Bad Astronomy
You know how we know there&s a giant peanut in the center of our galaxy? Because X marks the spot.
That was a fun thing to write. It also has the advantage of being true.
Artwork depicting the Milky Way seen face on. The bulge is the yelow-red ellipse in the middle.
NASA/JPL-Caltech/ESO/R. Hurt
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, with a broad disk 100,000 light-years across filled with gas, dust, and stars. In the center is a bulge of older stars, which was once thought to be more or less spherical. In more recent times it&s understood to be what&s called a &bar,& an elongated shape more like a Tic Tac.
Barred disk galaxies are pretty common. When we see an external galaxy face-on the elongated bar is usually pretty obvious. When we see them edge-on, though, it&s harder to distinguish from a spherical bulge.
We&re inside the disk of the Milky Way, so we see our galaxy edge-on. That&s made the central bar difficult to study in detail. Plus, all that gas and dust in the way is a pain, blocking our view.
NASA&s Wide-field Infrared Survey Explorer, or
detects infrared light, which can get through that dust, so we can see the stars in the center of the galaxy more clearly. In a new study, astronomers found that the stars mark a huge X centered smack dab in the galactic core. That&s the image at the top of this article.
Artwork depicting the double-lobed peanut-shaped Milky Way star bulge.
ESO/NASA/JPL-Caltech/M. Kornmesser/R. Hurt
So, what the what? What&s this giant X doing there? A big clue can be found . This revealed the stars in the galactic core are arranged in a peanut shape, a two-lobed cloud with a thick neck between them. If you were above the Milky Way, looking down, that peanut shape would just look more or less like an elongated bar, but from the side the peanut is more obvious.
Plots showing various possible banana-shaped orbits of stars seen edge-on. 1 kpc = 1 kiloparsec = 3,260 light-years.
Portail, Wegg, and Gerhard
It turns out the stars in that part of the galaxy don&t just orbit the center in circles like planets around the Sun. Instead, the overall gravity of the other stars in the bulge distort their orbits into weird shapes. Seen from the side, , or move up and down in complex patterns. Stars distributed all along these orbits trace out the peanut shape.
So why the X? That&s because the peanut is made of stars, and so it&s &transparent&; we can see stars all through it. When we look near the edges of the peanut we see more stars than when we look through the middle (an effect very similar to ). That&s what forms the X. Think of the edges of the cones form an X. It&s the same sort of thing in the galaxy.
But there&s more! It&s hard to tell, but the two arms of the X are actually bigger on the left than on the right (this can be seen better in Figure 1 ). That&s because that side of the peanut is closer to us! The center of the galaxy is about 26,000 light-years away, and the peanut is about 14,000 light-years long. Not only that, but it&s rotate we see it nearly along the long axis but spun around by about 27&. That means the near side of the peanut is more than 10,000 light-years closer to us than the other side, making it look bigger. It&s pretty rare that we see such big structures close enough to us that perspective makes a difference in their size!
This has implications for the evolution of our galaxy. This structure is not terribly robust and would fall apart if we merged wit this means the Milky Way hasn&t suffered a large collision for many billions of years (, but those are far more gentle events&for us at least, not so much for the cannibalized galaxies). The dynamics of the stars in the bar also give clues to how they formed, and how they&ve evolved over the eons, too.
This is all pretty neat and shows that there&s still a lot we have to learn about our own neighborhood, cosmically speaking. A lot of this research depended on having the rig specifically infrared telescopes to pierce the dust and powerful computers to calculate the very complicated orbits of the stars in the peanut.
Not only that but another advance that was critical to all this was & Twitter. Yes, seriously. One of the people working on this, Dustin Lang, created a website with the WISE images on it. , and it caught the notice of astronomer , who saw the X shape and realized what it meant, leading to their collaboration.
Social media indeed.
Astronomers are pretty good at rolling with the times. New tech and new techniques are part of the job. And when used wisely (har har) they can lead to some pretty beautiful insight into the Universe.
Quick: Name a female scientist.
Can you think of one? Folks reading my blog are probably more bent toward science, so I suspect the odds are better than if you ask that same question of the public. , many times, and most people come up with Marie Curie. If you ask them to name a living female scientist, they come up empty.
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That needs to change. Women have made a huge contribution to science, and the way we marginalize them is atrocious.
That&s why MIT news editor and science writer
proposed the creation of . The set would feature notable women: , , , , and , all of whom had critical roles at NASA.
Minifigs like this are very popular, and could be a great gift for boys and girls. And it would raise awareness of these important role models in NASA hi .
This se it&s been proposed and needs 10,000 supporters to go to
of being officially reviewed at Lego HQ. So sign up (it&s free) and . It would be great to see this set get into the hands of thousands of kids (and, I&d wager, not a few adults) across the world.
Thanks to my friend Bonnie Burton for letting me know about this. , too!
Do you like wine, gigantic trees, telescopes, and science?
Then do I have a vacation for you: Science Getaways is going to California wine country!
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Science Getaways is a company run by my wife, Marcella, and me, where we take vacations you&d want to go on anyway and add science. We&ve done these in Tucson, Arizona (space!), Oregon (volcanoes!), Hawaii (more volcanoes!), and more. We lived in Sonoma County for many years before moving to Colorado, and it occurred to Marcella that there&s a lot of science in growing grapes, making the wine, and even in bottling and drinking it. So why not?
Seriously. We'll be eating here on Halloween.
Deerfield Ranch Winery
We&re calling this one . It&ll be from Oct. 31 to Nov. 4. We&ll be visiting several wineries in both Sonoma and Napa counties, talking to oenologists (scientists who study wine), and sampling their wares. Given the date, we&re starting off with a spooky Halloween cave dinner at
in Kenwood (yes, they store their wine in a cave, and it&s delicious).
We&ll also be visiting what is no fooling one of my favorite places on Earth: The giant redwood forest of . This is a profoundly moving and beautiful place, with trees towering more than 100 meters high.
We&ll wrap up the trip with a private night at , where I&ll give a brief talk on some select astronomical objects and then, weather permitting, you&ll see them for yourself through their telescopes, including their brand-new one-meter telescope! I&m really looking forward to that.
If this sounds like the vacation for you&and you&re 21 or over, of course&then check out the
and register. We&re actually down to just a few more slots, so book it while you can.
See you in California!
P.S. There&s still room for
on Sept. 19-23 too, assuming the idea of a week in Hawaii doing sciencey things appeals to you as well.
On Wednesday night, at around 9:30 p.m. Pacific time, a huge fireball lit up the sky from California to Utah. Moving eerily slowly, bits of it were seen to fall off like sparks as it made its way across the sky.
Twitter lit up like the fireball itself at the time, and I was flooded with replies and queries.
had one of the best videos of the event, taken by Matt Holt in Utah. Watch this:
Full video of meteor-like event
& Matt Holt (@mholt6)
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As soon as I saw this I knew it wasn& that is, not a piece of asteroidal rock or metal coming in from deep space. Those move much more quickly across the sky, and tend not to break up with pieces following it like that.
Clearly, this was human-made space junk. Orbital speeds are much slower than interplanetary speeds (eight kilometers per second for low Earth orbit versus 20 up to 100 kps for meteors). Remember the end of the movie , when Sandra Bullock comes back to Earth in a Chinese re-entry vehicle, and you see bits of it streaming around her as it burns up? Yeah. Pretty much that.
Not too long after the event the piece of space junk was identified: It was a booster from a , which re-entered at 04:36 UTC (thanks to my friend and space junk junkie
for that info), moving roughly . It launched on .
, taken by Ian Norman in Alabama Hills, California, in the Sierra Nevadas not too far from the Nevada border (note: some NSFW language):
Pretty amazing. Another person there with Norman .
happened to be shooting near Mono Lake in California and captured it as well as it set over the hills:
A long exposure of the re-entry shows the Milky Way in the background.
Jeff Sullivan, used by permission
Apparently it was spotted as far east as Colorado, which means if I had been outside, I might have seen it, but there&s also a big wildfire a hundred km or so to my northwest that&s covered the sky in smoke, so it&s hard to say if I&d have seen it or not. Oh well.
So, bottom line is that this wasn&t a meteor, it&s not the end of the world, or aliens, or anything like that. I mean, ho-hum, it was just a piece of human-made technology, designed to take objects from the surface of our planet into space, coming back down at 20,000 kilometers per hour, disintegrating and burning up as it rammed through the air 100 km up at transonic speeds.
Y&know, boring stuff like that.
Three hundred eighty light-years from Earth lies a very bizarre binary star.
Called AR Scorpii (or AR Sco for short), it&s been known for decades but was masquerading as a relatively humdrum variable, a single star that changes its brightness due to pulsations, literally an expansion and contraction of its size.
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But there was something odd about it. Instead of a nice, smooth brightening and dimming, a team of astronomers noticed that it has a lot of scatter in its brightness, a lot of apparently random noise on top of the smooth variations. Not only that, but the noise was only apparent in one part of the cycle, which didn&t make sense.
. And what they found is that AR Sco is not a simple star at all. It&s a , with one of the stars being the corpse of a normal star. And not only that, the corpse is feisty, and well-armed: It&s zapping the other star with the stellar equivalent of a death ray.
Man, I love .
Here&s the deal. AR Sco is two stars orbiting each other. One, the brighter of the two, is a
with less than half the mass of the Sun. These stars are generally pretty faint and cool.
When the astronomers took a spectrum of the star, they got some surprises. A spectrum is when you break the light up into individual colors, sometimes thousands of them. . The first interesting bit is that the red dwarf has a lovely, smooth Doppler shift in its spectrum, which means that it&s in orbit around another star. The period of that orbit is just 3.56 hours.
Next, no hint of light from that other star is found. That means it&s very faint. It also has a heckuva gravitational pull, if it can toss around another star in an orbit that&s just a bit longer than the length of a typical Marvel movie.
Also, the red dwarf spectrum is lousy with . These are bright lines in the spectrum usually associated with fairly hot material, and you don&t usually see them with red dwarfs. These are booming out, though, which is consistent with a very hot nearby source of energy.
That strongly points to the other star being a
or a . The first is the core of a star like the Sun after its &normal& life has ended, and it&s blown off all its outer layers. The remaining object is small, about the size of the Earth, but can have from half to about 1.4 times the mass of the entire Sun squeezed down in it!
A neutron star is the core of a more massive star that exploded. It&s even smaller and more massive than a white dwarf. Both are very hot, and could heat the side of the red dwarf facing them, causing it to have emission lines.
Figuring out which one of these two bizarre objects is the key to understanding this system. Happily, there&s more data! And this one&s a doozy.
The entire system pulses in brightness on a very short timescale. The visible light (the kind we see) increases by a factor of 20 times every two minutes. Similar pulses are seen in ultraviolet, infrared, and radio light as well!
The kicker: No X-rays are seen from the system at all. So what does all this mean?
The most likely culprit is that the unseen star is a white dwarf. The pulse period of two minutes is consistent with the spin of a white dwarf, but neutron stars tend to spin much faster. Also, the only way for a neutron star to heat the red dwarf would be for it to be drawing material off the dwarf, which would impact the neutron star and glow. If that were the case, this system would be blasting off X-rays, but none are seen.
So it&s a spinning white dwarf. The fact that we see light emitted from the system across all wavelengths is a pretty strong piece of evidence that it&s coming from what&s called : Light emitted by electrons in a very strong magnetic field. That&s consistent with a white dwarf as well, which are known to be pretty strong magnetically.
And now we have all the pieces to the puzzle. The red dwarf is orbiting the white dwarf. The white dwarf&s magnetic field is accelerating electrons up to very nearly the speed of light, and likely emitting them in a beam, like a lighthouse. This whips around the star every two minutes as it spins, and when it passes over the red dwarf it heats the side of the red dwarf facing the white dwarf. When this happens the system blasts out light at much higher rates.
Near-infrared observations (top) show the brightening/dimming overlaid with lots of scatter in some parts. Measurements of the red dwarf's velocity (bottom) show its speed toward (negative values) and away (positive values) from the Earth. The plot repeats to make it easier to see how the features cycle. The scatter in the top plot happens when the star is moving away from us, heading to the other side of its orbit, so we see the side lit by the white dwarf.
Marsh, et al.
Remember the odd scatter in the light from the red dwarf that started this whole investigation? What we&re seeing there is the inflamed side of the red dwarf facing the white dwarf, the part under the withering blast of the electron beam*! We only see this part of the star when it&s facing us, when the red dwarf is on the other side of the white dwarf (it&s like the phases of the Moon that way). When we see the &back& side of the red dwarf, things look normal. But when the hot part slides into view as the red dwarf circles around the white dwarf, the light we see gets brighter overall but also fluctuates wildly as the star gets zapped by the electron beam.
Yeah, I know. This system is weird. In fact, we&ve never seen anything quite like it. Other binaries with a red and white dwarf don&t behave this way, so we have something special here. And the cool news is it&s fairly close, so we can study it more easily.
And the part that leaves me smiling about all this? This truly peculiar star has been sitting there in our back yard all this time, and astronomers only took a closer look because they saw something odd in the light it was giving off. When they looked closer, they found all sorts of lovely treasures.
What else is out there we haven&t stumbled on yet?
* There is another possibility: The red dwarf is plowing through the white dwarf&s magnetic field, and that&s what&s causing the glow. But that doesn&t explain the two-minute pulse period, so I&m leaning toward the electron death ray hypothesis.
Ceres is the largest object in the asteroid belt, a world more than 900 kilometers in diameter. It&s so big that planetary scientists tend to refer to it as a protoplanet rather than an asteroid. The latter group consists of pulverized rubble left over from the planetary formation process billions of years ago, but Ceres is different. It got big enough that it was well on its way to being a planet before it ran out of material to build with.
When we look at objects in the asteroid belt (and many moons of large planets), we see them covered in craters. Saturated, actually, with so many craters that a new impactor is likely to erase a few older ones when it hits.
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The smaller the crater, the more of them there are. T there are only a few objects big enough to create really big craters, but gazillions of smaller ones that can make smaller craters.
Still, pretty much every object we look at has a handful of really monster impact craters, some approaching the diameter of the object itself&remember, a crater will follow the curv Vesta, smaller than Ceres at 525 km across, has a crater 500 km across on it. That crater stretches over about a third (well, about 1/pi) of the surface.
So we expect to see a few very large craters on every object we study.
& except with Ceres we don&t. For some reason, .
The Dawn mission has been orbiting Ceres since March 2015,
(as well as lots of other data). Using these images, . The biggest craters, named Keran and Yalode, are 280 and 270 km in size. That&s big, but Ceres is 940 km across. Where are the big craters?
And it&s not j the numbers start to drop off at craters wider than about 100 km in diameter. It&s weird, and that&s not just intuition. The numbers and sizes of craters can be predicted using impact models based on the numbers and sizes of asteroids in the main belt. They find that there should be six or so craters bigger than 280 km, but none is found. The chance of that happening is less than one percent! They also expect roughly 40 craters bigger than 100 km, but only 16 are seen. The odds of that occurring are essentially zero.
So what&s going on?
Most likely, Ceres did have huge craters long ago, but something happened to erase them. Either lots of subsequent impacts erased the evidence, or Ceres itself did. By that I mean perhaps the composition of Ceres itself makes it such that huge craters fill in, the material surrounding the crater flowing back into it ad &patching& it.
Under the huge pressure of impact rock can flow pretty well, and Ceres also has a lot of water ice under the surface, so this idea has merit. In fact, the authors of the research indicate this is the
the process happens to big craters but not smaller ones, so it seems to be connected to Ceres itself, and not subsequent impacts.
I&ll note that there are three very large (&800 km wide) basins, or depressions, on the surface of Ceres. Those might be impact-related, but it&s difficult to be certain. The authors discuss those, and the idea that they&re so difficult to identify lends credence to the idea that something happened to resculpt them.
, looking at craters is a great way to understand what big bodies in the solar system have gone through over the eons. It helps establish a timeline of events across the solar system, and can be used to see how objects compare with one another. We already know Ceres is a bit weird&it has a mantle of briny water ice under the surface that oozes up, sublimates, and , as one example of its odd behavior&so it&s likely that if we see other unusual things going on, they&re tied together. In this case, it&s due to the internal structure of Ceres.
Ceres is a midway point between the stuff used to make planets and the planets themselves. It&s a frozen remnant straddling that line from 4.5 billion years ago, and studying it tells us more about how our own planet came to be.
Crystals are pretty. They&re also pretty interesting. They&re found in nature in stunning variety, including all kinds of bizarre shapes. I find a lot of these shapes pleasing aesthetically due to their symmetry. Some are box-shaped, some hexagonal & but they&re all fascinating.
Crystals get this symmetry because of the way atoms interact. They&re like puzzle pieces, connecting only in certain ways. For example, carbon atoms can bond to each other to form sheets that are a single atom thick, but contain zillions of carbon atoms interconnected as hexagons. We call this . But they can also connect to form tetrahedrons, four-faced triangular pyramids. The property of that crystal is very different, so we give it a different name: .
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Over the years crystallographers have found that there are four kinds of symmetries natural crystals can have: twofold, threefold, fourfold, and sixfold. These are all based on taking a shape and . For example, take an equilateral triangle. If you spin it 360& it looks the same. But it also looks the same if you spin it 120& and 240&. So after spinning it all the way around, you get the same pattern three times: a threefold symmetry.
A regular hexagon has six sides, and looks the same after you spin it 60&, 120&, 180&, 240&, 300&, and finally 360&. So it has sixfold symmetry.
Now, you could theoretically have a fivefold symmetry, for an object that goes through multiples of 72& rotations (after five of those you&re back to 360&). But that&s never found in nature. The other symmetries are very strong, and crystals find themselves displaying those instead.
& until recently. In the 1980s scientists were able to create a fivefold crystal in the lab, which they called a quasicrystal. It&s tough to do, but it can be done. Still, the big question remained: Can that be found in nature?
The answer we now know is: Yes! , and they came from the same source: a meteorite that fell in far eastern Russia called the .
. Collisions break them up into smaller pieces, and sometimes these fall to Earth. Khatyrka has an unusual composition, and when examined microscopically indeed shows signs that it had undergone collisions while it was still part of its parent asteroid body. The scientists wondered if they could replicate this. They created a series of disks made of the same minerals found in the meteorite and stacked them like coins, making something like a hockey puck. They then used a large gas gun to blast it with a projectile moving at about one kilometer per second, which is a typical (or perhaps somewhat slower) collision speed for asteroids in space.
, they found a quasicrystal with fivefold symmetry, which is now named . The chemical formula for it is Al63Cu24Fe13: 63 atoms of aluminum, 24 of copper, and 13 of iron. No wonder it&s so hard to find it in nature!
It&s not entirely clear in detail how it formed, though sudden compression, heating, and then cooling play a role. On Earth those conditions are very rare, but they&re more common in asteroids. The weird composition of the meteorite plays some part too, having the right combination of minerals to start with such that in the end the quasicrystal is created.
When examining the manufactured quasicrystal using a technique called X-Ray Diffraction, the fivefold symmetry becomes apparent. Inset: The fragment examined is attached to a thin length of carbon fiber.
Asimow et al.
At this you may be wondering, so what? I have a few whats for you. One is that nature is more clever than we are. These crystals were once thought impossible, but here they are. They&re rare, but not impossible. Just very unlikely and need very special conditions to form.
Second, this gives scientists more insight into the literal structure of nature. Perhaps quasicrystals will never have a practical application, but even if they don&t they still help us understand how the world is put together.
And third, this hints at new branches in the science of crystallography. What other crystals exist, what other strange compounds? What uses will these have? Maybe none, at least not in our ability to exploit them for technological advances, say (the way silicon was used to make computer chips as an example). But again, the more we understand the rules governing the Universe, the better we understand it, and that is a goal unto itself.
And hey, if we can figure out how to make transporters or warp drives or light sabers, then all the better. But in the meantime, just gaining knowledge is pretty cool, too.
P.S. I&ve been meaning to write about this topic for a little while, but tonight I&m giving a talk about science outreach to members of
at their meeting in Denver, so I thought the time was right.
What killed the dinosaurs?
That was a when I was a kid, there were tons of ideas but precious little evidence for any of them, making them little more than speculation. In the late 1970s and early &80s, though, the hypothesis was put forward that a giant asteroid or comet impact did the deed, and over the years evidence mounted.
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The impact idea gained wide acceptance, but some details remained stubbornly difficult to explain with a single catastrophic event. Another idea that started gaining traction was that a series of huge and sustained volcanic eruptions occurred for a couple of hundred thousand years before the impact. ; they formed the Deccan Traps, a soul-crushingly huge region in India consisting of igneous rock layers more than two kilometers deep and covering an area of 500,000 square kilometers.
Half a million square kilometers. Yeah: huge.
This long-lasting eruption did ecological damage across the planet, weakening life and killing species. The clock was ticking on the dinosaurs and so many other species. When the impact came, their time was up.
that it took both catastrophes to do in the (non-avian) dinosaurs and 75 percent of species on Earth, but
provides more support: Scientists found two warming pulses in Earth&s ocean temperatures corresponding to the times of both the volcanic eruptions and the giant impact. This suggests that large-scale global climate change effects were behind the mass extinction.
It's hard to imagine, but the creatures inhabiting these shells may have witnessed the demise of 75 percent of species on Earth.
Sierra V. Petersen
that lived around , near the tip of the peninsula sticking out from Antarctica. This is a good the island dates back to before the time of the impact (called the Cretaceous-Paleogene boundary, or K-Pg boundary&C was already used for something else, so geologists went with K) and fossils from that time are abundant on the island. The deposits layered there provide a continuous sampling from before to after the boundary with little or no jumps in time, so the record is relatively clean.
They looked at bivalves because the critters absorb minerals from the water to make their shells, and the ratios of the amounts of some minerals in the water is temperature dependent. By carefully measuring the minerals in the shells (specifically, ), the scientists can then use them as a proxy for temperature.
The plot of temperature versus time (measured in millions of years ago, or Ma) shows a long rise and fall, then a sharp uptick during the Deccan Traps eruption, another fall, then another smaller spike at the time of the impact.
Petersen et al.
What they found was a huge ~8& C (& 3&) leap in water temperature starting around 66.25 million years ago (roughly 150,000 years before the K-Pg boundary), which is when the Deccan Traps eruption started. The water started cooling again, but then there was another sharp rise of a little over a degree right at the K-Pg boundary, corresponding to the impact. That& some of the bivalve samples showed much larger spikes in temperature.
I&ll admit, the data look a little rough to me. The second pulse has pretty big uncertainty bars, so it&s hard to tell exactly how big it was. The first pulse looks quite real, though, and does support the idea that the Deccan Traps contributed to geologically sudden and biologically deadly worldwide warming.
Interestingly, there was a long, slow warming and cooling period for a couple of million years before all this. While it was a large rise (about 8&) it happened over a long period of time, so the ecological impact wasn&t as bad. A smaller rise can do far more damage if it happens quickly, .
We use the din something slow, plodding, not terribly intelligent, and in imminent danger of going extinct. This new study shows
they were ill-prepared for both sudden climate change and a giant asteroid impact.
Humans are smarter than that. We have a space program, which is us , and
are telling us very plainly that the climate of our planet is rapidly changing.
We&re not dinosaurs & if we choose not to be.
How have I never heard of
until now? It&s a little more than 100 kilometers west of Key West, Florida, in the Gulf of Mexico. It&s pretty remote, accessible only by boat or seaplane, and has an interesting history.
It&s the location of , a huge brick fortress that was constructed over a period of 30 years in the 19th century but never completed. It was built to protect the busy waters at the entrance to the Gulf and was also a prison& was sent there, convicted for conspiring with John Wilkes Booth in the assassination of Lincoln.
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It was a miserable place to be incarcerated, with terrible conditions. When I read that I that&s bizarre given how gorgeous the waters are there: crystal clear, with coral and abundant fish. Ironically, it&s a tourist destination now known for its beauty.
And it&s even more bizarre when you think about how beautiful the skies are there. With no land except a few small sandy islands all the way out to the horizon, the skies there are fiercely dark at night, and the stars shine with brilliant intensity.
I learned all this when photographer
sent me a note about his newest time-lapse video,
which is a stunning display of just how spectacular this site is:
Whoa. Mehmedinovic employed a variety of effects to enhance the scenes, including stacking frames to create
that show the motion of the stars in the sky, reflecting the Earth&s rotation on its axis. Because it&s so far south, from this location the Milky Way gets higher overhead than it does from most of the U.S. and really dominates the video when it&s visible.
I also really like the music. It's called
and was written by Terry Devine-King. .
Mehmedinovic made this as part of , an effort he&s undertaking with fellow photographer
to visit remote locations and document the skies there. Their goal is to underscore the issue of light pollution and the damage it causes. I support this effort.
Watching this video and reading about the park, I have to add this place to my ever-growing list of spots on Earth I wish to see. It&s no coincidence that many of these are remote, difficult to access, and not well known. All of these are ingredients that add up to a dark sky and spectacular viewing at night. I sometimes wonder if there are enough nights to visit them all.
I&ve written about some of Mehmedinovic& check these out:
On Sept. 30 at approximately 10:30 UTC (06:30 EDT), the Rosetta mission will come to an end.
After many days of slowly approaching the comet 67P/Churyumov-Gerasimenko&sending images and data back to Earth the whole way&it will settle down onto the surface of the bizarre little worldlet, what the European Space Agency is calling a &controlled impact.& And at that moment, the spacecraft is expected to stop transmitting.
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It&ll have done what it came to do: , , and
for the first time in human history.
That&s quite a docket. And it performed these tasks amazingly.
Sure, the situation with the Philae lander could&ve gone a lot better. , and even in failure it succeeded in teaching us more about the surface of a comet.
: Ma&at, an area that has some &active regions& sending out plumes of gas. It&s located on the smaller of the comet&s two lobes (, about halfway from the neck up to the top). It& if active regions are still doing their thing, we&ll get some truly amazing close-ups of cometary outgassing, the phenomenon that creates the fuzzy head and long, long tail of a comet.
The ESA hasn&t released too many details just yet, but they expect to have more soon. I&ll let you know when I hear.
for current info, too.}