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We knew that, if the Webb telescope could make it to the L2 Lagrange Point in one piece and deploy properly, this would be an exciting season for astronomers–but, even so, the parade of stunning new images from outer space are marvelous and demand comment. Today’s treasure is a picture of Planet Neptune and its moons as imaged by the near-infrared camera on Webb. The ice giant Neptune is made of strange cold things with a great pall of methane gas over them. Methane gas is very opaque to infrared light (which it absorbs) and so the planet looks like a frosty, haunted bowling ball with glass rings.
Ever since Pluto got demoted to “dwarf planet”, Neptune is the outermost world of our solar system. Yet the great gas giants…or even the trans-Neptunian objects like Eris and Haumea get all of the attention. No space craft has even visited Neptune since Voyage II rolled by in 1989 (the first and last time a probe entered the Neptune system).
Aside from the spectral rings, the image shows some bright sparks in a line along Neptune’s Tropic of Capricorn (which is not called that, but you get the idea). These bright spots are caused by high altitude methane clouds which are made of methane ice (which reflects infrared light better than methane gas does).
The full Webb photo has a striking focal point! Pulling back we see that Neptune’s largest and strangest moon Triton outshines the giant world it orbits. This is because Triton (which is named for the Greco-Roman deity Neptune’s merman super-son) is covered in a sheet of frozen nitrogen which reflects 70% of the sunlight which strikes it–so Triton glows like an aquamarine star in this photo. Ultimately Triton might well turn out to be be more interesting than Neptune: it is the only large moon in the solar system with a retrograde orbit (an orbit opposite of the planet’s rotation). Such an unusual orbit suggests that the moon was a little world captured by the ice giant long ago.
Triton is larger than Pluto and is one of five moons in the solar system known to be geologically active (the others being Io, Europa, Titan, and Enceladus). Voyager II spotted geysers of nitrogen gas venting from the moon. Clearly cryovolcanic activity is taking place below the strange patchwork of old ice (as explained in this confusing yet compelling map/diagram) and lakes of liquid water may exist below the moon’s crust.
I am going to keep staring at images of our strange far-off neighbor world, but I can’t wait to see what Webb photographs next!
Remember back at the height of the pandemic, when the Chinese Yutu-2 rover discovered green blobs on the dark side of the moon? Well, if you somehow don’t remember that, here is my blog post from last year (spoiler, the blobs were lunar rocks). I mention this because the Yutu-2 lunar rover (which I am going to start fully translating as “Jade Rabbit 2” so it sounds less like a ballet dress) is now making international waves with a new discovery–a strange gray cube evocatively designated as 神秘小屋 “magic secret little hut.”
Courtesy of the Chinese space agency, here is a picture of this mysterious lunar object.
Wow! It, um, does look comparatively more like a magic secret little hut (or any sort of outbuilding, really) than the rest of the lunar regolith. As I write this, Jade Rabbit 2 is heading towards the mystery feature, so we should have a better answer about the lunar cube shortly. Based past Jade Rabbit discoveries, I am going to go on record and opine that this is a rock.
However a large square boulder is hardly a disappointment. There are no glaciers (currently) on the surface of the moon eroding erratics and carrying them around, so how did it form and get where it is? If, as seems likely, it was the result of a lunar impact event, then perhaps it can teach us something new about lunar basalt?
Finally, what can the Chinese teach us about drumming up space-exploration support with crazy names and press releases? Their square boulder has made international headlines (in an age of omicron and Olympics controversy!) just because it has a jazzy designation. Maybe we should start giving more space objects Chinese names (a development which is undoubtedly on its way, anyhow). We will keep our eyes on this lunar cube, in the off chance that little gray elves come out and try to sell strange lunar goods to Jade Rabbit. Off-world exploration doesn’t just teach us things: it is fun!
Hi everyone! Sorry that the posts were thin on the ground last week. The head druid told me that I needed to honor the solstice by taking some time to reflect on the meaning of things [citation needed]. Anyway…since I didn’t blog last week, I failed to post these astonishing pictures of Jupiter’s giant moon Ganymede, which were photographed by NASA’s Juno spacecraft as it slaloms though the Jovian system.
Although its lack of atmosphere and pockmarked plains of dust make it superficially resemble Earth’s moon, Gannymede is a very strange and unique heavenly object Of the 200 known moons in the solar system, it is the largest. Indeed it is 26% larger than the planet Mercury by volume (although it is only 45% as massive as the metalliferous first planet). Ganymede has a diameter of 5,268 km (3,273 mi), so each pixel in the full size image of the Jovian moon is equal to a kilometer (although you may want to check out the NASA image to really savor that scale–since WordPress has a noteworthy penchant for scrunching up my images in incomprehensible ways).
Alone among moons in the solar system, Ganymede has a magnetic field, albeit a rather meager one compared to Earth or Jupiter. Scientists surmise that the magnetic field is created by convection within the liquid iron core of the moon–although answers are not forthcoming as to why it has a liquid iron core to begin with (these planetary cores seem to be the real determinant of what planets are like, but I feel like we know precious little about them). Thanks to its size (and maybe thanks also to its magnetosphere), Ganymede has a very thin oxygen atmosphere…but that just creates more question, since elemental Oxygen has a tendency to instantly bond to all sorts of other elements. The 20 percent or so of oxygen in Earth’s atmosphere did not become a mainstay until about 1.5 billion years ago when photosynthesizing bacteria finally became so prevalent that they overcame the constant loss of atmospheric oxygen thanks to oxidation. Hopefully Juno’s survey will help us solve atmospheric mysteries on Ganymede. Ganymede is also believed to have a vast subsurface ocean of icy water tucked away somewehere beneath its surface. Astronomers have reasonably speculated that this Ganymede underworld ocean may contain more water than all of Earth’s oceans combined!
Ganymede is a Galilean moon–which means it was discovered by the great scientist, and is one of the first objects ever discovered to orbiting another planet (I still sometimes imagine the thrill Galileo must have felt when he realized what he was seeing). I wonder what surprises Juno will send back for us!
Here is a beautiful nineteenth century engraving which illustrates how Second Empire French artists imagined the pythia of Apollo. This image is particularly dramatic since the pythia is not only hopped up on divination fumes but is also wrestling with some rather alarming serpents (they don’t quite seem to be pythons, but I suppose when giant hissing snakes are wrapped around you, it is pointless to quibble about herpetology). Although the light falling on the pythia makes her pop out from the rest of the work to such an extent that, at first, she almost seems alone, my favorite part of the print are the interpreters/querents in the shadowy background who are pursing their lips and furrowing their brows as they try to parse out the divine meaning of the oracle’s presentation. This print was created by the master illustrator Émile Bayard who is still famous for his heart-wrenching image of Cosette from “Les Miserables.” Additionally, Bayard was one of the first-ever science fiction artists: he attempted to portray Jules Verne’s space travel novels based on scientific and natural sources (as opposed to basing heavenly imagery on myth and religion–as had been the norm up until the end of the 19th century).
Today is tax day here in America, so perhaps some readers may also feel as though they are wrestling with wrathful serpents of unnatural creation. Alternately some readers may feel that they need to ask a mystical oracle for special clarification (ed’s note: Don’t do any such thing! If you have tax-based questions, please consult a tax professional or contact the IRS). Although it has been a while since I refreshed the answers, you can always head over to The Great Flounder, to ask the piscine sage for secrets of the dark underwater depths! Good luck!
This year Ferrebeekeeper missed the Mid-Autumn Moon Festival…but that doesn’t mean we have forgotten about it. Additionally, in a garden-themed post a few weeks back, we promised a few more late-season pictures from the garden. If only there were some way to combine these two objectives…
Allow me to present the last flower to bloom in 2020…the moonflower (Ipomoea alba). There are still plenty of flowers in the garden and tough blossoms like roses and violas will probably continue blooming until December, but the moonflower bloomed for the first time in October (if that makes sense). There are some reasons this lovely nocturnal vine is only just beginning to bloom now. Not only did I start the seeds late in the year (long after the last spring frost), but it is a tropical flower from equatorial Central and South America and needs a 12 hour day to bloom. The long days of summer get it all confused.
True to its name the moonflower blooms at night (a real plus for Ferrebeekeeper, since I tend to be a night bloomer as well). The gorgeous blossoms form big white perfect circles, like the moon. They wilt away at dawn. Alas, in Puerto Rico or Colombia, the moonflower may be a perennial, but here in Brooklyn, it is definitely an annual. I may only get a handful of flowers, but it was definitely worth the wait! Happy belated Mid-Autumn moon festival! However, this year we get two full moons in October so prepare for further moon-themed posts for the Halloween blue moon!
While we sort things out here on Earth, let’s take a little break and check out how everything is going at a place which is so far away and yet so close–the dark side of the moon. Back at the very end of 2018 the Chinese Space Agency successfully landed a lunar probe on the far side of the moon (the first “soft” landing in that hemisphere ever). China has been diligently working on lunar exploration and, prior to this landing they had already launched a relay satellite named “Queqiao” into operational orbit about 65,000 kilometers (40,000 miles) beyond the moon so that their far-side probe would be able to communicate with Earth. Since the beginning of 2019, Chinese scientists have been exploring the moon’s dark side (which isn’t actually dark per se, but which is largely unknown to Earth’s inhabitants since the moon is tidally locked).
As the Chinese Yutu-2 rover was exploring terrain near the Von Kármán crater (a large impact site with a diameter of around 180 kilometers (110 miles)), the radio controlled vehicle found something interesting. The ground was covered in strange glistening green blobs which looked like something from H.G. Wells’ moon or from moon mission comic books of the 40s.
I couldn’t find a good photo, so I will use this fantasy illustration instead. Keen eyed viewers will spot salient geopolitical trends in the drawing.
Geologists and astrophysicists have been speculating as to the nature of these amorphous lumps (which stand out dramatically on the monochrome surface of the moon–not that that is evident in any of the photos I could find) and they now believe they have an explanation. The glossy lumps are probably a mixture of of pagioclase, iron-magnesium silicate, olivine and pyroxene. These minerals are known to be found on the moon thanks to NASA’s manned missions 5 decades ago. Speculation is that an intense impact melted them together into glass-like amorphous nodules of thesort which are foundin high energy events here on Earth (apologies to everyone who was hoping it was alien eggs or lunar bio-slime). There is still a mystery though: the regolith of the Von Kármán crater is not composed of these materials, so lunar scientists are still trying to understand where the glossy green rocks came from.
Astrophysicists have long speculated about the creation of the moon. Since the late twentieth century, the dominant theory has been “the giant impact hypothesis” which posits that a huge object about the size of Mars smashed into the newly coalesced Earth 4.5 billion years ago. Astronomers name this mysterious proto-planet “Theia” after the titan who was the mother of the moon is ancient Greek mythology. They speculate that the Earth and Theia melded together and the iron/heavy metal core of Theia sank into the molten Earth. A great deal of the light material was thrown into orbit around Earth where it coalesced into two moons (the smaller of which was unstable and pancaked into the dark side of the moon a few million years after formation).
These are pretty intense ideas, however they explain many of the features of the moon and Earth (you can look at a comprehensive list on Wikipedia if you like). Yet astrophysicists have not been completely satisfied by the current model of the giant impact hypothesis. The composition of the moon is suspiciously identical to that of Earth (whereas, computer models seem to indicate that it should contain more of Theia).
This week, a scientific paper suggests that the collision was somewhat different than envisioned in the giant impact hypothesis. The paper’s main author is Natsuki Hosono, and he has a revised version of how Theia hit Earth. According to this new hypothesis, the freshly formed Earth was still piping hot and its surface was covered with a lava ocean. Theia banged into Earth and careened off into space like a pool ball but the impact knocked the liquid ocean of lava into space, where it coalesced into one or two moons (which then ultimately amalgamated together). The new hypothesis answers critical questions about lunar composition (and about the ratios of volatile elements on the moon). Yet it does tend to beg questions such as what happened to Theia and what the nature of the Earth’s lava ocean was.
I guess we’ll keep watching the sky and the news to see how the world astronomy community reacts to the revised hypothesis. In the mean time I will see what I can dig up concerning Theia (the goddess or the proto-planet). That seems like the most intriguing part of the story yet details are weirdly exiguous.
We are living in a glorious new era of super marketing. Usually the results of this are rather hideous: our livelihoods are hostage to “keyword position metrics” and “analytic toolbars”. Every day the press is filled with histrionic drivel about threats which are statistically unlikely to hurt us (but which clearly drive hits). Yet there is a silver lining of a sort: in order to keep people’s attention, quotidian phenomena are being lavished with grandiloquent new names (or old poetic names which have been rediscovered and given new prominence). Speaking of which, don’t forget to check out tonight’s spring equinox super worm moon!
These days, the full moon on each month is given a sobriquet which is reputedly derived from ancient Native American lore. Here is a table of these names:
January: Wolf moon
February: Snow Moon
March: Worm Moon
April: Pink Moon
May: Flower Moon
June: Strawberry Moon
July: Buck Moon
August: Sturgeon Moon
September: Corn Moon
October: Hunter’s Moon
November: Beaver Moon
December: Cold Moon
Now I don’t remember any of this from when I was growing up (although this is possibly because I was playing Pacman rather than hunting migratory elk). The first time I remember hearing anything like this was in Disney’s “Pocahontas”. Yet the names have an obvious and evocative allure which speak to ancient annual rhythms.
The “Worm Moon” of March is called that because the ground softens and worms start to appear (although, come to think of it, the pinkish brown earthworms we all know so well are actually comparatively recent Eurasian invaders), but I like to imagine that it is the WORM moon when Lord Nergal, the God of Pestilence decides whether to winnow the overpopulated Earth. Or perhaps it is the Wyrm Moon, when dragons come out of their winter eyries in the south and fly off to their accustomed fantasy realms…
Ahem. At any rate, tonight marks an unusual occasion when the vernal equinox occurs at the same time the moon is full and at its perigee. This will be the final super moon of 2019 so go outside and enjoy it while you drink traditional spring spirits and discuss beautiful nomenclature.
Did you know it has been 30 years since a spacecraft swung by Neptune? Voyager II was the first and last spacecraft to visit the strange ice world which (with the demotion of Pluto) is the outermost planet of our solar system. A ball of gas, ice, rock and iron 17 times the size of Earth, Neptune is the third most massive planet and is the most dense of all the giant planets. However we know surprisingly little about this distant neighbor–a fact which was vividly demonstrated this week when astronomers discovered an unexpected new moon orbiting the planet. This new moon brings the tally of Neptune’s moons to 14. Mark Showalter, a researcher at the SETI institute in California, discovered the little satellite accidentally, while working on another project and the new body was confirmed with the Hubble Space telescope (which is also still out there, by the way).
Neptune’s largest moon is the retrograde Triton. The second largest moon is Proteus, an irregular polyhedron with a diameter of 420 kilometers, named after the shape-shifting old man of the sea. The new moon, which is named “Hippocamp”, after a seahorse like Greek sea monster (above) has a diameter of about 20 kilometers (about the length of Manhattan) and seems to have been formed from ejecta left over from when some primordial body slammed into Proteus.
Astronomers have spent comparatively little time studying Uranus and Neptune compared to the other planets of the solar system–which is somewhat ironic since most of the exoplanets we are finding are ice giants. It seems like they might be noticing this gap in their knowledge. A new mission to the ice giants is the third top mission priority in a vote-based ranking of proposed probe missions (by astrophysicists…nobody asked me what I want *cough* balloon mission to Venus’ atmosphere). Hopefully we will get our act together and launch a modern robot out to the big blue ice worlds in the not-too-distant future.
What with all of the holiday excitement, we have failed to compliment the Chinese Space Program on their successful lunar landing. On January 3rd, 2019, the Chang’e IV spacecraft landed on the South Pole-Aitken Basin, on the far side of the Moon, and deployed the Yutu-2 Rover. Here is a stunning photo taken by the rover as it began its explorations of the lunar surface. The spacecraft is, of course, named after the beautiful and sad Chinese moon goddess, Chang’e.
To quote the Smithsonian magazine, “[the Chinese lander will] collect mineral and geological samples of the moon’s surface as well as investigate the impact of solar wind on the moon. The craft even has its own little farm, or lunar biosphere, aboard—the first of its kind.” This miniature ecosystem consists of some potatoes, a few Arabidopsis plants (this is a hardy and universally known laboratory plant), and some living silkworm eggs in a special 3-kilogram (6.6-pound) aluminum terrarium (or lunarium?).
I realized as I write this that I don’t even know the Chinese Space Agency’s name. It turns out it is the Chinese National Space Administration “CNSA.” Their logo, immediately above, is a flying blue chevron with, I don’t know, blue wheat, or something–it looks like somebody mimeographed the Federation logo. But who cares about their logo? [cough, Chinese space administrators, you could hire a graphic artist to make a space phoenix, a rocket tiger, or galactic dragon or something for about ¥150.00 and outshine everyone before you even leave the pad]. The CNSA are now doing things which have never been done. This is the first landing on the dark side of the moon (which is not really dark, but which goes by that conceit since the moon is tidally locked).
United States triumphalism over our amazing moon program has obscured the fact that the first moon landing happened 50 years ago. Nobody has been on the moon during my lifetime, and I am not young. NASA has responded to budget cuts and whiplash conflicting demands from different presidential administrations by concentrating on robot probes of the unknown edges of the solar system. That is smart, practical, and amazing. Yet some of the thrill and prestige that NASA had even during its silver age in the eighties and nineties is now wearing away.
Of course America doesn’t even really have a functioning government right now, so perhaps it is better that we have decided to abandon our own bright dreams of moon bases and Mars missions…but it saddens me that we are so politically deadlocked that we are not pushing harder to explore and build in space. All day, every day, billionaires tell us how scarce resources are and how much better the private sector is at allocating these precious resources (to super yachts, offshore bank accounts, and regulatory capture, apparently). Well, resources are not scarce in space. There is infinite real estate. There are whole planets worth of matter. There are wells of energy which create all of the energy humankind has ever used throughout all of our history within a picosecond. Hopefully the brand new accomplishments of CNSA will remind the American people of our true nature–as scientists, explorers, and visionaries. However if we are too fixated on the crimes and inanities of Individual Number 1 to pay attention to the universe, maybe the Chinese can build a floating colony on Venus. I, for one, am looking forward to seeing what they have planned next.
ferrebeekeeper 