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The Fourth of July was on a perfect summer Sunday this year and we failed to celebrate with a gallery of images. Therefore, in a belated salute to our great-but-troubled union, here are some of the all-time best photographs taken from the Hubble Space telescope, the world’s premier orbital telescope, Hubble launched in April 24, 1990 and has provided an astonishing window on the universe since then (despite some glitches which have cropped up from time to time), however now both the main computer and the backup computer are malfunctioning.
Hubble was designed to be periodically serviced by a space shuttle and its friendly crew of astronauts, however, since the shuttles have been permanently retired, scientists are now stuck trying to fix the aging legacy systems from 400 kilometers away. Although there are various reset combinations left to try, some astronomers and technicians are starting to wonder if the Hubble era is coming to an end.
Although Hubble’s troubles are dominating space telescope news at the moment, it is no longer the only story. The long-delayed James Webb telescope is finally getting close to launching (blast-off is set for November). That scope is to Hubble, what Hubble was to its earth-bound predecessors (which is to say, it is orders of magnitude more powerful and sophisticated). We will be talking about Webb in November, but for right now let’s celebrate the warm summer nights with Hubble’s cosmic gallery of astonishing celestial fireworks.
I have lived in my neighborhood for a while now, but it is a place with a lot going on and so I am still constantly surprised to find that I live right next to railroads, department stores, cemeteries, or universities which I didn’t know existed for all of these years. This sort of thing doesn’t just happen in Brooklyn: it is true for the whole solar system. Astronomers just discovered the largest mega-structure in the Milky Way Galaxy, a swooping ribbon of hot gas and baby stars now known as “the Radcliffe Wave.” The wave begins 500 light-years below the Milky Way’s disk at a spot in the night sky around Orion, and runs through the constellations Taurus and Perseus to wind up near the constellation Cepheus (and 500 light years above the galactic plane).
The Radcliffe Wave is about 9,000 light-years in length–roughly a tenth the diameter of the galaxy–and is though to contain about 800 million stars (as a quick refresher, our own sun has a mass about 333,000 times that of Earth). Scientists have noticed pieces of the wave before, since it is a hot zone filled with tumultuous stellar nurseries where bright young stars emerge from vast clouds of gas, yet they did not realize it was a continuous ribbon.
The ribbon is relatively close to Earth, too. To quote João Alves, the co-author of the Nature article about the Radcliffe Wave, “The sun lies only 500 light-years from the wave at its closest point. It’s been right in front of our eyes all the time, but we couldn’t see it until now.” Five hundred light years is not exactly a drive to the strip mall (it is a distance of 4,730,000,000,000,000 kilometers!), but we have been through the Radcliffe Wave 13 million years ago and the solar system is projected to pass into it in again in another 13 million years.
Astronomers are interested in the wave, but they are even more interested in why is exists to begin with. Alves speculates that it was created in the same manner that ripples are made in the water of a pond when something exceedingly massive lands in it. What would be massive enough to make ripples in a galaxy? Another galaxy? Some sort of black hole biz? A giant hunk of dark matter? Who knows? (although this older post about giant voids in space might be somewhat instructive in talking about space’s busy neighborhoods too). We only just discovered the Radcliffe Wave and we will have to start working to figure out where it originated and what it means. After all, we will be there surfing it in a mere 13 million years. Kowabunga, space dudes!
Since the year is pretty new and my bright hopes and shining dreams for 2019 are still intact, here is a Friday evening blog post! I have been worried that I have not been devoting sufficient time to blogging. In particular I have lately been especially bad about responding in a timely fashion to anybody gracious enough to post a comment. I promise I will work hard on doing a better job writing and responding this year, so keep those comments coming! In the meantime, kindly find a picture of the first sculpture which I finished in 2019: “Galactic Fluke,” which is carved out of wood and adorned with a handmade polymer galaxy and plastic stars. When I pulled that galaxy out of the oven it looked like a millipede with hairy waving legs…and it was no picnic making it adhere properly to the fluke instead of to my fat fingers.
Regular readers of this blog will recognize the flounder as the quixotic avatar of all Earth life in my recent artworks. Concerned friends and relatives have asked why the Pleuronectiformes have so completely infiltrated my ouevre–so I will answer that question in greater depth in 2019 (the emotional side of the story involves a confessional story about my life, and the intellectual side of the story involves a treatise on environmentalism and musings about the future of all of humankind).
This sculpture however transcends such concerns–this is, after all, a galactic fluke…a very great flounder indeed! It represents the apogee of my desires–life transcendent and all-present at an incomprehensibly vast scale. One of my friends said that his mother, a devout Muslim, was worried that my art is idolatrous (!) which is difficult to respond to, but I do certainly try to imbue my conception of the numinous into my flounder works. I have never found a bunch of rules from ancient near-eastern sages to be particularly supernatural…but the interlocking destinies of lifeforms living together in complex ecosystems does inspire me with feelings of transcendent awe. The great web of life on Earth is the closest thing we know to divinity–save perhaps for the celestial grandeur of outer space with all of its scope and mystery. This small sculpture is an attempt to bring these two sacred concepts together in poplar, paint, and plastic.
Sometimes if you aren’t watching the heavens (or the news) closely enough, you miss a major astronomical discovery. For example last summer, astronomers discovered a galaxy which formed only one or two billion years after the Big Bang (so I guess it is unclear whethter I missed this story by one year or by 12 billion). At any rate, the galaxy hunters used the Hubble space telescope to peer through a powerful gravitational lense far away in space. Gravitational lenses are areas where timespace is warped like a huge lense by high-gravity phenomena, and a viewer can use them like a huge lense to see far-away objects. By using the Hubble telescope together with the gravitational lense they were able to see back a dozen billion years in time to the edge of the universe…as it once was not long after creation. What they saw perplexed them.
There is a fundamental difference between galaxies. Galaxies where stars are being formed tend to be blue and spiral shaped (like our own beloved Milky Way!). Galaxies where stars have largely stopped forming are “red and dead” since the remaining stars tend to be long lived red dwarf stars and the bright young (short-lived) blue stars are mostly gone. These red galaxies are not shaped like spirals, but tend to be elliptical shaped (like an egg or a football, not like one of those evil gym machines).
The ancient galaxy at the edge of the universe was neither of those colors or shapes. It was a dense yellow disk. Stars formed in an (enormous) accretion disk but then, for some reason, new star formation stopped. The blue stars burned out (“the light that shines twice as bright etc, etc..”), but the yellow middle aged stars were still burning. The galaxy had three times the mass of the Milky Way but scrunched into a pancake of much smaller area.
So do galaxies always form as disks and then either become self-renewing blue spirals (maybe by colliding with other galaxies or clouds of dust)or dead red footballs? Or was this early yellow disk galaxy an abberation? Or is our own galaxy truly new (well…newish…being only a few billion years old)? I do not understand astrophysics well enough to answer these questions or even formulate them properly (although I get the sense some of these questions may not yet be answered by anyone in any comprehensive way), but I would love to hear what people can add to this rudimentary yet compelling story of shapes and colors.
Hey, remember the super-massive black hole at the center of the galaxy? Well, scientists have been thinking about it too, and they concluded that other black holes should sink into the middle of the galaxy near to the central monster. To find out if this holds true, they utilized the Chandra X-Ray Observatory (an x-ray telescope located on a satellite in orbit around Earth) to observe stars near to the center of the galaxy. Black holes can’t be detected on their own, but if they interact with nearby stars they produce esoteric x-rays which can be detected (so long as the x-ray telescope is outside of a planetary atmosphere, which absorbs x-rays, thank goodness). Within the tiny (er, relatively tiny) three light year area which they scrutinized, the astronomers discovered dozens of black holes. Extrapolating this data leads them to conclude there are more than 10,000 black holes at the center of our galaxy. I wish I could contextualize this for you, but I just can’t… the concept of 10,000 super-dense gravity wells flattening and tearing all of the spacetime in the center of the galaxy into Swiss cheese is to disturbing for me to deal with (in any other way than blurting it out in a midnight blog). I’m not sure this universe is safe at all. I am going to go lie down.
Artist’s Concept of WISE J224607.57-052635.0
Ferrebeekeeper has featured some mind-bogglingly strange astronomic entities before—black holes, ultra-dense stellar remnants, hyper-giant stars with a million times the mass of the sun, colliding neutron stars—but today we move up to a vastly greater order of magnitude! Astronomers have just discovered a new class of galaxy which emits energy at unimaginable levels. Using NASA’s Wide-field Infrared Survey Explorer (WISE), scientists have discovered what are being tentatively called “extremely luminous infrared galaxies” (ELIRGs).
One of these galaxies (with the not-very-snappy designation “WISE J224607.57-052635.0”) is producing 10,000 times more energy than the Milky Way, despite being much smaller than our familiar home. The newly discovered galaxy is putting out more energy than 10 trillion suns (or, more correctly, I should say it was putting out the energy of ten trillion main-sequence yellow stars). Scientists consider it the brightest known galaxy in the universe.
WISE J224607.57-052635.0 is 12.5 billion light-years away. Since the universe is 13.8 billion years old, what we are now seeing dates to a whole different era of galactic dynamics. Today maybe WISE J224607.57-052635.0 is a burned-out remnant…or a perfectly respectable middle-aged galaxy like the Milky Way. Who knows? But twelve-and-a-half billion years ago it was releasing an inconceivable amount of energy—so much so that astronomers are having trouble adjusting their theories to it. Perhaps some embryonic galaxies have black holes which gobble up stars at a much greater rate than initially thought or, alternately, some unknown set of circumstances has allowed the black hole (or holes?) at the center of WISE J224607.57-052635.0 to somehow surpass the theoretical threshold of black hole feeding.
Clearly astronomers are going to be sorting out what exactly happened out there for quite a while, but in the meantime, when you look up at the night sky remember you are looking at an invisible fountain of energy ten trillion times brighter than the sun. [Ooh, I made myself dizzy]
Previously discovered dwarf satellite galaxies (in blue) and the newly discovered candidates (in red) (Yao-Yuan Mao, Ralf Kaehler, Risa Wechsler (KIPAC/SLAC))
We have some new galactic neighbors! Well, actually maybe “new” is not the right term: they have been there for a long time but we only just now noticed. Astronomers are reporting the discovery of nine dwarf satellite galaxies orbiting the Milky Way like remoras stuck to a cosmic shark. These nine miniature galaxies are additional to the well-known Large and Small Magellanic Clouds—two dwarf galaxies which are located right next to the Milky Way (being respectively 160,000 and 200,000 light years away).
The new dwarf galaxies were discovered by a team of astronomers poring over data recovered from the Dark Energy Survey (a super-high resolution digital array which is part of the Victor M Blanco telescope in the Andes). The closest is a mere 97,000 light years from the Milky Way whereas the farthest lies 1.2 million light years away from us. The dwarf galaxies are a billion times fainter than the Milky Way. They are made up of millions (or hundreds of millions or even billions) of stars but are insignificant in size compared to the hundreds of billions of stars which constitute a true galaxy. Scientists believe that there are hundreds of similar miniature galaxies and pseudo-galaxies near the Milky Way, but they are dark and difficult to find (comparitively speaking).
The Large and Small Magellanic Clouds, near which the satellites were found. (image from European Southern Observatory)
I have been saying “dwarf galaxies” because I like the way it sounds (like the new galaxies live together in the woods in a little hut and work in the mines!), but actually only three of the new companions are definitely dwarf galaxies. The remaining six structures may be dwarf galaxies or they may merely be globular clusters—a far less euphonic phrase which indicates a group of stars which orbits a galactic core as a satellite. Unlike globular clusters, dwarf galaxies are held together by the gravitational mass of large quantities of dark matter (um, assuming it actually exists). Indeed dwarf galaxies seem to contain far greater quantities of dark matter than actual galaxies. This makes the newly discovered galactic neighbors a potentially useful focus for studying the properties of dark matter and refining our model of the universe.
A strangely horrifying illustration of the supermassive black hole located in the middle of the very dense miniature galaxy M60-UCD1
Fifty million light years away from Earth is the dwarf galaxy M60-UCD1. This tiny globular galaxy is 300 light years across–whereas our own beloved spiral galaxy, the Milky Way, is 120,000 light years in diameter! Yet within that 300 million light year sphere, M60-UCD1 is a crazy place. Despite its (comparatively) tiny area, the dwarf galaxy is teaming with stars: astronomers estimate it contains 140 million star systems. If Earth were located in M60-UCDI, the night sky would positively glow with millions of visible tars (as opposed to the measly 4000 which are visible to the naked eye in our present location). This is all quite odd, yet only recently did astronomers discover the strangest thing about M60-UCDI. At the center of the tiny galaxy is a supermassive black hole which weighs more than twenty million suns. To quote the European Space Agency’s website, “The supermassive black hole at the centre of M60-UCD1 makes up a huge 15 percent of the galaxy’s total mass, and weighs five times that of the black hole at the center of the Milky Way.”
Messier 60 with M60-UCDI (Composite image from NASA’s Hubble & Chandra space telescopes)
Astronomers speculate that something went terribly wrong to form this oddball of a galaxy. A prime culprit is Messier 60, a large scary galaxy which lurks near the little dwarf galaxy. The black hole at the center of Messier 60 is 4.5 billion times the size of our Sun! Perhaps once upon a time M60-UCDI was a normal galaxy with billions of stars…till it wandered too close to Messier 60. The larger galaxy tore off the majority of the stars which made up M60-UCDI and added them to itself (while Messier 60’s black hole swallowed up its fair share of star systems). It is a horrifying image of galactic bullying! Why can’t we all get along?
A mosaic image taken by the Hubble Telescope of Messier 82 (NASA, ca. 2000)
Twelve million light years from Earth lies Messier 82, a starburst galaxy 5 times more luminous than the entire Milky Way galaxy. Messier 82 (AKA M82) is a very happening and dynamic galaxy: stars are being created there at an exceptionally high rate—most likely because the galaxy is “interacting” (or possibly colliding) with its neighboring galaxy M81. In 2005, the Hubble Space Telescope detected nearly 200 massive starburst clusters near M82’s center. Within these huge masses of dust and gas, stars are being birthed (and dying) at an astonishing rate. The high energy released by this cosmic upheaval is nearly constant and the outflow of charged particles from M82 is evocatively known as “superwind”.
Lovell Telescope, Jodrell Bank Observatory (Mike Peel; Jodrell Bank Centre for Astrophysics, University of Manchester)
In 2010, astronomers working at Jodrell Bank Observatory in England discovered a mystery at the heart of M82: an unknown object was emitting high energy electromagnetic radiation in a pattern unlike anything else so far observed in the universe. The mystery object appeared to be moving at 4 times the speed of light (which is, of course, quite impossible according to the standard model of the universe. Newscientist.com offered the following explanation (of sorts) for the mystery object’s perceived velocity:
Such apparent “superluminal” motion has been seen before in high-speed jets of material squirted out by some black holes. The stuff in these jets is moving towards us at a slight angle and travelling at a fair fraction of the speed of light, and the effects of relativity produce a kind of optical illusion that makes the motion appear superluminal.
At present, the best explanation astronomers have for the mystery is that it is some sort of microquasar or black hole which is interacting in an unusual way with the tumultuous mass within a starburst cluster. At present, the mystery is unexplained.
A super-dramatic before-and-after animation/photo of the type Ia supernova in M82
However, at present, M82 is doing entirely different things which have captured the attention of the international astronomy community. On January 21st, 2014, Steve Fossey and a group of his students at University College London spotted a colossal explosion within M82. The event was quickly identified as a type Ia supernova, a bright and consistently energetic star explosion which occurs in binary stars where at least one star is a white dwarf (the dead, but energetic fragment of a larger star). CBS News explains the phenomenon and its historical significance:
[When a] white dwarf siphons off too much mass from its companion star, a runaway nuclear reaction begins inside the dead star, leading to a brilliant supernova. Because Type Ia supernovas are believed to shine with equal brightness at their peaks, they are used as “standard candles” to measure distances the universe.
The supernova in M82 is the nearest supernova of its type observed since Supernova 1987A was spotted in February 1987 in the Large Magellanic Cloud (the dwarf galaxy which is companion to the Milky Way). Telescopes around Earth are turning towards Ursa Major (where M82 is located in the sky). Although the supernova is big news here, it is a very stale story in M82 where this all happened 12 million years ago.
An Artist’s Conception of a Type Ia Supernova
News of the cosmos frequently involves inconceivably large numbers or gigantic objects beyond human imagination. This is particularly true of galaxies–gigantic systems of stars, gas clouds, black holes, and exotic unknown dark matter. Even the tiniest dwarf galaxies have tens of millions of stars and our lovely home galaxy, the Milky Way, has approximately 300 billion star systems! However the universe is a mysterious place and it frequently refutes conventional wisdom and prior expectations. This week astronomers from Hawaii’s Keck Observatory announced that they had discovered a ridiculously little galaxy with only a thousand stars. The adorable miniature galaxy, which has been dubbed Segue 2 is not a star cluster because it is surrounded by its own halo of dark matter, but it is many orders of magnitude smaller than any known galaxy. Astronomers are trying to determine whether it is a scrap of a larger galaxy which was ripped apart (!) or whether it is a baby galaxy which never fully coalesced. Astronomers hope that by learning more about Segue 2 and other hypothesized tiny galaxies they can find out more about the creation of the universe and the formation of elements.
“NO!” –image editors
ferrebeekeeper 