2015年10月31日 星期六
Ghosts and Star Trails
Halloween Asteroid Is Bigger Than Expected, And Also a Giant Dead Comet Skull.
Last week, I wrote about a smallish asteroid that would be passing relatively close to — but still well away from — the Earth on Oct. 31. Hey, that’s today! Yup: It’ll pass us at 17:05 UTC, when it will be at closest approach, about 480,000 km (300,000 miles) away, farther than the Moon.
As I mentioned in that earlier article, astronomers were planning on pinging it with radar pulses from the Goldstone radio telescope, and they also used the Arecibo radio ‘scope in Puerto Rico. Those latter observations have been done, and they produced an animation of the asteroid showing it rotating:
The observations indicate it spins roughly once every five hours. It doesn’t appear to have any moons, as many small rocks do. It’s also bigger than expected, about 600 meters across. That happen; it’s hard to get the size from just optical observations. We measure its brightness and distance, and then its size is inferred from that. But a dark rock can be bigger, and a shiny one smaller, with both looking the same brightness.
TB145 was a bit darker than expected, so it’s actually bigger than first thought. It only reflects about six percent of the light hitting it, which is pretty dark. That indicates it may be the husk of a dead comet, which tend to be darker on average than asteroids. That would also explain the weird orbit I wrote about last week; it's more short-period comet-like than asteroid-like, really.
Also, I want to point out that the animation above isn’t actually a picture as you normally think of it, because the radio telescope was using radar to map the rock. I’ve explained this before:
Mind you, the radar data is a bit weird. It’s not showing you an actual picture of the asteroid. The vertical axis is showing distance to the asteroid—if there’s a hill you’d see it poke up toward the top, and a crater would be a depression. The horizontal axis, though, is actually the velocity at which the asteroid is spinning. The faster the rock spins, the more smeared out it is left to right; one that doesn’t spin at all would look like a vertical line. I know, it’s weird, but it’s the way this kind of radar observation works.
Emily Lakdawalla at The Planetary Society has a much more detailed explanation.
And one more thing I can help but notice: Given today’s date, how cool is it that the first frame of the animation makes the asteroid look very much like a skull?
Mwuhahahahaha. Happy Halloween!
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2015年10月30日 星期五
Examining Staff and Board Member Salaries at CASIS
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The Witch Head Nebula
Dawn Journal: A Bounty of Data
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Journey to Space
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NASA Awards Launch Services Contract for Next Tracking, Data Relay Satellite
October 30, 2015
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Potentially Good Budget News For NASA
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Close View of Saturn's Moon Enceladus From Oct. 28 Flyby
Guilty Plea in LaRC Computer Security Case
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UPDATE: Rep. Lamar Smith Ramps Up His Climate Conspiracy
On Monday, I reported on a slimy attack on the National Oceanic and Atmospheric Administration by Rep. Lamar Smith, R-Texas. Smith is Chair of the House Committee on Science, Space, and Technology, and a man with his head firmly in the sand when it comes to global warming — an issue the NOAA studies very carefully.
However, because the NOAA understands that global warming is real, and has said so, they have become the target of Smith’s ire. He has used his power of Congressional subpoena to coerce the head of the NOAA, Kathryn Sullivan, to hand over all data and emails from scientists on their use of global satellite data. This is clearly a fishing expedition; he’s looking for ways to humiliate the agency, and also to tie them up in administrative knots.
In a very harshly worded letter from his co-Committee member Eddie Bernice Johnson, D-Texas, she accuses him of overreaching and abusing his power, noting (correctly) that neither he nor his staff is qualified to examine the data.
To me, this stinks of McCarthyism.
But now there’s more news.
Nature is reporting that the NOAA is refusing to comply with Smith’s outrageous demands, and “has no intention of handing over documents that reveal its internal deliberations.”
YES. This is precisely how it should be, and Smith’s gross overstepping of bounds is proof of that. If the NOAA hands over the documents, then they are acquiescing to political pressure, partisan political pressure, I’ll add, which is completely removed from the scientific process. And given Smith’s clearly anti-science view of global warming, this pressure is antithetical to the scientific process.
I can’t stress enough just how distant from reality Smith is here. His view is literally that the NOAA is purposely doctoring results to make it seem as if the planet is warming. After the NOAA announced it wouldn't kowtow to such nonsense, Smith’s office released this statement:
It was inconvenient for this administration that climate data has clearly showed no warming for the past two decades. The American people have every right to be suspicious when NOAA alters data to get the politically correct results they want and then refuses to reveal how those decisions were made. NOAA needs to come clean about why they altered the data to get the results they needed to advance this administration’s extreme climate change agenda. The agency has yet to identify any legal basis for withholding these documents. The Committee intends to use all tools at its disposal to undertake its Constitutionally-mandated oversight responsibilities.
Holy. Wow. For years I have been stressing that belief in anti-science has very real consequences, and now here we are. The Chair of the House Science Committee is attacking a science agency because of a conspiratorial belief that is utterly wrong.
His claim that the world isn’t warming is simply wrong. The so-called “pause” in warming has been shown not to exist, and it goes well beyond just NOAA data; multiple agencies around the world have data to show this (see, for example, this, and this, and this). We’ve known this for years now, and in fact not only is there no pause, but warming hasn’t even slowed.
As for “altering” data, that’s laughable. Data isn’t some revealed knowledge from scientific instruments; it’s made of measurements and is therefore subject to all sorts of issues that can artificially bias the results. What Smith calls “altering” scientists call “calibrating” or “normalizing” or "removing the bias from". For example, some temperature readings may have been made using different methods, different instruments, and those have to be adjusted to each other to account for the difference. That's precisely what NOAA scientists did in this case.
This is a common, standard, and wholly necessary scientific practice, not some nefarious scheme to cater to the White House’s agenda. Even funnier is that the adjustments made to the data are very small, and do nothing to change the very clear fact that we’re heating up.
The fact that Smith can’t or refuses to understand this very, very basic idea makes me even more upset that he is in charge of Congressional oversight for so many scientific agencies. It’s appalling that it’s come to this.
Oh, and by the way? Those temperature data from the NOAA are already public. Given that this current GOP rails against government waste, this is doubly ironic.
The Union of Concerned Scientists has more about this, as does Roll Call.
Mind you, I am all for accountability and oversight (here’s an excellent example, though not one I bet Smith would approve of). That’s not the issue here. The issue is the overreach of such demands from a Congressional Committee that clearly has no grasp of what it’s asking for, and is therefore grasping at straws.
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2015年10月29日 星期四
Orb-3 Failure Report Released
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IC 1871: Inside the Soul Nebula
ISS Daily Summary Report – 10/29/15
October 30, 2015 at 01:01AM
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Mastcam-Z: The Future of Stereo Imaging on Mars
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Crescent Pluto
NASA and the folks on the New Horizons spacecraft team just released a photo of Pluto, and I can say without fear of exaggeration that it is the most stunning shot of the tiny world yet.
Ready?
Are. You. KIDDING. ME?
This shot was taken when New Horizons was just 18,000 km (11,000 miles) from Pluto, just 15 minutes after closest approach. A piece of this image was released back in September, showing a part of the crescent, but after better processing this represents the whole view by the Multispectral Visual Imaging Camera in the instrument playfully called Ralph.
Once I picked my jaw up off my desk, I was able to start poking through the image. First off, make sure you grab the ridiculously huge 8888 x 5000 pixel version of this, because holy yikes.
The Sun was off to the right and far, far behind Pluto in this shot, over five billion kilometers away.
Starting at the lower right of the crescent you can see the relatively smooth Sputnik Planum region, part of the “heart” of Pluto. Going around the crescent to the upper left (west) are higher features, mountains up to 3,500 meters high. They would fit right in with the Colorado Rockies… except these mountains aren’t rock, they’re frozen water ice.
On Earth, an ice mountain this big would collapse under its own weight. But Pluto has lower gravity, and at -230°C water ice is as tough as rock on Earth.
In the big version, you can see the long shadows cast on the frozen landscsape by these and other higher features. It's magnificent.
You can also see Pluto’s extremely thin atmosphere of nitrogen, methane, and carbon monoxide. The striping is real! It’s due to layers of haze, molecules created when ultraviolet light from the Sun reassembles simpler molecules in the air and on the surface.
There are vast amounts of science in this photo, so much to see and learn about this distant place. And you know how excited I am about that.
But just look at it. That’s Pluto.
Our Universe is beyond beautiful. It is an exquisite work of art, one that we can see through science, understand through science, and appreciate through science.
In so many ways, the two are, quite simply, the same thing.
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Spacewalk Selfie
At Mars Workshop, Science and Human Spaceflight Find Common Ground
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From the Earth to the Moon… in One Minute
I recently wrote about the huge archive of 8400 photographs from the Apollo Moon missions released on Flickr. Put together by Kipp Teague, it’s a great way to spend some time looking over one of the greatest moments in space exploration history.
If you don’t have a lot of time, then The Planetary Society put together a <tl;dr> version of it: all the Apollo 11 photos combined into one short video:
When I first saw this on my pal Ariel Waldman’s Facebook page, I figured it would just be a rapid-fire compilation of pictures almost too fast to comprehend. But Merc Boyan, Media Producer for the society, made this eminently watchable, timing the music and photos — including some strategic pauses — to create something that, somehow, is more than the linear combination of its parts.
In fact, the photo archive has inspired all sorts of artistic endeavors by people to create interesting — and wildly different — takes on bringing these still images to life.
Vimeo user harrisonicus created a trippy video made from haphazardly collected images from the archive. Well, mostly haphazard; it shows a trip from the Earth to the Moon in chronological order, but using photos from different missions along the way. So you might see a shot of the Earth from Apollo 12 right after one from Apollo 16 (showing the Earth roughly the same size, as if you're the same distance from it, but in wildly different phases). He set it to some video game music, and the result is rather endearing.
Tom Kucy created a more serious and dramatic take by tweaking the photos a bit, animating some, tilt-shifting others, highlighting them as high (literally) art. His video is immersive and enthralling.
I love the dedication and enthusiasm people have for this. Hundreds of millions of people watched the Apollo missions as they happened, and I was one of them, though only a small boy. The effect on me was profound, and clearly, these missions still have a long reach. Given that about 400,000 people worked for a decade to put a dozen men on the Moon and return them safely back to Earth, perhaps this archive and these videos are a metaphor for the project as a whole… and a reminder what we can do when we reach for the stars.
Tip o' the spacesuit visors to Wired for the second two videos.
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Doubts About Crew Health on NASA's #JourneyToMars
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Spectacular Martian Dune
When I wrote my review of the movie The Martian, I mentioned how realistic the landscapes were. Much of the literally other-worldly scenery was based on images taken by the HiRISE camera on the Mars Reconnaissance Orbiter, which can resolve objects on the surface of the planet down to about a half meter.
I may have missed it, but in the movie I don’t think they showed any dunes. There was a lot of sand, lots of texturing in it like ripples, but I don’t remember seeing any large-scale dunes.
Too bad. Because Martian dunes are jaw-droppingly beautiful. If you don’t believe me, then take another look at the photo above, and also check it out in super-duper high-res, because wow.
That is what’s called a barchan (pronounced BAR-can) dune; a horseshoe-shaped sandpile. In this HiRISE shot, the wind is coming from the (very slightly upper) right, blowing particles to the left. If something blocks the wind a little bit, like a rock or other outcropping, the sand piles up. The wind then splits, forming a bow wave pattern around the obstacle, and the sand follows suit.
When it gets tall enough, the sand will flow down the back of the slope, creating a sharp peak more-or-less perpendicular to the direction of the wind, so it too follows the bow shape. Irregularities in the dune surface force the wind to flow up and down in waves, creating the ripples in the dune. The inside curve of the dune is in the lee of the wind, so the sand sliding down there creates a much smoother dune surface.
The color is gorgeous, but I’ll note it’s not what your eye would see if you were flying over Mars. The actual image is the combination of a red image (shown as red) and one taken with a blue-green filter (shown in green, since that filter lets through mostly green light). To make the red-green-blue image, the blue color is approximated as a mathematical combination of the green and red image.
However, this image is telling us there’s a lot of red in the dune, most likely due to very fine grain dust. Roughly speaking there are two kinds of grains on Mars: sand, which is millimeter-scale grey volcanic basalt, and dust, which is much finer (like talcum powder) and has a lot of iron oxide in it. Iron oxide is more commonly known as rust, and that’s why Mars has so much red to it.
This dune is part of a much larger dune field, and as the image release points out, the surface under the dune field is just as interesting as the dunes themselves. It looks fractured and has resisted wind erosion, so it must be made of tougher stuff. It’s likely very old bedrock. The red region on the right must be sprinkled with dust, while on the left it’s greyer, meaning less dust. In the larger scale pictures (warning: 200 Mb file!) you can see that this dune sits at the edge of the dune field, upwind (to the right) of most of the dunes. Since that’s also where the grey/red line is in the surface, I’m guessing there’s some surface sloping going on here.
When I see pictures like this, I have to chuckle. Years ago, I used to think Mars wasn’t terribly interesting or pretty. In my defense, all the photos we had were low resolution, so it looked rather dull. But I chalk this up more to a failure of my imagination. Now that we have better tech spying on the planet, it’s obvious just how gorgeous it is. I hope I’ve learned my lesson; now when I look at a photo of some object that doesn’t have a lot of features, I wonder what amazing thing lurks there that we just barely can’t see.
The Universe isn’t actively hiding anything from us. It just is what it is. We have to be motivated to dig deeper, see better, to uncover its truth.
More about Martian dunes:
Federation Scum Is Attacking Mars!
Dune Mars
Saharan Star Dunes
Desktop Project Part 17: Sculpting Martian Dunes
Crash Course Astronomy: Mars
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2015年10月28日 星期三
Tweeting From Space - In 1968
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ISS Daily Summary Report – 10/28/15
October 29, 2015 at 12:42AM
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Congress Makes Progress on Commercial Space
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Talking About Asteroids on SLOOH
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Charles Elachi Retiring As JPL Director
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Bolden's Roadmap To Mars (Video)
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A New Budget Deal and a Best Case NASA Budget for 2016
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SLS/Orion Gets a Lobbying Organization in Washington
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Conan and I Share a Little Oxygen Dihydride
Via Twitter yesterday, I found out I was on another late night talk show and I didn’t even know it!
This is actually pretty funny, and doesn’t need any setup:
I’ll admit I cringed when I heard Conan make the joke, but not as much as I cringed at the last line by Dean (the chemistry guy). Ouch.
Still, nicely retorted, Conan. And, "greatest scientists in the world"? I blush.
And I had to laugh; seeing my friends David Grinspoon, Michelle Thaller, Dan Durda, Neil Tyson, Bill Nye, and Alex Filippenko in there was pretty cool. Looks like they raided footage from How the Universe Works and Outrageous Acts of Science. Too bad they couldn’t get Hakeem Oluseyi in there, too!
And Conan, Andy: If you see this, contact me. I have a wee bit of experience doing late night… and I can play harmonica, too.
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Colors After the Storms
A Cosmic Halloween Gallery: Things That Go “Boo!” in the Night
For Earthlings, Halloween brings candy, costumes, and spooky decorations. But the Universe can orchestrate some haunting of its own. In 2011, Phil Plait published gallery of the Universe’s scariest photos. The original is reprinted below.
Halloween is coming, and while people are out trick-or-treating or enjoying a costume party, the Universe will continue to go about its business.
The business of DEATH, that is. Black holes will continue to tear apart stars and gorge themselves on the tasty, gooey insides. Galaxies will erupt with high-energy radiation, blasting out killer rays for hundreds of thousands of light years. Giant clouds of gas will collapse, form stars, and promptly have their interiors eaten out from within.
The Universe is scary, and even scarier on Halloween. And I can prove it to you, with a gallery of eerie and spooky images I hand-picked just for you. So turn down the lights, play some creepy space sounds, and enjoy. And if you get a chill down your spine while you peruse the gallery, why, I don't blame you. After all, Halloween is for make-believe ... but what you're seeing is very, very real.
Is this a moaning skull, aflame with Halloween madness?
Actually, it's something far scarier: a gigantic black hole gobbling down matter and spewing out vast amounts of high-energy radiation.
In the heart of the Perseus cluster of galaxies lies the monster Perseus A, a huge galaxy that is blasting out X-rays. In this image by the orbiting Chandra X-ray Observatory, the galaxy is between the two "eyes", which are most likely gigantic bubbles of gas expanding away from the supermassive black hole at the heart of the galaxy. Those dark regions are each half the size of our own Milky Way galaxy, 100,000 light years across!
A rose, by any other name, would smell ... like rotting corpses. Ewwww. (And yes, it's a real picture!)
The knee of Orion is marked by the bright star Rigel, and just off to the side is the large glowing Witch Head nebula, which really does look like a classic depiction of a hag's face: open-mouth, scraggly nose, deep eyes, gaping as she looks off to the right.
This image was taken by astrophotographer Rogelio Andreo, and was a small piece of a vast Orion mosaic he made. It was so incredibly beautiful that I picked it as my No. 1 astronomy picture of 2010.
What scares a ghost? Something must have frightened this poor guy, since he's running for his ... uh. .. life? Death? Whatever.
This is one of my favorite nebulae in the sky, and if it looks familiar, it should: In a bizarre—and literal—twist of fate, it's actually the picture of the Witch Head Nebula turned sideways!
I love that you can take an astronomical picture related to Halloween, turn it 90 degrees, and get a different Halloween picture! Turn your head to the left to see the Witch.
If you have a hard time seeing it, the ghost is running to the right; the upswept arc on the right is his arm (the Witch's chin), his head is the bump to the left (the Witch's lip), his other arm is the arc on the left (the Witch's nose), and his ghostly feet dangle below.
Adam Block is a fantastic astrophotographer, using the 0.8 meter Schumann telescope in Arizona to take incredible images. This one shows gas and dust around the very young star V633 Cas, still in the throes of birth. When human babies are born, they scream, and from the looks of this star it is, too. But oits age is estimated as more than 30,000 years, which is a long, long time to wail ...
This is a small part of a much larger and fantastically beautiful image of the region around the nebula vdB1, and I really recommend you take a look. It's breath-taking.
160,000 light years from home, the Tarantula nebula (how's that for a Halloweeny name?) is a factory cranking out thousands of stars. Some of these stars are so luminous they have heated the gas to millions of degrees, and this expanding hot gas (in blue) has pushed open bubbles in the cooler gas around them (red).
And if that were happening inside of you, I imagine you'd be screaming in fury as well.
Man, that is one ticked off nebula. I'm glad it's so far away.
In 2012, my wife and I hosted a group of science enthusiasts to a vacation at the C Lazy U dude ranch as part of Science Getaways—vacations with extra bonus science added. While out on our biology hike, we saw vast groves of aspen trees, and learned that they reproduce themselves by sending up runners from their rooots—clones, essentially.
One, though, must've suffered an error during the DNA transcription. Unless there's some evolutionary benefit for an aspen tree to have a bleeding eye in its trunk.
And if that's the case, I don't think I wanna know.
This seriously disturbing image is not actually a photo, and it's not actually an astronomical object! It's an image of the Eyjafjallajökull volcano in Iceland when it was erupting in 2010, made using radar observations.
But c'mon, look at it! How could I not include it?
Even in space, you can't escape Halloween! I'm not sure what it is on the right that's chasing those two poor, terrified people running away with their arms up in the air, but it must be really scary.
This is SH2-136, a Bok globule, a dark blob of gas that forms stars deep within. Parts of it are lit up by nearby stars, allowing us to witness this act of cosmic trick-or-treatery.
A vast cloud of gas surrounding two huge clusters of stars stares at you, glaring, knowing you should be working and not reading Halloween blogs.
Or is that your conscience speaking? This is actually a star-forming cloud called NGC 2467, as seen by the MPG/ESO telescope in Chile. Each eye is actually a cluster of stars, blowing huge holes in the gas cloud, forming what looks like two colorful eyes burning a hole into your very soul.
I have to note: this object is in the constellation of Puppis, the stern of a cosmic ship. So this really is a stern glare!
Glowing ominously green and yellow in this picture, the nebula W5—nicknamed (seriously) the Soul Nebula—peers into your soul with its black eye sockets filled with pinprick stars ...
But really it's a vast cloud of gas furiously churning out stars. The winds of subatomic particles and fierce light from those newborn stars carve out cavities in the gas, leaving what look like eye sockets and a nasal bone in a huge green skull.
I have to say ... it looks a lot like the very creepy aliens called “The Silence” from Doctor Who.
This image was taken by astronomer César Cantú, who has dozens of other stunning astronomical photos on his site ... but none quite so creepy.
At the center of our Milky Way galaxy lurks a massive black hole, which, for the moment, is quiet. The surrounding material barely glows in radio waves, but there, off to the right ... is that the baleful face of a woman, just a half a light year from the monster? Why is she sad? What is she mourning?
Perhaps she perceives her own fate: being twisted around, the gas making up her visage warped and wrapped as it circles that black hole over thousands of years, eventually, it may be, to take the final plunge into eterity.
OK, I made that name up. It's actually called DR 6, which isn't nearly as much fun, especially at this time of year.
This is an infrared Spitzer Space Telescope image of the gas cloud, which is forming a dozen or so stars inside it. The eyes and mouth are bubbles in the gas blown by the winds of the newborn stars.
So in a way, it really is yelling. But at a distance of 4,000 light years—and across the vacuum of space—there's nothing we can hear.
Except: BOO!
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If Global Warming Is a Hoax…
If global warming is a hoax...
… then why was this September globally the hottest September on record by a substantial margin?
… then why were seven of the months in 2015 (so far!) the hottest of those months on record (February the hottest February on record, and so on)?
… then why is 2015 on track to be by far the hottest year on record?
… then why was the last warmest year on record just last year?
… then why are the ten hottest years all since 1998?
… then why are we seeing far more high temperature records broken than lows?
… then why did summertime arctic ice thin by more than 80 percent from 1975 to 2012?
… then why is arctic sea ice volume dropping so fast it’s called a “death spiral”?
… then why is the percentage of older ice in the arctic dropping?
… then why are we losing 450 billion tons of land ice every year?
… then why have we lost 5 trillions tons of land ice just since 2002?
… then why are Earth’s sea levels rising by more than 3 mm per year?
… then why are the oceans getting more acidic?
… then why are the vast majority of glaciers across the planet melting?
… then why do at least 97 percent, and perhaps as high as 99.9 percent of climate scientists say it’s real?
… then why don’t climate change deniers publish papers?
… then why do global warming deniers keep using long-falsified claims?
… then why does every conservative political party in the world except the GOP think it’s real?
… then why has the fossil fuel industry dumped more than $36 million (so far!) into the 2016 elections, with a staggering 93 percent of it going to Republicans?
… then why the hell is our globe warming?
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New Concepts to Explore the Jovian System
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ISS Daily Summary Report – 10/27/15
October 28, 2015 at 12:53AM
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2015年10月27日 星期二
Bright from the Heart Nebula
NASA Webcasts/Telecons on Wednesday
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Selecting Landing Sites For NASA's Journey To Nowhere
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More NASA History Destroyed in Alabama
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Indonesia Fires Seen From a Million Miles Away
Normally, I think pictures of Earth from space are among the most beautiful of all astronomical photos. Our home is gorgeous, especially when seen from afar.
But Monday, NASA tweeted a picture of our world whose ugliness made me literally gasp when I understood what I was seeing.
The photo above is from the Earth-observing DSCOVR satellite, which sits 1.5 million km (almost a million miles) over our planet, taking full-disk images every hour, which are then put online for the public to view. That shot was taken on Oct. 25 at 05:37 UTC. NASA put the picture on Twitter to point out the three tropical low systems developing in the Indian Ocean. Which is great, and very cool. But what caught my eye was the huge grayish hazy patch over Indonesia, over to the right a bit.
It took me a moment to figure it out, but then it hit me: That’s smoke from the Indonesian peat bog fires that are raging out of control right now. Fires in these peatlands have been going off and on for years, but 2015 is on track to be the second largest on record (after 1997). There have been nearly 100,000 active fires recorded there in this year alone.
These fires are dumping vast amounts of carbon into the atmosphere in the form of carbon dioxide and methane. According to GlobalFireData.org, the fires this year have tripled Indonesia’s CO2 output, emitting as much as the entire country of Japan did in 2013.
On Monday, President Obama met with Indonesian President Joko Widodo, and they talked about these fires.* Indonesia is the fifth largest greenhouse gas emitter in the world, and these fires aren’t helping. Worse, many of these fires are set purposefully to clear for agriculture, but the El Niño has worsened them significantly.
The total amount emitted from these fires just this year is well over a gigaton, a billion tons, of CO2. Globally, humans put out about 40 gigatons of CO2 per year, so this is a staggering amount.
As your eyes can show you. These fires can literally be seen from a million miles away.
*Correction, Oct. 27, 2015: This post originally misspelled Indonesian President Joko Widodo’s last name.
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Where Should Humans Land on Mars? Workshop to Discuss Possibilities
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A Snowball’s Chance in Paris
Hot on the heels of finding out the Chair of the House Science Committee is amplifying his climate science denial to 11 comes the news that his counterpart in the Senate, James Inhofe (R-Oklahoma), has a dial that goes to 12.
Inhofe, you see, may travel to Paris in December specifically so that he can disrupt progress at an international climate conference.
Inhofe, you may remember (to your brain’s infinite regret) is the climate-change-denyingist of all climate change deniers. The apex (or nadir, really) of his career came in March 2015 when he — and it makes my synapses ache even to write this — brought a snowball on the floor of the Senate, claiming that it disproved global warming.
Yes, seriously.
This idea is ridiculous (the Earth’s axis is still tipped, folks, so we still have winter), but par for the course for the man who literally wrote the book on denying reality. He’ll do or say anything to downplay or reject anything to do with global warming.
You may be shocked to learn that oil and gas companies donated nearly half a million dollars to his campaigns from 2011 – 2016.
The Paris conference in question is part of the United Nations Framework Convention on Climate Change, an important group consisting of 195 countries that have signed on to reduce “‘dangerous’ human interference with the climate system”. President Obama is hoping to get a multi-country climate deal put into place at the Paris summit. My own expectations of this are low, since these summits haven’t had a huge success rate.
But I think it’s better to try to have these meetings and be honest about the situation. Having Inhofe there won’t help, unless he’s planning on wearing a big red nose and shoes.
The Hill quotes him as saying:
I don’t know if I’ll repeat what I’ve done several times before, which is to go over and be the bad guy, the one-man truth squad, and tell the truth, that they’re going to be lied to by the Obama administration.
What could possibly go wrong with someone like him at the summit? Except, of course, making the Unites States look even more foolish on a global stage.
It’s too bad Inhofe doesn’t listen to some of his other party members in Congress, like Carlos Curbelo (R-Florida), who wants the GOP to focus more on climate change and work on incentives for alternative energy sources, and Kelly Ayotte (R-New Hampshire), who signed on with Obama and the EPA’s Clean Power Plan, which targets power plants to reduce carbon emission. I may quibble with both of these folks on specifics, but at least they’re facing the right way. Their heads are out of the sand, and that’s a breath of fresh air from the GOP on this issue.
Tip o’ the snow cone to Allan Margolin.
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Scott Kelly Prepares For a Spacewalk
ISS Daily Summary Report – 10/26/15
October 27, 2015 at 12:57AM
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A Piece of Cosmic Debris Will Hit Earth on Nov. 13... But a) We're Safe, and 2) It's One of Ours
[Before I even start, I know some people get very nervous about stories like this. Let me assure you, were safe. Read on, and don’t panic!]
For one of the very few times in history, humans have spotted a piece of cosmic debris on an impact course with Earth before it enters our atmosphere and burns up.
The object, temporarily called WT1190F, will enter Earth’s atmosphere and burn up on Nov. 13 around 06:20 UTC (01:20 Eastern US time) near Sri Lanka. And it almost certainly will disintegrate harmlessly in our air; it’s too small and light to reach the ground. We've seen objects coming in from space that have hit us before — specifically the tiny asteroids 2008 TC3 and 2014 AA — but this time astronomers are pretty sure it’s not an asteroid at all, but actually a rocket booster or fuel tank from a previous launch!*
WT1190F was discovered on Oct. 3, 2015, just a few weeks ago, by astronomer Rose Matheny in data taken by the Catalina Sky Survey. It’s very unusual. For one thing it’s very faint, and therefore quite small, and for another it’s in orbit around the Earth! Right away this makes it overwhelmingly unlikely to be an actual asteroid; an asteroid on an impact trajectory with Earth will almost always be coming from deep space.
It orbits the Earth on an extremely elliptical path, which is also typical for used-up rocket motors. It orbits once every three weeks or so, getting as far away as about 650,000 km (more than 1.5 times as far as the Moon). Again, this is far more like a rocket booster than a natural asteroid. Given that orbit, it may very well be from a recent Moon mission.
According to the European Space Agency’s Near-Earth Asteroid group, it was also seen in Catalina data from 2013, allowing a pretty good orbit determination (the longer you observe an object, the better you can figure out its orbit). Over time, the orbits of objects can change due to a number of factors, including (seriously) pressure from sunlight. By measuring this effect, astronomers have calculated that WT1190F has an incredibly low density, about 10 percent that of water. No known asteroid has a density this low, but it makes perfect sense if it’s a hollow object like a booster or fuel tank, probably just a couple of meters across.
This is why we can be confident it’ll burn up harmlessly. Its low density and small size means it’ll slow very rapidly once it contacts Earth’s atmosphere, creating a lot of heat that should break it up and vaporize it. I’ll be careful and say that some pieces may survive re-entry and hit the Earth’s surface, but they’re likely to be very small.
Note that the impact is expected to occur about 100 km off the southern tip of Sri Lanka over the Indian Ocean (since the Earth’s surface is 3/4 water, most impacts occur over the ocean). That prediction may be off by 10 – 20 km or so (atmospheric drag makes pinpoint precision impossible with such objects re-entering), but still, it seems very likely that any pieces that manage to survive will fall into the water.
It’ll be very faint right up until it burns up, far fainter than a human eye can see (if you’re an astronomer who wants to try your hand at observing it, the ephemerides are online by Bill Gray of Project Pluto; also note the ESA NEO Coordination Centre will be putting together an observing campaign, so head over there and take a look at their site). Once it enters Earth’s atmosphere though it’ll rapidly heat up, glow, and should put on quite a show for people in the area. I hope we get good photos and video! If you live in Sri Lanka and catch it, please contact me!
If you are in that area, you’ll need clear skies above you and to the south to see it. When it happens, it’ll be moving faster than a satellite would across the sky, but slower than a typical meteor, and may actually look like it’s shedding sparks as bits and pieces of it melt off and blow away.
To be clear, I’m not at all worried about this, and in fact I’m quite excited we may get a chance to see it! It’s very rare to find an object before it impacts, and in the previous two cases they were discovered only about a single day before they burned up.
This time we have a few weeks, so hopefully there will be more observations of it. That’s important: An object under the influence of non-gravitational forces (like sunlight pressure) can have a difficult orbit to predict, so the more observations of it we have, the better we’ll understand just how these forces work on small objects.
This will also be a nice shakedown of the systems in place that alert us to any more dangerous incoming objects. Testing those out under safe circumstances like these strikes me as a pretty good idea, too.
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NASA Administrator to Discuss Agency’s Journey to Mars at Center for American Progress
October 27, 2015
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2015年10月26日 星期一
Charon and the Small Moons of Pluto
NASA Is In The China Hot Seat Again - Twice
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Making More Orions
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Human spaceflight
As is often the case, the United States chooses a different definition to the rest of the world. The US prefers to use 50 miles (~80km). The practical difference from using the lower altitude is that six US Air Force pilots are then included as astronauts. I stick to 100km as it has some kind of physical justification.
Using a 100 km definition of space, there have been 545 astronauts so far but expect that to increase by December 2015 when the next Soyuz goes up to the ISS. These split into 331 from the US (NASA), 120 Russians, 10 Chinese, 9 space tourists, and 75 from a range of other countries.
For my recent book, I collated data on all 545 astronauts and made visualisations of various aspects. On the website, I've created a human spaceflight timeline which lets you see when every mission was along with key moments.
There are a few things that become obvious when it is presented like this. The first is how we've increased the duration of spaceflights over the years. You can see how short the Shuttle missions were (roughly 8-12 days long) compared to those on space stations such as Mir or the ISS. It is also easy to see the pauses in the human spaceflight programmes of the Soviets and the Americans following the disasters of Soyuz 11, Challenger, and Columbia.
I've also created a graph of astronaut data, a map of astronaut birthplaces, a page which shows who is in space and who was in space (just change the date in the URL), and a breakdown of astronaut stats and records. - taken from Astronomy Blog (http://ift.tt/1g8FhhM)
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NASA Seeks Student Experiments for Edge-of-Space Balloon Flight
October 26, 2015
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Pluto’s Tiny Dumbbell Moon and a New Target for New Horizons
A new image from the New Horizons spacecraft finally completes the entire Pluto family portrait, showing Pluto’s smallest (known) moon, Kerberos.
And surprise! It’s double-lobed!
That’s actually only mildly surprising; a lot of small asteroids and comets are not single, lumpy objects, but are instead shaped like bowling pins (or dumbbells, or dog bones). Something like 10 – 15 percent of all near-Earth asteroids are double-lobed (we have decent statistics on that particular group because they get close enough that we can measure their shape using radar).
These objects probably form from slow speed collisions between two small objects; they graze each other, slow, then merge to form a single, if stretched out, object. New studies of the comet 67P Churyumov-Gerasimenko show it almost certainly got its rubber ducky shape the same way.
The current thinking is that Pluto’s moons formed after a huge collision splashed vast amounts of material into space, which then coalesced into the moons we see now. Most went into Charon, but the leftover debris formed the smaller ones. In that case, slower speed collisions between objects forming from that material would have been pretty easy, so in fact it seems 50/50 that one of those smaller moons would be double-lobed. Looks like we got lucky.
Kerberos has another surprise, too: It’s smaller and brighter than expected. Previous Hubble observations indicated it was probably big due to its influence on the moons, and therefore dark. Instead, it’s small and shiny. The whole thing is about 12 km end to end, with lobes eight and five kilometers across (making it roughly three times bigger than the comet 67P). It’s likely covered in water ice, like the other Pluto moons, which is why it’s reflective. Why this contradicts the previous Hubble observations is a mystery.
The picture at the top has been heavily processed and enlarged to bring out details; each pixel is about 120 meters across, about the size of an American football stadium.
What’s funny to me is that this moon is named after Cerberus, the three-headed dog that guarded the underworld (the actual name “Cerberus” was already used for an asteroid, hence the odd spelling for Pluto’s moon). In reality, Kerberos only has two heads! So much for ancient myths.
But we’re not quite done yet.
New Horizons passed Pluto on July 15, 2015, still moving at about 14 km/sec relative to the icy world. So it’s still going! And astronomers aren’t ones to waste opportunities: Beyond Pluto lies the Kuiper Belt, a flattish donut-shaped region with millions of small, icy bodies. We’ve found over a thousand of them, but never seen one up close. Why not see if any are near New Horizons’ path?
Using Hubble, last year astronomers found a potential target for the probe. 2014 MU69 was chosen. It lies well over 1.5 billion km past Pluto, and its size is unclear (it depends on how dark it is; if its darker it’s bigger, shinier and it’s smaller) but probably in the 30 km range.
The cool news: On Thursday engineers on Earth commanded New Horizons to fire up its engines to swing its trajectory to pass MU69! AmericaSpace has details; it’ll take a total of four such burns to point New Horizons the right way.
I’ll note that this is the farthest course correction ever made from Earth. The probe is currently just over five billion kilometers from Earth. Wow.
New Horizons will pass MU69 in January 2019 — yes, over three years from now. Space is pretty big, and 1.5 billion km is a long, long way. But still, we’re threading the needle: The hope is to pass less than about 12,000 km from MU69, close enough to get decent details on its surface (and see if it has any small moons itself). If they pull it off, it will be the most distant close encounter in history.
If they are allowed to pull it off, I’ll add. This part of the mission hasn’t been approved by NASA yet. The New Horizons team will send a proposal to NASA for funding it in early 2016, and should know later that year if it’s approved. I know it’s weird to start the maneuvers before you know if you can actually do the mission, but in this case orbital mechanics overrules NASA bureaucracy; they had to do the burn now, or else they wouldn’t have enough fuel to do it later.
I suspect NASA will approve the follow-up. The Pluto encounter was huge news; people loved it, and the science from it was and continues to be amazing. The additional expense of taking a peek at MU69 is small compared to that, and the payoff potentially big. Seeing a Kuiper Belt object up close would be a huge bonanza for astronomers. These icy chunks are leftover from the formation of the solar system, and likely preserve a lot of information from that time, over 4.5 billion years ago. Chance like this don’t come often. I think we’ll take it.
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Space Station Crew Celebrates 15 Years of Human Space Exploration in Low-Earth Orbit
October 26, 2015
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A Tale of Two Hemispheres
GOP Congressperson Goes on a Climate Science Fishing Expedition
Congressperson Lamar Smith (R-Texas) is a flat-out 100% global warming denier. He has made that very clear, writing embarrassingly wrong op-eds for the Wall Street Journal, and engaging in Orwellian claims about climate science and politics. It’s clear he’s not a huge fan of politically-independent science in general; for example he wants to gut peer-review in the National Science Foundation’s choices on what research to fund (instead, only allowing those that are politically approved).
The current crop of GOP Congresspeople is maniacally fixated on stopping any science that doesn’t march along with their ideology, and will do almost anything to stop it.
That’s why I am not at all surprised that Smith — who is the Chair of the House Committee on Science, Space, and Technology, mind you — would go on a fishing expedition. He subpoenaed Kathryn Sullivan, the Administrator of the National Oceanic and Atmospheric Administration, asking for a sweeping amount of information, including all documents and communications from NOAA employees about how they use global temperature datasets, including satellite data, and more.
This subpoena smells a lot more like politically motivated strong-arm tactics than an actual attempt at oversight. Eddie Bernice Johnson (D-Texas) thinks so, too, which is why she sent a scathing letter to Smith, accusing him of using his power as Chair to “harass and second guess our nation’s preeminent research scientists,” and that he’s creating a “baseless conflict.”
She further questions the ability of him or his staff to properly analyze the data he’s asking the NOAA for, saying, “There’s certainly not enough scientific expertise on your staff or on the Member rolls to reanalyze the scientific data you have been provided.”
Ouch. She’s right. It’s clear that Smith doesn’t understand, willfully or otherwise, even the most basic ideas about global warming; he still claims global temperatures haven’t risen since 1998, for example, sticking to a “pause” in warming that we know, and have known for some time, doesn’t exist.
It sounds far more like Smith is doing whatever he can to unearth anything global warming deniers can use to sow more doubt. It reminds me strongly of “Climategate”, when climate scientists’ emails were stolen, then taken hugely out of context by deniers to make it sounds like they were up to nefarious purposes. That whole thing wound up being total baloney, and the scientists involved were completely exonerated of wrongdoing. Multiple times.
Smith’s abuse of power can be seen in other ways, too. Recently, a scientist named Jagadish Shukla penned a letter to the White House asking that fossil fuel companies be investigated under antiracketeering laws for funding disinformation campaigns about global warming (a campaign we know they did and have continued to do).
Smith’s response? He has called for an investigation into a nonprofit energy research group headed by Shukla. Seriously. Huh.
I’m sure it’s a coincidence that oil and gas companies have given well over $600k in donations to Smith’s election campaigns over the years.
This sort of political threatening is appalling, and harkens back to the days of Joseph McCarthy.
And, to be honest, I personally think it’s worse than that. We have an entire faction of Congress that rejects science and wants to substitute it with its own version. This idea has been tried. In the 20th century, the Soviet Union embraced the crackpot biological ideas of Trofim Lysenko, who rejected the idea of evolution by natural selection. They and other countries based their agricultural system on this pseudoscience, and the results were devastating. Lysenkoism led in part to worsening the Great Chinese Famine, where 30 million people died.
The parallels here are striking. We have an overwhelming consensus of climatologists all over the world agreeing that the planet is warming up and that humans are at fault, while a small but powerful group of politicians, ideologically motivated, are working to suppress that science and replace it with nonsense. The consequences are not minor and relegated to some distant, fuzzy future; they are now and they are global.
I am not a single issue voter, not by a long shot. But science isn’t a single issue. Its implications cover global warming, health care (especially women's health care), space exploration, personal privacy, technology, immigration (for example, the engineering of building a border wall), job creation, and much, much more. All of these are major issues in the upcoming election.
Your vote counts. These politicians thrive on apathy, and their biggest fear is a population that actually turns up to vote. We cannot allow these few zealots to continue this attack on science and reality. It’s long past time we showed them the door.
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