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After posts about giant hornets which can dissolve flesh with their stings, a huge asteroid passing by Earth, and a mass cemetery in New York City, it is hard to know what to write about next… Thankfully, astronomers are way ahead of me! This week featured the announcement that scientists have discovered a black hole “right in our backyard.”
Fortunately, what counts as our backyard to astronomers is not really our backyard by any quotidian definition. Located in the southern constellation Telescopium, the newfound black hole is 1,000 light-years away: although it is the closest black hole to Earth discovered thus far, it is still 9.5 quadrillion kilometers away (5.88 quadrillion miles). We probably won’t blunder into it by accident when we sneak downstairs for a midnight snack.
Black holes, as you know, are deformed patches of spacetime where gravity is so strong that all proximate matter and electronic radiation (like light) are pulled into the gravity well. Black holes form when exceedingly massive stars collapse at the end of their life cycle: they become more massive as additional matter accretes into them. For example the supermassive black hole at the center of the galaxy is believed to have the mass of 431 million suns!
The black hole’s orbit in the star system is marked in red
The newly discovered Telescopium black hole is nothing like that though. Scientists estimate its mass to be mere 4 to 5 times that of the sun. Astronomers were able to discover the object only because the other two stars in its solar system (which they were studying in order to better understand binary stars) were not orbiting each other in a comprehensible fashion. Some massive third party was implicated…yet nothing was visible. Ergo, a black hole. There are believed to be hundreds of millions or even billions of these invisible horrifying objects in our galaxy alone, but they are nearly impossible to find unless there are nearby objects for them to interact with (yet which have not been slurped down into the ravenous maw).
I wonder where the actual closest black hole to Earth is located? Maybe we don’t really want to find out…
Messier 87 (M87) Galaxy
Messier 87 is a strange and extraordinary galaxy. For one thing it was discovered and named in 1781…even though the nature of galaxies (and the fact that there are more than one such “island universes” was not understood until 1923). Messier 87 was discovered by the great Charles Messier who was cataloging weird celestial blobs that could confuse comet hunters. The galaxy lies near the center of the Virgo supercluster of which our own lovely (albeit provincial) galaxy, the Milky Way, is a part. Formed by the merger of multiple galaxies, M87 is huge and contains more than a trillion stars–4 times the number of stars in the Milky Way. Additionally M87 is surrounded by more than 12,000 globular clusters (the Milky Way has perhaps 200 of these miniature satellite galaxies). Whereas the spiral Milky Way is “blue and new” with ample quantities of hydrogen to form new stars, the globular Messier 87 is “red and dead”: new star formation has slowed and the great elipsoid mass of stars is slowly dying (insomuch as galaxies can be said to live to begin with). The stars visible now are mostly middle aged main sequence stars or tiny long-lived red dwarves (tiny for stars…still not something you could pick up and put in your hatchback).
47 million year old Adapidae fossil from Germany
Messier87 is approximately 53 million light years away. The light that we can observe from it today originated during the Eocene, when the first little primates evolved on Earth and those photons have been streaking toward us through the great emptiness at 300,000 kilometers per second since when our direct ancestors were anxious lemur-squirrel guys staring pensively up at the stars.
A artist’s conception of such a black hole
The center of this monstrous astronomical entity is a supermassive black hole 6.5 billion times the mass of the sun (for reference, the sun is 333,000 times the mass of Earth–so this black hole has the mass of 2,164,500,000,000,000 Earths). A horrifying & beautiful relativistic jet of ionised matter 1.5 kiloparsecs (5000 light years) long is emerging from the black hole.
Why do I bring this up? Because we photographed the black hole! This is the first time we have accomplished such a feat. You can read about the esoteric details of how astronomers achieved such a thing by clicking on today’s Google Doodle (so I guess today’s blog post will not be a completely original/unique subject), I suspect you have seen the picture already. Yet even the eye-of-Sauron glory of this image (which was taken by a pan-global network of radio telescopes) does not exactly capture the scale of the black hole. My imagination is equiped for may things, but is not really much good for processing numbers bigger than a few thousand. The diameter of this black hole is roughly approximate to the orbit of Uranus and it has the mass of a small galaxy. So I guess keep that in mind when looking at the little orange eye. Now I am going to go lie down and hold my pet cat.
Etruscan Shrew (Suncus etruscus)
Alright, this is a little bit of a stretch for Etruscan week, but the Etruscan shrew (Suncus etruscus) is fascinating! It is the smallest mammal by mass weighing an average of only 1.8 grams (0.063 oz) (although there are certain bats with smaller skulls). The tiny creature does indeed live in what was once Etruria…although it admittedly also lives around the Mediterranean, throughout the Middle East, North Africa, Asia Minor, across Southeast Asia, and down into Malaysia. There are also invasive colonies in Nigeria (though goodness knows how they got there).
Etruscan Shrew Range
The shrew has a fierce metabolism: its little heart beats 1511 times per minute (25 beats a second). It must eat up to twice its own body weight every day to stoke its internal fires. I like food–but I would wear down fast eating a thousand hamburgers a day. Once I watched a documentary about the top ten super predators—and shrews weighed in at number one. They only eat live food which they catch—and they catch between 20 and 30 prey animals a day. This becomes all the more impressive when one considers that they eat insects (which have wings and are sometimes bigger than the shrew) as well as spiders and myriapods which are armed with terrible stings and venoms. Additionally the shrew dines on immature amphibians, baby rodents, worms, and larvae.
Etruscan Shrew with Snail
Etruscan shrews are largely nocturnal and crepuscular. Because of their poor eyesight, they have acute hearing, highly sensitive whiskers, and an amazing sense of smell: indeed, their long tin noses are mobile and can move about quite sinuously. In winter their fur grows long and they sometimes undergo periods of temporary hibernation when their body temperature drops down to 12 °C (54 °F). They are only social during mating season when a pair will live together through the 27-28 day gestation and until the cubs are independent (which is when they are three to four weeks of age). Litters range from two to six cubs. Because they are so small (and so widespread), Etruscan shrews are preyed on by all manner of snakes, cats, lizards, birds, and other predators. Their particular bane seems to be owls. Naturally, none of these predators are as dangerous to the overall species as humankind is. Etruscan shrews now have a non-contiguous range because of agriculture and habitat loss (although they seem to enjoy human ruins). They live to two years of age in captivity—although owls usually prevent death from old age in the wild.
The Etruscan Shrew is cute in its own way…
If we were not so jaded, we would recognize how remarkable and intense the Etruscan shrew is. Just writing about it, I feel like I have been describing an alien lifeform—a clever cunning creature which fits in a teaspoon. Except when it hibernates, it must endlessly devour. We will return to the art and society of ancient Etruria tomorrow, but right now spare a moment to reflect on the extraordinary nature of our strange mammal kin!
Between giant planets and small stars exists a bizarre class of heavenly objects known as brown dwarfs. Brown dwarfs are not massive enough to fuse hydrogen elements together as do main sequence stars like the sun, however brown dwarfs larger than 13 Jovian masses are believed to fuse deuterium atoms and large brown dwarfs (65 Jovian masses and up) are believed to fuse lithium. Since brown dwarfs can be very much like planets or like stars, there is a specific definition to describe the objects: a brown dwarf must have experienced some sort of nuclear fusion as a result of mass and temperature, however it cannot have fused all of its lithium (or it is considered a star or stellar fragment). A stellar physicist reading this blog might object that medium and large stars have some lithium present in their outer atmosphere, or that a very young white dwarf could still have some unused lithium present, or even that an old heavy brown dwarf could have fused all of its lithium. That physicist would be correct: she deserves some cookies and a pat on the head for poking holes in unnecessarily simple definitions.
Various Classifications of Brown Dwarfs
Brown dwarfs were theorized to exist in the 1960s, but no astronomer managed to discover one until 1988 when a team of University of California astronomers who were studying white dwarfs found a bizarrely cool red spectral signature for a faint companion to the star GD 165. Since then many brown dwarfs have been discovered and sorted into the major types M, L, T, and Y. They occupy a strange ambiguous area at the bottom of the Hertzsprung-Russell diagram—objects which are luminous and massive in comparison to everything else but tiny and dim compared to real stars.
There are some planets which are known to orbit brown dwarfs and there also brown dwarfs known to orbit true stars. It is beginning to seem that there a great many brown dwarfs out there: perhaps they are as numerous as true stars (or maybe they are even more common than that). Since they are hard to detect, scientists do not have a very accurate assay of their frequency in the universe. The question bears somewhat on our understanding of the universe–since a great deal of matter is not accounted for.
An artist’s conception of a brown dwarf seem from a closely orbiting planet
My mind keeps returning to the fact that some brown dwarfs have planetary systems. Imagine these melancholic twilight ice worlds forever orbiting a dim glow which will never blaze into a true sun. It is a melancholy picture, but not without a certain beauty.
A Brown Dwarf with Planet and Moon (painting by Lynette Cook from fineartamerica.com)
One of the ongoing horror stories from when I was in middle school was the invasion of the Africanized killer bees. In retrospect, it all sounds like a xenophobic horror movie from the 1950s, but people were truly alarmed back in the 80s. There were sensationalist news stories featuring the death of children and animated maps of the killer bees spreading unstoppably across America. The narrative was that mad scientists in South America had hybridized super-aggressive African bees with European bees in an attempt to create superbees (better able to survive in the tropics and produce more honey). These “Africanized” bees then escaped and started heading north, killing innocent humans and devastating local hives as they invaded.
An animated map of the spread of killer bees (uploaded to Wikipedia by uploaded by Huw Powell)
The amazing thing about this story is that it is all true. In the 1950s a biologist named Warwick E. Kerr imported 26 queen bees (of subspecies Apis mellifera scutellata) from the Great Lakes area of Africa to Brazil. A replacement beekeeper allowed the queens to escape in 1957 and they began to interbreed with local bees (of the European subspecies Apis mellifera ligustica and Apis mellifera iberiensis). The resulting hybridized bees were indeed better able to survive the tropics and quicker to reproduce, but they were also more defensive of their hives, more inclined to sting, and more likely to swarm (i.e. get together in a big angry cloud and fly off somewhere else when they felt unhappy). The killer bees (for want of a better term) could more readily live like wild bees in ground cavities and hollow trees. The hybrid bees out-competed local honeybees and spread across the continent. Sometimes aggressive queens would enter domestic hives and kill the old queen and take over!
Don’t make her angry!
Although Ancient Egypt may have been an early adapter of apiculture, Sub Saharan African societies did not practice beekeeping but hewed to the ancient tradition of bee-robbing. The African subspecies of honeybees came from a more challenging environment than the European subspecies. Forced to contend with deep droughts and fiendish predators (like the infamously stubborn honey badger), the bees are more defensive and more mobile than their northern counterparts. Apis mellifera scutellata is famous for not backing down from raiders but instead stinging them with dogged determination until the intruder flees far from their hive. This has led to unfortunate instances of children, infirm adults, and people with bee allergies falling down and being stung to death (which sounds like a really bad end) by the American hybrid. The sting of an Africanized bee is no more puissant than that of a European honeybee (and it also results in the death of the bee) but dozens—or hundreds—of stings can add up to kill a healthy adult.
(largely) satiric
The entire Africanized bee event was really a case of anti-domestication. Imagine if everyone’s dogs were suddenly replaced by wolves or if placid white-and-black cows were supplanted by ravening aurochs. If you follow that bizarre thought to its logical conclusion, you will anticipate what actually happened. Although initially dismayed, Brazilian beekeepers began to discover more placid strains of Africanized bees and started to redomesticate them. The hybrid bees do indeed produce more honey, survive droughts better, and it is believed they have a greater resistance to the dreaded colony collapse sweeping through honey bee population. Perhaps in the fullness of time we will learn to love the infamous killer bees.
Africanized “friend” bee?
Ferrebeekeeper has already posted about the aegis, the invulnerable shield of Jupiter/Zeus, which was fashioned by the king of the gods from the skin of his foster mother (and loaned to his favorite daughter. However the concept of Jupiter’s shield has a larger significance.
Yesterday morning, an unknown object appears to have slammed into the planet Jupiter. Oregon based astronomer Dan Petersen was watching the gas giant at 4:35 AM PST (September 10th, 2012) when a bright flash erupted from near the Jovian equator. Another amateur astronomer, George Hall of Dallas, TX was filming the planet through his 12 inch telescope and recorded the flash (you can see the video here).
The September 10th, 2012 Flash on Jupiter (recorded by George Hall)
Thanks to the florid nature of science fiction entertainment, it is easy to imagine scaly green Guarillions testing out energy weapons against the huge planet, but the flash was almost certainly from a comet or asteroid striking the surface (we will know more as astronomers look at Jupiter this week). Such impacts have proven to be much more common than imagined.
Jupiter has a mass of approximately 1.9 x 1027 kg (which is equivalent to 318 Earths). The gas giant is 2.5 times more massive than all of the rest of the non-sun objects in the solar system added together. The sun itself comprises between 99.8% and 99.9% of the mass of the system (which should put some perspective on the precision required for our ongoing programs to scan the nearby galaxy for exoplanets).
Jupiter Relative to the Sun and the Earth (NASA Goddard Space Flight Center)
The huge mass of Jupiter (relative to other planets and moons) means that a great many asteroids, comets, meteors, and whatnot fall into its gravity well. Were it not for Jupiter, these hazardous leftovers would otherwise fly all around the solar system willy-nilly knocking holes in things and creating unsafe conditions (just ask the poor dinosaurs about this). The ancient myths of the Aegis provide a powerful metaphor for this protection. Jupiter does indeed provide a shield for the smaller planets: If it did not suck up so many cosmic punches, who knows if life could even have survived?
(Lithograph by F. Heppenheimer)
Years ago, when I first moved to New York and was a bright optimistic young person, I would travel around the city via subway. Every day I entered and left the same entrance to the same underground train stop. One day somebody dropped a bag of cheap glitter stars right by the exit. These stars were different colors and different shapes. They started as a glittering clump at the top of the stairs but thanks to foot traffic and weather, they quickly got everywhere. Blocks away one would come upon glistening stars dotted along the sidewalk.
Then the stars began to fade and deteriorate. Their shininess wore off in the rain. Their arms broke as people walked on them, but every once in a while you would see one that had caught in a protected location and survived. Eventually there were no glitter stars left at all, but I suppose that the stuff they are made out of—bits of plastic and metal foil—is still out there in a landfill, or running down through drains into the ocean, or just blowing in the wind.
I mention all of this because it is a poignant metaphor for the currently projected fate of the expanding universe. The ultimate destiny of the universe was once a problem relegated to theologians and mystics (and crazy people). However, when cosmologists fathomed how the universe began–with the big bang 13 plus billion years ago–the question of how the universe would end became a legitimate scientific topic. Edwin Hubble’s discovery that the universe was expanding provided an ominous hint as to the ending.
The way the universe will end is contingent on whether the momentum of the universe’s expansion is greater than the force of gravity (which in turn depends on the amount of matter in the universe and the density of that matter). The current scientific consensus–based on carefully considered estimates of the universe’s mass density and on the most recently observed rate of cosmic expansion—is that the universe will continue to expand indefinitely.
Physicists, astronomers, and cosmologists therefore now project a rather glum fate for everything that exists. The death of the universe is divided into 4 stages summarized below:
Stelliferous: (Now to 100 trillion years into the future) This is an era teaming with stars: great masses of matter coalesce together into stellar masses and begin fusing together and releasing all sorts of energy as they do so. Bit by bit though the brightest stars will wink out and only long-lived red dwarfs will remain.
Degenerate (100 trillion to 1037 years in the future) After even the red dwarfs fade into darkness, most of the universe’s mass will remain in the dying husks of stars, or in the remains of more exotic stellar death (black holes left by the destruction of super massive stars, neutron stars, and white dwarfs). Electromagnetic energy in the Degenerate era will be generated by particle annihilation and proton decay rather than stellar fusion.
Black Hole Era (1038 to 10100 years into the future) After protons all decay away from the universe, the only large objects creating energy will be black holes which will themselves slowly evaporate into exotic matter over a vast expanse of empty time.
Dark Era (10100 years into the future to eternity) Protons and black holes will be gone and only the effluvia radiation from their passing will still exists in the universe. All that remains will be photons of immense wavelength, neutrinos, positrons, and electrons–sad burned-out remnants which lack any order or meaning. The universe will be incredibly vast, a horrible dark cold broken thing and it will remain that way forever.
So there you have it. The fate of the universe is to slowly freeze and decay over trillions and trillions of years and then dissipate away into dark nothingness over eternity.
Of course 10100 years is a very long time indeed. There is still plenty of time for beach parties and flower gardening, but this is not the end I would have wanted for anything I esteem as much as the universe. There isn’t much I can do about it though, except to hope that some unknown aspect of the cosmos provides a more spectacular and fiery end or that Vishnu intervenes. Or maybe there is a multiverse in which our cosmos floats like an abstract bubble: in the past, every time we thought we understood the universe it turned out that we were only looking at a small part of a greater whole. It wouldn’t surprise me if something still eludes us.
"Vishnu, you out there buddy? Some help?"
