They had to get their ideas from somewhere.
Yesterday, an active region on the sun – basically, a collection of magnetically active sunspots – popped off a series of flares that were actually fairly energetic. NASA’s Solar Dynamics Observatory caught the action in this video:
Neat! These shots were in the ultraviolet, where flares are easier to spot.
Sunspots are where the Sun’s complex magnetic field pokes through the surface. The field lines store ridiculous amounts of energy (did you see my BAFact for today?), and allow plasma – superheated, ionized gas – to flow along them. Think of these field lines like a pillowcase full of tightly wound springs. If one of them snaps – which can happen if they get too close to each other, for example, or when the churning surface of the Sun ratchets up the tension in the field lines beyond their capacity to restrain themselves – it blasts out its energy, which then snaps other lines, which release their energy, and so on. You get a cascade of explosions, resulting in a solar flare.
Flares can be pretty small, or hugely huge. Scientists categorize them by the amount of X-ray energy released, so we have low-energy C class, medium M class, and yikesingly X class. This flare from yesterday just edged into X class territory, so it was decent, but not too bad. Happily it was on the edge of the Sun, and the blast was directed away from Earth, so it’s not expected to affect us. For further reassurance, there have been 14 previous flares since this new sunspot cycle began a couple of years ago, and we’re still here.
However, as the Sun spins, this active region is rotating toward us. If it stays active, we could see some interesting events from it that can cause aurorae on Earth. The odds of anything bad happening – power outages, or loss of satellites, for example – are low, but not entirely zero. I personally am not too worried about it, but it’s always good to keep our eyes on our nearest star. It can pack quite a punch, and we’re still a year or so away from the peak of the current sunspot cycle.
Image credit: NASA/SDO
[I’m trying to catch up with all the news that’s been released this week while I was off lecturing in Texas. This is Part 2 of a few articles just about exoplanets. Part 1 was posted earlier.]
Astronomers have found one of the most interesting exoplanets yet: one with a very extended ring system!
[That’s an artist’s impression of the system; click to encronosate.]
The planet was discovered with the SuperWASP (Wide Angle Search for Planets) telescopes — a UK project that employs low-magnification but very sensitive cameras which can observe large areas of the sky at the same time. It orbits a young star called 1SWASP J140747.93-394542.6, which is 420 light years away. The star’s youth — 16 million years — indicates that the rings are probably the leftover remnants from when the planet formed.
The planet and its rings were discovered using the transit method: looking for small dips in starlight as a planet passes directly between us and the star. This is how the vast majority of exoplanets are found. Usually, when you graph the brightness of the star over time, the dip in the plot as the planet transits the star starts suddenly, drops to some minimum, then jumps back up (see here for example). The whole thing is usually over in a matter of hours at most.
But this planet took nearly two months to transit the star! And the dip was weird: there were multiple times the star dimmed then got brighter again, at one point having 95% of its light blocked. Even though the planet wasn’t seen directly, the most obvious explanation is a ring system similar to Saturn’s (though much larger), blocking the light. It must have gaps in the rings, like Saturn’s do, to explain the starlight jumping up again over time. Overall, four rings were detected, and they stretch tens of millions kilometers in diameter!
Saturn’s ring are only about 300,000 km across, so clearly this planet must be much more massive than Saturn, and the rings denser. It may be a little unfair to compare it to Saturn at all; it’s more like a super-Jupiter still surrounded by primordial debris. Unfortunately, we don’t know how massive the planet itself is; you need Doppler data for that and none has been taken yet. The astronomers who discovered this system, of course, are looking into obtaining Doppler data. It’s even possible the object is so large it’s actually a brown dwarf and not a planet.
Perhaps most intriguing about all this are those gaps in the rings. The easiest way to explain them is that there are objects there, moons, sweeping out the material in the rings. Saturn’s rings have gaps for this reason. In fact, there are hundreds of gaps in Saturn’s rings! These are caused by resonances: if a ring particle orbits twice for every one time a moon orbits, for example, the moon’s gravity tugs on it every time it swings by, pulling it into a different orbit. Over time, all the particles in that orbit are gone, leaving behind a gap.
If the planet itself is big, how big are those moons? Could one be Earth-sized? It’s an idea that’s been around awhile, but none has ever been seen… yet. All these super-Jupiters being found have a lot of gravity, and it’s possible they have big moons. We’re also getting better at detecting smaller objects, so it wouldn’t surprise me if that announcement is made sometime relatively soon, too!
I’ll note that the idea of looking for rings and moons is more than an idea: the Hubble observations of the star HD 209458 I mentioned the other day were taken to look for moons and rings around that planet! None were seen, but astronomers will keep trying. There are a lot of planets out there, and one thing we’ve learned is that variety is the spice of nature.
Image credit: Michael Osadciw/University of Rochester
MILD SPOILERS FOR THE NEW DOCTOR WHO. If you want to remain Whoally pure, then go away.
I just got word that the new series of Doctor Who will start on BBC America here in the States on April 17. All I know about the UK premier is that it’ll be around Easter (I may know more next week). The BBC confirms that the first three episode titles will be The Eleventh Hour and The Beast Below, both by Steven Moffat, and Victory of the Daleks by Mark Gatiss. Guest stars include Alex Kingston (River Song is back!), Sophie Okonedo, and Tony Curran.
This is pretty cool: the Lunar and Planetary Institute is planning a meeting about the use of suborbital flights. It’ll cover research, passengers, public outreach, the whole schmeer.
The Next-Generation Suborbital Researchers Conference will be held right here in Boulder on February 18 – 20, 2010. The speakers lining up are pretty good: my friend (and Apollo expert) Andy Chaikin will talk about passenger flight, former Shuttle commander Rick Searfoss, Pluto probe New Horizons chief guy Alan Stern, and people from NASA and the FAA will be there too.
If you want to participate (I suspect some space gurus read this blog…) then there is a November 12 deadline. Hurry!
I’m very interested in the use of space and near-space, so I’ll probably wind up going too. I don’t know what the future of space exploration will hold any more than the next space enthusiast does, but I’m pretty sure this will be playing a big role in it.
Reminder: Wil Wheaton will be on The Big Bang Theory tonight! I don’t know if I’ll be able to watch tonight since I’m traveling, but I’m hoping.
And folks: if you comment below, PLEASE DON’T POST SPOILERS. Mmmmkay?
A lot of people sent me notes via email and Twitter saying they were out watching the Shuttle and the ISS pass by in the sky last night when Discovery did something very odd and disturbing: there was a flash and then an expanding halo of light around the Shuttle.
My first thought when I read this was that it was an orbital maneuver — a rocket firing — or maybe a meteor coincidentally near the same spot in the sky, but it turns out to be neither: it was a waste liquid dump, when the astronauts empty waste tanks before landing the Orbiter. SpaceWeather.com has the details, including a very cool picture.
I was out last night twice to see Discovery and the ISS, but didn’t see the Orbiter either time (I think the predictions I was using were off due to the imminent landing), so I missed the show. Oh well. I imagine more pictures will turn up pretty soon, though, so keep your eyes open.
Discovery has a landing opportunity at 19:05 Eastern time (23:05 GMT) today — they’ll make the de-orbit burn at 17:59 if the weather holds up — and then another opportunity about 90 minutes later at 20:42 (00:42 GMT) if needed. As usual, I’ll be tweeting it as it happens.
On Tuesday, June 23 (tomorrow!), I’ll be in DC to talk about how the internet and social networks have changed the way we communicate science. The cool thing is, the talk will be at the very prestigious National Academy of Sciences!
The NAS has always been interested in science communication, but the advent of teh toobz has obviously changed the game. A lot of voices advocating reality are rising now that were unheard before, and the web is their (our!) medium. So they asked me to come and talk about this to the staff, and, even better they’ve opened this to the public. Matt Nisbet has scheduling details; my talk is at 12:30 – 1:30 at the NAS building (500 Fifth Street, N.W. DC).
It’s RSVP only, so if you are in the area and want to attend, contact Olive Schwarzschild at oschwarz "at" nas "dot" edu.
I don’t usually put personal stuff on this blog for a lot of different reasons, but today is a rare exception.
You see, today is my mom’s 80th birthday.
She’s been a huge influence on me. Of course, your parents are supposed to be, for better or worse, but in this case I’m going with better. My parents were really great about encouraging my siblings and me to pursue the lives we wanted (including letting me keep my giant 10″ Newtonian telescope in the corner of the living room for years — visitors thought it was a water heater), and that resulted in all of us going after unusual or non-standard careers. And, come to think of it, all of us have made major career changes at some point in our lives; I consider that to be a positive aspect since it meant we were unsatisfied with the way things were going and, rather than settle, we went off in new directions to find what it was we wanted.
My oldest brother
is an electrical engineer has a degree in computer science and now runs a computer and networking consultant business in Atlanta. My other brother’s the chief engineer for construction in a Maryland county public school system. My sister has a Masters degree in music and sang opera, for criminy’s sake! And me, I’ve had a handful of weird careers myself. Writing stuff while wearing pajamas may be the most mainstream of them.
So my brothers and sister owe a lot to my mom. I know she reads this blog (though the fire-eating and tattooing and gun-shooting stuff may have her reading this from behind the couch), and I also know she would love it if everyone here sent their best wishes to her.
Happy birthday, Mom.