Spiral galaxies are just so danged pretty.

Seriously, look at that! It’s an image of the nearby galaxy M63, aka the Sunflower Galaxy, taken using the Hubble Space Telescope. M63 is relatively close to us, a mere 37 million light-years, easily visible in small telescopes. I’ve seen it a few times myself through my own ’scope—I vaguely remember finding it by accident when I was in high school, looking for the more famous M51 Whirlpool Galaxy. They’re not far from each other in the sky, and in fact they aren’t far from each other in space; both are part of a small group of galaxies.

M63 is what we call a flocculent galaxy—the arms are patchy, like tufts of cotton. Roughly a third of all spirals are flocculent, and apparently it’s still not well understood what causes it. One idea is that local gas clouds get stretched and sheared by the galaxy’s differential rotation (that is, stuff closer to the center makes an orbit around the galactic center in less time than stuff farther out).

Another is that star formation is localized, starting randomly in spots in the disk of the galaxy, triggering more star formation around it, creating that patchwork. In galaxies like the Milky Way, the spiral arms themselves trigger star formation, so you get more of a sweeping, grand design to the spiral arms.

Because why not, here’s a (much wider field of view) shot of M63 taken by the Spitzer Space Telescope:

Spitzer detects infrared light emitted by warm objects, so what you’re seeing here is mostly dust gently heated by nearby stars. The arms look a little more organized here, but you can still see they’re patchy. 

I love big, sweeping spiral galaxies, but there’s something to be said for flocculent ones as well (like NGC 2841, NGC 3521, and NGC 1398). And besides being just pretty, they also show us that there’s more than one way to make a spiral arm, or to spawn millions of stars.

Nature’s fairly creative. And it has a broad canvas upon which to work.

One of the best innovative uses of remote cameras is when space agencies strap them onto the sides of rockets. It’s probably the closest most of us will ever get to seeing what it’s like to hitch a ride into space.

On April 3, 2014, a Soyuz rocket lifted off from French Guiana carrying Sentinel-1A, an Earth-observing satellite (the first in the ambitious Copernicus program, meant to observe our planet’s environment). Two rocket cams were mounted on the side of the upper (Fregat) stage, looking down, and the view they provided was amazing.

There are a few key moments to keep your eyes on:

• 00:58 Main engines start.
• 1:10 Liftoff and rotation to correct attitude.
• 2:09–2:21 Time lapse speeds up (to save time), and you can see the exhaust flame expand as the rocket gains altitude and air pressure drops.
• 2:27: The four external boosters are jettisoned. According to Anatoly Zak of Russian Space Web, this is the first time a Soyuz rocket staging was ever seen in flight. Impressive! I love how their tumbling is synchronized for the first couple of flips.
• 2:47 The fairing protecting the satellite is ejected, and you can see it fall past the rocket.
• 3:17: The second stage separates and the third stage ignites.
• 4:20 Sentinel-1A is ejected into orbit.

We (and by “we” I mean humans) have had some setbacks in the past year with getting rockets launched into space, especially those supporting human exploration. Still, three more people were successfully sent to the space station recently on a Soyuz, which performed well after some recent, ah, issues. SpaceX is planning a return to flight in November after a catastrophic failure in June led to the loss of a Falcon 9 rocket and Dragon capsule with supplies for ISS. Blue Origins is looking toward the future of launches. Boeing is moving along with its manufacturing of the CST-100 capsule, now named Starliner.

If voters can convince Congress to actually fund the Commercial Crew program to its needed level, then in a couple of years we’ll be launching Americans in American rockets from American soil once again, too.

The future of spaceflight can be ours, if we want it. All we really need is to the will to make it so.

Just when I think I’ve seen every variation of time-lapse animation of the night sky, along comes Joaquín Baldwin with his very clever and captivating short animation “Scintillaris”:

Ha! I love how the music punctuates his plucking the stars from the sky. Very nice.

It took three hours to record this video in the Mojave desert. It’s made up of individual and continuous 15-second exposures, long enough to capture the faint Milky Way in the background and still show nice, smooth motion of the stars and clouds. Baldwin had to follow a careful script to get it right, and hold each pose for the duration of each frame (except for the end, where he moved around to create the creepy-cool blurred effect).

My thanks to Joaquín Baldwin for letting me know about his work!

High mass stars are a bit scary.

These are beasts more than roughly eight times the mass of the Sun. The rate at which they generate energy goes up hugely with mass, so a star with eight times the Sun’s mass shines thousands of times more brightly. A 20 solar mass star can be 100,000 times as bright as the Sun! The highest mass stars, about 100 times beefier than the Sun, are millions of times brighter.

And if that’s not enough, they can also explode. As in, kaboom, no more star. Supernova.

How can an entire star explode? It turns out that there’s a lot going on deep in the hearts of these monsters, and it all leads to a violent, nasty death. I explain how in this week’s episode of Crash Course Astronomy.

Two quick misconceptions debunked: First, the Sun cannot explode. It doesn’t have what it takes; there’s not enough mass to create iron in its core. Our Sun will go the way of other low mass stars: blowing off its outer layers, (maybe) becoming a planetary nebula, and then finally a white dwarf.

Second, there are no supernova progenitor stars close enough to us to hurt us. A supernova has to be pretty close to Earth to do us any substantial physical damage, and there just aren’t any stars that can explode that nearby (not even Betelgeuse). Well, more or less.

Gamma-ray bursts are a different matter … but even then any candidates for those are probably too far to hurt us. If you want details, great! You’ll get ‘em … in a future episode. Stay tuned.

As a reminder, we have a playlist for the entire Crash Course Astronomy series that’s aired so far. One-stop shopping!

Y’know, I can rail about trillions of tons of ice melting from the poles, and how we’re dumping billions of tons of CO₂ in to the air every year, and how our sea levels are rising, and how 97 percent or more of climate scientists agree we’re heating up … but in the end, I suspect I won’t have nearly as big an impact on the public as simple, funny videos like this one (maybe kinda sorta NSFW):

Ha! Exactly right. Funny how a simple shift of venue makes it obvious that climate change deniers really don’t make any sense at all.

And if you’re dealing with someone who, despite the tsunami of evidence that all of this is real and our fault, then let me make one more point.

A lot of deniers say “The climate’s always changing; sometimes it’s hot and sometimes it’s cold.” If that were true, then you’d expect that if you looked at temperature records in some region over the past century or so, you’d see just as many high temperature records as low, right?

But, if global warming is happening, you’d expect to see more high temperature records than low ones in more recent times.

Guess what?

Two scientists did just this, using records in Australia. Up until 1960 they found just as many high records as low … but from then on highs outnumber lows. And in 2000–2014, record heat outnumbered record cold by 12 to 1.

Now watch the video above again. I try to be polite when I argue a point, try to maintain some civility.

But when you’re ridiculous, what you deserve is ridicule.

Tip o’ the thermometer to Climate Denial Crock of the Week.

The image above is the newest view of the 92-kilometer-wide Occator crater on Ceres—the one with the bright spots in it. This shot, taken when the Dawn spacecraft was only 1,500 kilometers (915 miles) above the surface of Ceres, shows far more detail than we’ve seen before. It’s actually a composite: Two images combined, one that exposes the bright spots well, and another that shows the darker material in the crater around it exposed correctly.

Many of the bright spots are now resolved, and are clearly localized to specific places. The central region of the crater is not just a blob, but has some places where the coverage with the brighter stuff is full, and others where it’s spottier. In the upper right, many spots are obvious, as well as a fainter covering of brighter material on the surface.

There’s more new stuff to see, too: Linear dark markings that look very much like cracks in the surface are now visible. There are a few in that patch of brighter material in the upper right that are hard to resolve, and another series (Ceres?) of them that appear to follow the topography at the bottom of the photo near the crater rim. The ones at the bottom are obviously cracks; perhaps created as material in the crater floor subsided. It almost looks like something flowed there, hardened, and shrank to cause the cracks.

I’m speculating, of course. We still don’t know exactly what these bright spots are, but the cracks may be a clue. We know there’s lots of water ice inside Ceres, and these spots might be ice that has been squeezed out. The water may in fact be salty; if the ice on the surface sublimated (turned into a gas) due to sunlight hitting it, then the salt would be a residue, like getting salt crystals on you when seawater evaporates after you swim in the ocean.

I’ll note the crater rim shows very obvious evidence of collapse; the walls are quite steep, and there’s lots of material piled up inside the crater. If you look carefully you’ll see brighter spots along the rim wall, though those may just be somewhat fresher material (and not necessarily ice or salt).

Images like this are truly wonderful. We’re getting a close-up look at a protoplanet! As I wrote in an earlier post, Ceres is usually thought of as the largest of the asteroids, but a team member on Dawn told me they think of it more as a protoplanet: An object that got large enough that it started taking on the properties of a planet. Asteroids, on the other hand, are essentially leftover rubble, the building blocks of planets that have undergone a lot of impacting and shattering.

I still haven’t heard anything about the mineralogy of the surface; hopefully the detectors on Dawn will be able to distinguish between clean water ice and salt with enough resolution to tell us what these spots are. We’re still awaiting the scientific analysis of all the data. Certainly the spots are eye-catching, but more than that they’re an important clue to the surface, interior, and history of Ceres.

What are they? Maybe we’ll know soon.

Well, this is interesting: Astronomers looking for exoplanets—alien worlds orbiting other stars—have found a binary system (two stars orbiting each other) where both stars have a single planet orbiting them!

Plenty of circumbinary planets have been found, where the exoplanet orbits both stars at some distance (think Tatooine), but it’s rare to find a binary star where both stars have their own planet (called circumprimary planets).

The binary is called WASP 94AB (the 94^th planetary system found by the Wide Angle Search for Planets, where the two individual stars are called A and B). Both stars are classified as F-types, somewhat more massive and hotter than the Sun. They orbit each other at a distance of at least 400 billion kilometers, about 90 times the distance of Neptune from the Sun.

The planets are both “hot Jupiters,” gas giants that orbit their respective host star closely. One of the planets, WASP 94Ab (planets are given lower case letter designations starting at “b”), was discovered because it transits its star, moves directly between us and the star, blocking a wee bit of its light. Knowing how big the star is, we can determine how big the planet is by how much light it blocks. In this case, it’s 1.7 times wider than Jupiter.

We can also get its mass, because as it orbits the star it tugs on it, and we can measure that effect. The planet’s mass, interestingly, is only about 0.45 times Jupiter’s. So it’s less massive, but much larger than Jupiter. Why?

Heat. It orbits the star every four days, which means it’s very close to this inferno. The planet absorbs that heat, and its atmosphere puffs up, making it much larger than you’d expect.

The other planet, WASP 94Bb, was discovered by accident! Although it does not transit the star, it still tugs on it, and this effect was discovered when the astronomers serendipitously observed WASP 94B at the same time as WASP 94A. They found the planet’s mass to be about 0.6 times Jupiter’s (the size can’t be found because there’s no transit). It takes only two days to orbit the star.

What’s very interesting, though, is that these planets exist at all! We know planets this massive can’t form this close in to stars; it’s too hot for planets to be able to gather enough material to grow that big. The current thinking is that they form much farther out and migrate inward toward the star. When they form, there’s a disk of material around the star called the protoplanetary disk, and plowing through this material drops the big planet down toward the star, eventually stopping when the disk peters out close to the star.

However, there’s more going on with the WASP 94 planets. For one, careful measurements of the first planet show it orbits the star in the wrong direction, opposite to the star’s spin! This retrograde motion, as it’s called, can’t be due to simple migration inward; something else must have kicked the planet in some way to get it moving the opposite direction.

For another, the other planet doesn’t transit, meaning its orbital plane is tilted quite a bit from the first planet. The two stars almost certainly formed together, and have very similar properties, so the disks that formed the planets should be similar. You’d expect both disks would have aligned with the orbital plane of the two stars themselves. But at least one of the planets is out of whack.

It’s possible these anomalies are due to the mutual gravitational influences of the stars, one tugging on the disk of the other. But they’re very widely separated, so this is unlikely (though not impossible). Perhaps WASP 94A has or had other planets that interacted with the planet 94Ab, sending it into a weird orbit.

Whatever happened here, this is an odd system. Hot Jupiters aren’t very common in stars this massive, and so each one having such a planet is a bit weird in and of itself. Only three other binary systems with circumprimary planets like this are known so far.

I love exoplanets! They show such a rich and diverse range of properties, and not all of them are easily explainable. We’re still arguing over the details of how our own solar system formed, honestly, so studying these other systems gives us insight into our own origin story.

Space debris is a growing problem. These little bits of orbiting junk—tools dropped by astronauts during EVAs, nuts and bolts from the deployment of satellites, and so on—are moving a dozen times faster than a rifle bullet, and pose a real threat to the International Space Station and other assets. Even a fleck of paint can be seriously harmful when it’s moving at 25,000 kph relative to you.

To fix this problem, a team of scientists has come up with an idea: Use a telescope planned to go on board ISS anyway to find the junk, then use a bundled fiber laser to zap it.

I have the details in my twice-monthly column for Sen.com. The blogs there are subscription-only for five bucks a month, about the amount you spend on the healthy breakfast cereal you promise yourself you’ll eat when you’re shopping at the grocery store but then throw out when it gets stale a month later. And in this case, you get stuff that’s healthy for your brain and curiosity.

As always, news, pictures, and features there are free.