called Akari also yielded similar results, and all three agree well with the radar and occultation measurements.

That’s a very good indication the NEOCam team is doing things right.

Despite this, Myhrvold disagrees. He says the team is ignoring basic physics, and the diameters they are getting are wrong.

Myhrvold has written a paper with his results, and when I read it, it became clear to me that this accusation is based on a false premise. He is trying to calculate asteroid diameters starting with basic physics (from the ground up, so to speak), while the NEOCam team is doing it empirically, based on observations (so, from the top down). In the latter case the physics is built in to the way the model is generated.

Here’s an analogy: Imagine a quarterback trying to throw a football into a receiver’s hands. An accomplished quarterback has thrown the ball thousands of times, and already knows by feel and muscle memory how to throw the ball, giving it the right speed, direction, and spin to complete the pass.

What Myhrvold is trying to do is start with the physics of motion, trigonometry, momentum transfer, air drag, and so on and then telling the quarterback how to throw the ball.

But the physics is built in to the quarterback’s experience. The passer doesn’t need to calculate all the physics to complete the pass. If we humans had to do the calculus every time we wanted to move, we’d be frozen stiff. So Myhrvold’s accusation that the NEOCam’s team ignores basic physics is incorrect.

Worse, Myhrvold’s model is wrong. He published his results in his paper, and the numbers he gets are way off. For example, in Figure 21, he uses his model to calculate the diameter of the asteroid 295 Theresia. The known diameter of that asteroid is about 28 kilometers. Myhrvold gets a diameter of 660 kilometers, more than 20 times too big (if he were correct, it would be the second largest asteroid known)! Other examples with similar erroneous diameters can be found. It’s worth noting that other groups have used the NEOWISE data to compute their own models and have had no problems.

Let me be clear here: If you are accusing scientists of messing up the single most important thing they’re trying to measure—an asteroid’s diameter—you’d better get that right yourself. Myhrvold didn’t.

There’s more. For example, Mainzer told me that he confused radius for diameter in several places in his work—which she pointed out—but those errors remained even as he updated his paper. She also told me he based some of his numbers on an old paper about IRAS that had a systematic error in it, one that overestimates the sizes of asteroids.

Despite his own errors, he is accusing the NEOCam team of being wrong.

But it gets worse.

Cut and Paste

Myhrvold wrote what’s called a “white paper,” an overview of the situation as he sees it using simpler language. In it, he notes that some of the diameters for asteroids the NEOCam team calculated are exactly the same as found by an earlier mission. Like, exactly, to several decimal places. Because the chances of this are essentially zero, Myhrvold speculates that the NEOCam team may have had a bug in their code that copied the diameters from the earlier results and propagated it to subsequent results.

Or, he goes further: He speculates that maybe this is due to fraud.

Yes, fraud, as in knowingly faking these numbers. This is a stunningly serious accusation. But there’s a much simpler explanation about the duplicate numbers. I asked Mainzer about this specifically. She told me the numbers are the same because they are copied, but it’s not due to fraud. The mathematical model they use does indeed calculate the diameter, as well as several other important variables that are initially unknown (for example, how reflective the asteroid is in visible light and infrared light). However, if the diameter has already been accurately measured in other ways (radar, occultations or from previous satellite measurements), they can use that number to better calculate the other variables.

This technique is discussed in a paper published in 2011. Myhrvold acknowledges that but then says this is never mentioned in subsequent papers. If true, that would make it seem like the team, in those subsequent papers, is claiming the diameters were calculated using their model, and were not actually from previous measurements. Hence his suspicion of fraud; in fact in his white paper he goes on at length about this. However, as just one example, in this subsequent paper by the team (in Section 3, first paragraph), they clearly reference the first paper describing the method they use, including using measured diameters if available to better nail down the other variables.

In other words, Myhrvold is wrong. They do in fact discuss how they got the diameters in later papers. He may have simply missed this in the later paper. But either way he should have been more diligent in discussing this with the NEOCam team, especially given the seriousness of his accusations.

If you mention fraud, even as a possibility, you’d better have solid data to back it up. From what I’ve seen, Myhrvold’s claims don’t even come close.

There’s one final thing, and it’s important: Myhrvold’s paper has not yet been peer reviewed. This is a critical step in the scientific process: Other scientists look over the paper and make sure it has the proper methodology, it doesn’t have errors, it’s relevant, and more. They make suggestions to the author, who then rewrites the paper (or redoes the research if necessary), and resubmits it. If the reviewers approve, it gets published in a journal.

The peer review process is absolutely necessary to vet work from start to finish, but Myhrvold’s paper has not yet gone through this process. It may not be foolproof, but it’s at least likely to catch errors that are hard for the author to see (like his own erroneous asteroid diameter calculations). An outsider’s opinion can sometimes be valuable.

Despite that, he issued a press release, which is unconventional to say the least. This is sometimes done when a team wants the general community to contribute and comment, but that’s not what Myhrvold is doing. He’s using it as a platform to make accusations that have not been thoroughly checked. It lends a bad smell to what he’s done.

I know this is a complicated issue, but it’s an important one. Questioning results is fine, if it’s done in good faith and by someone who is well-versed in the subject. Myhrvold has cast himself as the outsider with a unique perspective, as David. But in this case, there’s a reason Goliath is, well, Goliath. The NEOCam team has the data, they’ve been open about their methods, and everything they’ve done is online and available for scrutiny.

I’ll be very curious to know what happens once Myhrvold’s paper is peer reviewed. I hope he’ll be as public about it then as he has been up to now.

Further Reading

Because this topic is complex, here are few links to other articles about this to help you parse it all:

• The New York Times article (which is sympathetic to Myhrvold’s claims)
• An article critical of Myhrvold in the Washington Post
• The NASA response
• A neutral synopsis at Inverse
• A neutral synopsis at Science (the comments are interesting too)
• An occultation astronomer opinion critical of Myhrvold on the Minor Planet Mailing List
• A member of the NEOCam team also posted to MPML with a critical look at the claims

In early 2012 a mystery literally erupted on Mars. Well, above it.

Amateur astronomers viewing the Red Planet from Earth noticed weird features on the limb of the planet (the edge as seen from Earth) in March and April 2012. They appeared to be clouds or plumes of some sort, but they were huge, and several hundred kilometers above the surface of Mars. No cloud has ever been seen that high, nor is there any obvious way to make one or get one there.

The features were definitely real; others have been seen (including with Hubble). Lots of ideas were considered—volcanic plumes, aurora, and so on (though Martian war machines were ruled out fairly quickly)—but nothing quite fit.

Now though, astronomers analyzing data from the Mars Express orbiter may have found a solution. Mars got hit by a solar storm.

Mind you, this isn’t conclusive, but it’s promising. Here’s what’s what.

A solar storm is when the Sun throws a magnetic tantrum, blasting off huge clouds of subatomic particles. These events carry a great deal of energy, and their own magnetic field. If they hit the Earth and interact with our magnetic field they can cause aurorae, blackouts, and other issues.

Mars doesn’t have a strong magnetic field, but it’s there; it’s only a couple of percent as strong as Earth’s, mostly due to magnetized rocks left over from when Mars did have an actively generated field (which has since shut down). And, in fact, the magnetic field is known to be a bit stronger over the region where the mystery plumes were seen.

A Mars plume spotted on March 20, 2012. Photo by W. Jaeschke.

Mars Express has been orbiting the planet since 2003, and is equipped with an instrument called ASPERA-3 that studies the interaction of particles from the Sun with the Martian magnetic field, and another one called MARSIS that uses radar to study the atmosphere and look for water under the surface. Looking over the data, scientists found that there were large space weather events around the same time both plumes were seen.

They did not see any obvious effects of this in the Martian ionosphere, the high altitude layer of the atmosphere where the molecules are stripped of electrons and become ionized. This is where you’d expect to see the biggest effect, so that’s a little odd, but it’s also known that the ionosphere in that region of Mars is “disturbed” due to the magnetic field there, so it’s hard to identify anything that would make it even more jinky.

Interestingly, Hubble observed a plume like this in 1997, and it turns out there was also a solar storm that might have hit Mars just before that observation was made. It’s not certain, but it’s compelling.

So what causes the plume? We know that the Martian atmosphere is being slowly stripped away by the solar wind, the more or less continuous stream of subatomic particles blowing off the Sun. Although the details are complex, and not fully understood, what may be happening here is that a storm from the Sun accelerates that process, compressing the Martian magnetic field, exposing the upper atmosphere to the direct effects of the storm. This allows more of the atmosphere to leak into space than usual, which we see as the plumes.

Mind you, this is still fairly conjectural; the evidence is indirect and circumstantial, but it does fit the idea that the storms caused the air over Mars to be extra leaky. Storms like this are rare, and detailed observations of Mars from Earth aren’t done around the clock, so they can miss the effects. Even orbiters around Mars itself may be in the wrong place at the wrong time to catch the effects.

The only way to know for sure is to catch one in the act. The best witness for that would be orbiters on the spot, but even observers from Earth can be crucial. Like seeing asteroid impacts on Jupiter, the more people we have observing Mars the better.

It makes sense to me. It’s easy to believe that in the early years of the 21^st century that world would be watched keenly and closely; across that gulf of space, intellects vast and warm and sympathetic would regard Mars with curious eyes, and slowly and surely draw their plans to understand it.