An Irregular Mystery
Irregulars are pretty much like the name says: They tend not to have an overall structured shape, but are, well, irregular. Still, despite that, some do have a semblance of shape, and it’s not always clear why.
Take IC 3583, for example. That’s the galaxy above, in a gorgeous Hubble Space Telescope image. It’s definitely irregular, but not quite. It appears to have a bar running across it, a thick rectangular structure. Many galaxies have bars (the Milky Way does across its core), even some irregulars. Usually they form from the weird way gravity works in galaxies; instead a single massive object in the center like the Sun anchoring the solar system, the mass of the galaxy is spread out, and that can cause odd structures to form like spiral arms and bars.
It’s possible a bar like that could get its start if the galaxy interacted with another one; the gravity from a bigger galaxy can pull on the smaller one and distort it, causing matter to move around and form bars like that.
As it happens, IC 3583 sits very near a much larger galaxy, the spiral M 90—which itself looks weird; it has long streamers coming out of it as if it recently encountered another galaxy.
Aha! So is that it? These two had a cosmic tryst, both leaving the encounter a little shaken?
Not so fast. They appear to be close in the sky, but are they close together in space? Two objects can appear to be next to each other but at vastly different distances—like looking out your window past a tree in your yard to the mountains kilometers away. So it’s a legitimate question to ask if IC 3583 and M 90 are actually physically close to each other.
And the answer is … we don’t know. One way to get the distance to a nearby galaxy is to look at some of its brightest stars. We know how much light those stars give off, so by measuring their apparent brightness, we can get a distance to the galaxy.
And that’s where this gets weirder. M 90 is a member of the Virgo Cluster, a nearby and decently large group of galaxies. We’re pretty sure M 90 is a member, and that puts it about 60 million light-years away.
But looking at the stars in IC 3583 indicates it’s only a little more than 30 million light-years away, well in the foreground of Virgo. If that’s the case, the two galaxies are unrelated, despite appearances.
But wait! I said M 90 looks weird too; how can that be then? It turns out that galaxies like M 90 can be moving through the cluster rapidly, and the gas that exists between the galaxies can strip off the gas inside of rapidly moving galaxies. It’s like being in a car when your dog decides to, um, make a foul odor, so you open the windows, letting the air blow through the car, stripping away the mixture of methane, hydrogen sulfide, and mercaptans.
So M 90 may be odd looking because it’s ramming through the cluster, and IC 3583 may look odd because sometimes irregulars are just odd looking. Coincidence.
I know that’s not an entirely satisfactory answer, but here we are. Galaxies, even nearby ones, are still quintillions of kilometers away, and that’s a long haul. It can be difficult to know everything about them … but then, that’s why we study them! We know way more about them than we did a century ago, but that doesn’t mean our knowledge is complete.
Science is a journey. There may not be a single, vivid end to that journey, though it tends to steer toward the path of reality. The fun part is the learning, of solving mysteries along the way. We may never finish—I certainly hope not!—but there’s a lot to see and do along the way.
Follow-Up: Why the House Science Committee’s Climate Change Denial Is So Wrong
Last week, I wrote about an appalling tweet by the U.S. House of Representatives Committee on Science, Space, and Technology. The committee—currently run by a GOP majority—has a history of outrageous climate change denial, and also has a history of tweeting about it.
But even for them, the tweet from Thursday was outrageous: It linked to a ridiculously bad article by climate change denier James Delingpole, who is known for ramping up the hyperbole to 11 when he writes on global warming. He in turn got his bad data from another noted denier, David Rose, writing for the Daily Mail, the Mos Eisley tavern of anti-reality aficionados.
The claim made by Rose is simple: Temperatures since February 2016 have plummeted by a full degree Celsius in more recent months, casting doubt on the reality of global warming.
As I pointed out in my own article (and with far greater detail given by Tamino at the blog Open Mind), Rose’s claim is completely wrong. He cherry-picked data so severely that they’re essentially meaningless; the equivalent of flipping a coin once, having it come up heads, and then declaring it always comes up heads.
He looked at patchy data with high uncertainty from a very short time period and tries to make conclusions about it. What he (and in turn Delingpole and then the House Committee on Science) ignored was the trend. These shenanigans have been graphically debunked by climatologist Gavin Schmidt, who is the director of the NASA Goddard Institute for Space Studies, and is a noted expert in climate change.
To create this animation, Schmidt used land surface temperatures from GISTEMP, which is measured using a variety of methods including meteorological stations. He shows that yes, there is a large drop from earlier this year to October, due in part to El Niño subsiding. If all you see is the first frame of this animation, you might suppose something really is weird!
But there’s more. The second frame shows the same measurements going back much further in time, to 1970. The y-axis is what’s called the “temperature anomaly,” the deviation from some average (in this case, the temperatures from 1951 to 1980; if the anomaly is 0, then you’re right on average, if it’s a degree above average it’s shown as +1, and so on). As you can see, once you look back more than a few months or even years, there is a clear upward trend to the temperatures.
The third frame overplots the average temperature for each year in red, making the trend more clear (the dashed line is an estimate for the rest of 2016 using previous years as a guide). The fourth frame corrects those averages for El Niño (the technical name is El Niño-Southern Oscillation, or ENSO); it’s actually not a huge correction, and again the trend is clear.
The fifth frame shows a mathematical fit to the data to just show the trend, and as you can see it’s heading up.
The other thing to notice here is that we see lots of very short-term fluctuations, some swinging more than a degree over small periods. But that’s not surprising! The shorter the time, the more you expect the temperature to move; the average daily temperatures over a week can be all over the place, but the annual average temperatures should be relatively stable from year to year.
Yet, despite that, the trend is obvious: The world is heating up.
This is precisely why we say Rose was cherry-picking. Whatever his motivations, he only showed a very limited slice of what’s really going on, and in that way hid reality from everyone who didn’t know to look deeper.
Or who didn’t want to look deeper. As I’ve written before, the science is the science, but the inconvenient truth about global warming is that it goes against a lot of political ideology, especially when that ideology is fueled by money from the oil industry.
And without a doubt that’s why the House Science Committee took to Twitter; it wanted to advance its dogma, truth be damned. It is not interested in actual science, or in reality. It is only interested in its agenda, and that agenda is to further the cause of fossil fuel, even if it means setting the world on fire.
The House (Anti-)Science Committee Strikes Again
The House Committee on Science, Space, and Technology is, ironically but shocking to no one who understands the majority party, quite anti-science. For years now, the committee and its chairman, Lamar Smith, R-Texas, have been merciless in their attacks on both climate scientists and the National Oceanic and Atmospheric Administration. Smith—who receives a large amount of funding from fossil fuel interests—has been subpoenaing NOAA staff and data repeatedly in what is a transparent attempt both to create a chilling effect and to directly prevent them from doing their very important research into human-generated global warming.
The committee's Twitter account often reflects this ideology. And Thursday afternoon, to the dismay of many, they tweeted a climate-denying “news” story from Breitbart.
Yes, that Breitbart, the racist, misogynistic über-right-wing site that calls itself a voice for the “alt-right” movement, which is—as my Slate colleague Jeremy Stahl says—composed of “neo-Nazis in suits and ties.”
The content of this tweet is the same sort of thing you’d get if you fed a bull 20 kilos of Ex-Lax and stood behind it for a while. Global warming, of course, is real. The Breitbart article in question is written by James Delingpole, a flat-out climate change denier who has a history of writing grossly misleading articles about global warming. He gets this information from yet another climate change denier, David Rose, who wrote an article for the execrable Daily Mail claiming that global temperatures have dropped by an entire degree Celsius since this summer. Contrary to what the Daily Mail might have to say, global temperature is indeed increasing.
In a nutshell, Rose is guilty of extreme cherry-picking. He looked at a single temperature data set from a specific layer of the Earth’s atmosphere and only used measurements over land. And to make matters worse, he only used data going back to 1998, a big no-no: That year was unusually warm, so starting there falsely makes it look like temperatures haven’t risen much.
He also is chasing local fluctuations and ignoring the decadeslong trend. And that trend is up. The Earth is heating up. If you want more details, Tamino at Open Mind debunks Rose’s claims quite thoroughly.
As wrongheaded as it is, this kind of climate denialism is de rigeur for people whose stance is so anti-science. I’m used to it, awful as it is. But it’s the fact that the house committee linked to Breitbart that’s so disturbing.
And this isn’t even the first time this Twitter account has linked to a Breitbart article. It did so on Sept. 8:
And then, after finding all this out, I found (via Karen James) that Committee Chairman Smith actually has written for Breitbart! As physicist Robert McNees points out, this has been going on for some time now.
And mind you, all this was before Trump was voted into office. These tweets, and the information they cite, are a scary reminder that climate deniers will feel emboldened by Trump’s election. Trump’s team is already planning to cut global warming research at NASA. As winter approaches, we’ll likely see more reality-challenged senators bring in snowballs to the floors of Congress and say, “What global warming?” every time a cold snap arrives, even though a lot of the brutal “polar vortex” conditions are actually tied to the effects global warming.
The good news is some in Congress do recognize the reality and the importance of climate change. Rep. Don Beyer, D-Va.*, for example, who tweeted:
This isn't factual, it's embarrassing, and Breitbart is not a credible news source. We need to bring *science* back to the Science Committee https://t.co/oZ6GfFAlUI— Rep. Don Beyer (@RepDonBeyer) December 1, 2016
Good on him! We need more people like him in Congress willing to speak up against this sort of denialism.
The stakes here are as high as they can get. Climate denialism by Breitbart now gets the imprimatur of the federal government. This cannot stand. Act accordingly.
P.S. If you want to contact the committee directly about this, its phone number is 202-225-6371. If you do, be brief, and be polite! If you have a representative on the committee, mention that as well.
Correction, Dec. 2, 2016: I originally wrote that Don Beyer was a representative for Maryland. He's from Virginia.
Russian Resupply Rocket Lost During Launch
News is still coming in right now, but it looks like a Progress capsule loaded with supplies for the astronauts on the International Space Station was lost as it was heading up into space this morning. It was uncrewed, so there was no loss of human life.
Jason Davis at The Planetary Society has details, and you can also get more at SpaceFlightNow. The launch started off well, but the third stage cut off prematurely. Contact was lost a little over six minutes after liftoff, and Roscosmos, the Russian space agency, has confirmed the loss of the vehicle 190 kilometers over the Tuva mountains in south central Russia; the Progress capsule lost altitude and burned up in the atmosphere. There are unconfirmed reports of debris in the remote area as well though no injuries reported.
The good news is that the ISS is well stocked, and a Japanese supply ship is due to launch in a week or so, so the astronauts are in no danger.
I’m keeping my ears open for more news; it’s unclear how this will affect future Russian launches, including astronauts to ISS. I’ll note SpaceX just announced their return to flight mission for a Falcon 9 on Dec. 16; this will be their first launch since the pre-launch explosion of a Falcon 9 during fueling on Sep. 1, 2016. That’s good news, as they have several resupply missions planned to ISS as well.
More info will be added here as I hear and confirm it.
How the Moon Got Its Weird
Our Moon is really weird.
I mean that literally. It has a lot of physical qualities that are pretty hard to explain. For example: It’s big, fully a quarter the diameter of the Earth. Excluding Pluto and Charon, it’s the highest known ratio of moon to parent body size for any large object in the solar system.
There’s more. All other moons in the solar system orbit over their parent planet’s equator. Our Moon’s orbit is tipped by much more; it actually is tipped 5° to the Earth's orbital plane around the Sun; the Earth itself is tipped by 23° to that.* Also weirdly, while there are some differences, overall its composition is similar to Earth’s. That’s unusual too; most moons are way different than their planets.
A lot of these problems with our Moon were solved when the Giant Impact hypothesis was proposed. Early on in the solar system, a disk of material orbited the Sun, and it was from this disk the planets formed. Small bodies condensed out of it, collided, and grew to become the planets. At some point, tens of millions of years after it initially formed, the Earth was whacked by a Mars-size object at a glancing angle. This flung a huge amount of material into space, which formed a disk over Earth’s equator. The Moon coalesced from this ejecta, and the Earth was left spinning rapidly, with a day just five hours long. Over time, interactions between the Earth and Moon slowed our spin and moved the Moon out, away from the Earth to where we see it now.
That explains a lot of the weirdness we see from the Moon; its unusual size is due to the large amount of material blasted into space, for example. But there are problems. If the Moon formed over the equator, why is its orbit tipped by so much now? Also, in the impact models, the Moon should have a lot of material from the impactor, but instead is closer to an Earth-like composition. Why?
A group of scientists think they may have found the answer. And as a bonus, it explains yet another odd thing: Why the Earth is tilted by 23° to its orbit.
What they propose is a modification to the giant impact idea. In their model, they have a much more energetic impact. The tremendous power of the collision set the Earth spinning with a two-hour day, faster than in the classic impact hypothesis. The higher energy also meant the material ejected mixed a lot more, so that both the Earth and Moon wound up with similar compositions.
Then comes the really strange part. You know how a kid on a swing can make their arc go higher by pumping their legs? By doing that they transfer the energy of their legs’ motion into the swing. But they have to time it right to make it work, doing it at just the right time in the arc. When two cycles line up like this it’s a called a resonance, and it’s a huge influence on the motions of moons and other bodies.
After the Moon formed, it started moving away from the Earth due to the complicated dance of gravity and tides. I explain how this works in Crash Course Astronomy: Tides, if you want the details. The outcome of this is that the Moon’s orbit slowly expanded and the Earth’s spin slowed.
In the new model though, there’s a twist: The giant impact torqued the Earth hard, so much so that our planet’s pole was aimed more toward the Sun than it is now. This changes that tidal evolution of the Moon. As it moved away it went through a series of resonances, some connecting the way it moved away from Earth with the Earth’s motion around the Sun (like the way a kid’s legs connect with the swing’s motion).
What the scientists found in their models is that this affected both the tilt of the Moon’s orbit as well as the tilt of the Earth itself. As the Moon’s orbit expanded, it also moved around, changing its orientation. The Moon’s tides tugged on the Earth all that time, eventually yanking the Earth closer to being upright (the Earth’s orbit was unaffected, though).
In the end, the Moon settled into its current orbit, tipped 5° to the Earth's orbital plane, and the planet stayed at its 23° tilt to its orbit around the Sun. This video shows the effects graphically:
The Sun is off to the left, and the Earth’s axis points near it. As time goes on (starting less than a million years after the impact) the Moon’s orbit changes in orientation, tilt, and shape, and the Earth’s axis changes, too.
I’ve left out a lot of details because they’re complicated and would take a lot to explain (feel free to read the paper, but there’s a lot to it). Still, this is the meat of it. The big question is: Is this what actually happened 4.5 billion years or so ago?
That’s a different question. Just because this new idea explains more stuff we see now doesn’t make it right. Lots of other ideas have come along, and no doubt more will. Perhaps this idea is correct, and still needs modification (for example, we know a lot of things happened after the Moon formed; its far side and near side are really different, and more hypotheses have been proposed to explain that). Maybe something better will come along that explains even more.
But that’s science! For a long time—centuries, millennia—we had no more than guesses on how the Moon formed. As we studied it more we learned more about it, and were able to cull a few hypotheses. Then we went there and got samples, pieces of the Moon we could study in the lab. More mysteries surfaced, and the giant impact idea explained a lot of them. But it’s been modified, over and again, tweaked here and there, and now we may very well be closing in on the complete history of how our gigantic satellite came to be.
There are a lot of reasons I love science, but one of them is that it doesn’t flinch from telling the big stories, and welcomes changes to make the story better.
*Correction, Dec. 1, 2016: I originally wrote that the Moon is tipped 5° to the Earth's equator, not the Earth's orbital plane.
Another Jumping Sun Dog
Just recently I wrote about one of the coolest and weirdest weather/optical phenomena I’ve ever seen: crown flashes, also called jumping sun dogs. They’re streamers of light above storm clouds that appear to dance and flash, sometimes quite rapidly, looking like search lights or huge light sabers.
They’re almost certainly caused by long ice crystals above the cloud that align themselves with the cloud’s electric field. If you see them from the right angle, they bend (or refract) the sunlight toward you, causing the glow. When lightning erupts from the cloud to the ground (or inside the cloud) the electric field changes radically, realigning the ice crystals. When this happens they suddenly bend sunlight in a different direction, causing the glow to shift.
By coincidence, a BA reader named Mikhail Chubarets sent me an email a few months back (before I wrote the article linked above), letting me know about an amazing video of a crown flash, but I missed his email! I was going through some old ones and spotted it, so now I get to share this short but way cool video with you:
The video was taken in Zvenigorod, a city in Moscow Oblast in Russia, on July 3, 2016. It really shows a lot of detail, and I gasped out loud at the 1:25 mark when it shows the glow sweeping rapidly like the blade of a sword into a new position.
I have some mixed feelings about this, to be honest: While this is one of the most astonishing optical phenomena I’ve ever seen, the things is, I’ve never seen one for myself. I recently was able to scratch Kelvin-Helmholtz clouds off my “to see” list, as well as (yikes) a tornado. But this? Crown flashes are pretty rare; besides having the ice crystals aligning correctly you also have to be in the right spot for the geometry to line up, otherwise the sunlight isn’t bent your way. They’re rare enough that I hadn’t even heard of them until a couple of years ago.
It seems unlikely I’ll ever witness one. Ah well. I can add that to a long list of things still to witness (like a total solar eclipse, a full-blown aurora, a display of undulatus asperatus, and more). I do get around, and I do tend to look up, so I can still hope. There are a lot of truly wonderful things to experience on this planet of ours.
A (Frozen) Great Lake of Water Is Found Beneath the Surface of Mars
Mars has long been a target of human curiosity. A blood-red eye in the sky, hanging, baleful. Our understanding of it has changed over time; it was thought to be somewhat Earth-like for a while, but then we sent space probes there and found it to be a desiccated, dead world.
Well, at least for now. We have pretty conclusive evidence it once had plentiful liquid water on the surface, including lakes, rivers, and even oceans. That was eons ago; the solar wind stripped away the atmosphere from Mars, and the water mostly boiled away with the air.
Mostly. We’ve known for a long time there’s lots of water ice on the planet; both poles have water ice caps on them several kilometers thick (in turn capped by seasonal layers of frozen carbon dioxide —dry ice— a few meters thick). You kinda expect that at the poles. But there’s also evidence for water just under the surface at mid-latitudes: Small impacts from asteroids have excavated ice that can be directly seen. These are wee craters, so it’s not clear just how much ice there is down there.
But now scientists using a radar mapper on board the Mars Reconnaissance Orbiter (or MRO) have found more water ice at these lower latitudes, and a lot of it: The volume is enough to fill Lake Superior, the largest of the Great Lakes in North America.
Yeah, that’s a lot of ice.
It’s located in a region called Utopia Planitia (Trek fans will recognize this as the location of the Starfleet Yards where the Enterprise-D was built), at a latitude of 45° north, so quite literally at mid-latitudes. While it’s only a tiny fraction of the total water ice known to exist on (or under) Mars, it doubles the amount known at these latitudes.
It was found using a radar mapper on MRO. Called SHARAD, it sends pings of radar down to the surface, which are reflected back up to the satellite and recorded. Different substances reflect radar differently; the rocks on the surface aren’t particularly good at it, which is why the radar can penetrate the ground. Water, on the other hand, reflects radar quite well, so SHARAD can detect water ice down to a depth of a kilometer below the Martian surface.
Scientists focused their attention on a region in Utopia Planitia that features lots of odd, scalloped terrain (aresain?), which is similar to places on Earth in the Arctic that have underground ice. Combining the data from over 600 MRO passes indicates how much ice there is. The area of the ice deposit is over 300,000 square kilometers and the thickness ranges from 80 to 170 meters. So yeah, that’s a goodly supply of ice.
This is pretty good news for future exploration and colonization plans. Ice is critical for Martian living; it can be melted to drink, broken into oxygen and hydrogen for air and rocket fuel, and can protect inhabitants from solar storms (on Earth our air does this, but Martian air is less than one percent as thick as ours; ice does an excellent job of absorbing radiation).
One last thing: How did the ice get there? One idea is that Mars’ axial tilt varies wildly over time. When it flips, the poles become much closer to the previous equator. The ice sublimates, turning into a gas, which then recondenses in other locations. It can mix with dust and snow out in the mid-latitudes, eventually getting buried.
That’s amazing. An entire planet flipping over like that! It’s hard to imagine what chaos that would wreak on the climate, even for a planet with so little air. Happily, our Moon provides stabilization against this kind of event; it torques the Earth’s axis and prevents it from making big excursions.
Mars is weird. But that’s good! Studying it helps us put the Earth in context with the other planets, and in turn helps us understand our own planet. And that’s good, because we live here.
Follow-Up: More on Trump’s Catastrophic Plan to Gut NASA’s Earth Science
As expected, the days leading up to Donald Trump’s inauguration are like the timer on an atomic bomb ticking down to Armageddon. Every day there’s some new horrific thing he and his cronies do, and the only predictable thing they do is find the worst possible choice to make in any given circumstance.
This was brought home, hard, when Bob Walker, a top Trump adviser, recently said that the new administration will gut NASA’s Earth science program. The reason: Trump’s long-standing and implacable climate science denial. And this, of course, is the inevitable outcome of decades of Republican attacks on science.
When I wrote about this the other day, I went into some detail, outlining the blatant hypocrisy of Walker’s statements; essentially everything he said about climate change was provably false, and the charges he aims at climate scientists can actually be lain at the feet of the GOP.
Not long after I posted my own piece, the CBC radio show As It Happens posted an interview with Walker where he reiterates his erroneous claims. They then contacted me and asked me what I thought of Walker’s statements.
Yeah, you can just guess how I feel about them. I talked with As It Happens host Carol Off about it, and the interview is online. They have a transcript as well, but it doesn’t include everything I said; I recommend listening to the whole interview (which is roughly nine minutes) so that you get all the info. As a bonus, you’ll also hear just how angry and frustrated I am by this utter disaster.
In the interview I mention a few things I want to make sure everyone sees. One is that Walker tries to downplay the “climate consensus,” the fact that there is overwhelming agreement among climate scientists that global warming is real and caused by humans. The best overview of this is at Skeptical Science. John Cook—who writes for that site and is also the lead author on one of the many studies about the consensus—also wrote a great article about it for the Conversation.
Ninety-seven percent of climatologists agree on this. 97 percent. Don’t buy into Walker’s nonsensical claims about this; he’s using thin rhetoric to sow doubt where it doesn’t exist.
I said that Exxon knew about fossil fuel–induced global warming for 40 years; DeSmogBlog has more on that. It’s pretty damning.
Also in the interview I mentioned Marshall Shepherd, who was president of the American Meteorological Society. He coined the wonderful term “zombies of denial,” so please read more about that.
We need to arm ourselves against the barrage of weaponized denial we’ll be facing for the next four years. Trump himself, and his proxies as well, have no trouble at all just bare-faced lying to the American public. We must stand ready to fight against this. Whether it’s the racism, the xenophobia, the misogyny, or the attacks on science, it is no exaggeration to say that our culture, our country, and even our very existence depend on us.
Climate change is already one of if not the biggest threat our species has faced. I still have hope: When challenged, Americans have a history of meeting adversity head on. As I’ve written before:
When Americans are challenged, we rise up and do our best. I honestly and truly think that we can, that this is an opportunity to show the world that we won’t stick out heads in the sand. We’ll face this issue, and we’ll figure out how to minimize it, how to circumvent it, how to manage it. I don’t believe in phony platitudes, or empty motivational slogans, so my words here don’t ring hollow to me. They’re simply the truth. We went to the Moon, we put rovers on Mars, we look outward to the Universe and forward into the future. That’s America.
Climate change is one of the largest existential threats we face today. It’s time to face it down.
I wrote that before the election, but it’s still true. It’ll just be a lot harder with Trump and the GOP in charge. That means we have to dig in and deal with them, too. We can do this. We have to.
Starry Starry Swing
Longtime BABlogee and music composer Greg La Traille sent me a note letting me know about an amazing art exhibit in Zürich, Switzerland, called “Starfield,” but really it should be called “Star Swing.”
Why? Well, for one thing, it’s a swing. But not just an ordinary piece of playground equipment: It’s connected to a Microsoft Kinect that uses the height of the user’s eyes, measures the angle of the ropes holding the swing, then calculates the trigonometry necessary to make it look like you’re swinging over the galaxy itself!
I love this. What fun! And because the projection is digital, it can be swapped out with any data where 3-D info is available (or can be simulated). You could swing over the Moon, or a black hole, or Saturn’s rings … or scenes on Earth like, say, Angel Falls or the top of K2. Starfield uses data from the WorldWide Telescope, too.
The idea comes from a French art collective called Lab212 (they have a lot of other cool experimental art installations worth checking out, too), and was originally created by Cyril Diagne and Tobias Muthesius. It’s at the Museum of Digital Art in Zürich.
I make no bones about having a weak stomach; reading in a car makes me ill, and playing on a kid’s swing can be somewhat touch-and-go for me. So I wonder if riding on Starfield would be a good idea for me.
Still, I’d love to find out. What a wonderful and lovely idea. Math! Science! Art! They’re all related; a combination of how the Universe is and how we experience it. When they are intertwined, it enriches them all.
On March 8, Earth lapped Jupiter in their race around the Sun. Earth orbits closer to the Sun than Jupiter, and so moves much more rapidly. Like a car on the inside track passing one on the outside, this meant that Earth was as close to Jupiter as it would be all year.
Astronomers call this event opposition, because it means the outside planet is opposite the Sun in the sky as seen from the inside planet. So, to us on Earth, Jupiter rose when the Sun set, was up all night, and appeared as big through a telescope as it would until the next opposition (which will be on April 1, 2017).
During the March opposition, planetary photographer extraordinaire Damian Peach aimed his 35 cm telescope skyward and shot video of the huge planet. Using software to pick and choose which frames minimized the blur of the atmosphere, he assembled the amazing image of Jupiter shown above. It “unwraps” Jupiter, mapping the spherical surface onto a rectangle. This distorts some of the features near the poles (like when a similar map of Earth makes Antarctica stretch all the way across the bottom, or magnifies how big Greenland is) but still gives a great overview of what’s what.
The most obvious feature is, of course, the Great Red Spot, a persistent storm that is at least four centuries old, and possibly far older. For reasons unknown, the Spot has been shrinking of late, but it’s still big enough to swallow the entire Earth without our planet touching the sides.
My favorite part of this image is the turbulence downstream of the Spot, as the circulating atmosphere flows around it. It’s much more apparent in the big version of this image, and I encourage you to take a look.
You can also see the banding of Jupiter, circulating weather systems that stretch all the way around the planet (you can find out all about this and more in my Crash Course Astronomy episode about Jupiter). Smaller pale circular storms dot the midlatitude southern hemisphere, and it’s easy to spot similar features all over the planet.
Using all the best frames from the observations over March 18 through 22, Peach created this stunning video of the monster planet rotating.
Jupiter spins once every 10 hours, so Peach had to match each image taken over five days carefully to get them to fit into the animation. It really gives an impression of the immensity of the planet; remember, 11 Earths would fit across Jupiter’s face!
Jupiter is always one of my favorite targets when I take my own telescope out. It’s big, easy to see (it’s the fourth brightest natural object in the sky, after the Sun, the Moon, and Venus), and the motions of its four biggest moons are easy to spot night after night, and sometimes in just a few hours.
Unfortunately it’s not well situated to observe now; it rises around 3:30 in the morning and sets in the afternoon. But starting in 2017 it’ll be gracing our early evening skies again, and I hope for a chance to take some time getting reacquainted with it. If you have an opportunity to see it—and many astronomy clubs have public star parties—I urge you to take it. Your view may not be as a good as Peach’s, but it hardly matters. Seeing a planet like Jupiter with your own eyes is an experience you won’t soon forget.