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During the last several years one of the most exciting aspects of astronomy has been data from two orbiting space observatories concerning planets which lie outside our solar system. The NASA space telescope Kepler discovers such planets by simultaneously measuring the light from thousands of stars for the faint dimming that occurs when a planet passes between the star and Kepler. The French satellite COROT (“COnvection ROtation and planetary Transits”) finds exoplanets by tracking the slight oscillations in distant stars caused by the gravitational tug of orbiting planets. The subtlety and elegant precision of both methods is astounding.
Sadly such astonishing engineering seems to have been near the edge of our technological abilities. Yesterday Kepler went into safe mode (a sort of automatic shut-down triggered by a crisis). Apparently a reaction wheel (a flywheel used to orient the spacecraft in relation to the stars) failed and Kepler can no longer be aimed properly. The orbital observatory initially had four reaction wheels—one of which was a spare– however the spare wheel failed in July of 2012 and at least three wheels are required to operate the satellite. If NASA cannot somehow reactivate the flywheel, then the mission is over.
Likewise on November 2, COROT suffered from a computer failure which made it impossible to collect data from the satellite and its status remains uncertain. Most likely it is offline forever. So our ability to find huge numbers of exoplanets via space observatory has temporarily been halted.
Kepler was launched in 2009 for a four year mission, however the mission was recently extended until 2016 (since it took longer to collect and make sense of the data then initially planned). At last count Kepler had discovered 132 planets and was monitoring more than 2,700 further candidate planet. As of November 2011, COROT had found 24 new worlds and was screening around 600 additional candidates for confirmation. Additionally two years of Kepler data has been downloaded but not yet interpreted so post-mortem discoveries may lie ahead.
It is frustrating that the age of almost daily discovery of new worlds has come to a temporary end due to equipment failure, however a new generation of planet finding missions is already on the drawing board. To quote The Guardian:
The European Space Agency announced last year that it would launch the Characterising Exoplanets Satellite (Cheops) in 2017 to study bright stars with known planets orbiting them. Nasa’s successor to Kepler will be the Transiting Exoplanet Survey Satellite (Tess), which will conduct a survey of planets around more than two million stars over the course of two years.
RIP Kepler and COROT, you discovered so many planets and you will be missed, but your successors will be even greater.
In the Roman pantheon, Janus is the two-faced god of beginnings, limits, doors, gateways, and departure. Unlike the other Greco-Roman deities, Janus was not imported from Greece to Rome. How he arrived in the Roman pantheon is unclear: some scholars believe that he was originally a gatekeeping deity of the near East while others argue he was an original Latin deity who was worshipped in Italy before Rome rose to power. Similarly there are different myths concerning his origin. The most dramatic tale of his creation asserts that he was made by Uranus, god of the primal heavens as a love present for dark Hecate. Janus despised being in the underworld so he escaped from Hecate by diving into the river Styx and swimming to the world above.
After fleeing the underworld, Janus acted as one of the earliest kings of Rome in the golden era when the titans ruled the world, however at the end of the titanomachy—the epic war between titans and Olympians—he made the poor decision to give shelter to Saturn, hated father of Jupiter. Jove was furious at Janus because of this betrayal and he cursed him with immobility and with a second face. Thereafter Janus stood at the threshold of heaven to open and close the gate as Jupiter came and went.
Janus was a popular god for the Romans and they worshipped him whenever they started a new venture or embarked on a trip. January is named after the god and the first day of every month is dedicated to him. The ancient temple of Janus stood in the center of Rome was open during war and closed during times of peace. Since the Romans were a warlike people the temple was rarely closed and sometimes stood open for hundreds of years at a time.
Behold Aplysia californica–an extremely large sea slug which grazes on red algae along the California coast. The mollusk is rarely found at depths deeper than 20 meters. It grows to seventy-five cm (thirty inches) in length and weighs a whopping 7kg (15.4 lbs). Aplysia californica belongs to a family of sea slugs known as the sea hares –so called because the two rhinophores (smelling organs) atop the creatures’ heads are fancifully said to resemble a rabbit’s ears.
Although this Pacific gastropod is interesting in its own right, the slug is of greatest importance to humankind as a research animal (like the regenerating axolotl). Aplysia has only 20,000 neuron cells–as opposed to a human brain which contains between ten and a hundred billion–and the slug’s neurons are extremely large. This allows neuroscientists to easily observe and assess physiological and molecular changes which take place in the cells when the slug learns something. Aplysia research is thus at the cutting edge of neuroscience. Nearly everything we know about the molecular basis of memory and learning started out as research with the humble gastropod.
A news piece on CNN today featured Dr. Eric Kandel of Columbia University who won the 2000 Nobel Prize in Medicine & Physiology for neural research (mainly on these slugs) and made immense headway on what is probably the great cellular biology mystery of our time. It is a pleasure to see a science article on CNN online but it was also somewhat dismaying to see how many comments were basically “why are we wasting money on studying slugs?” In case it is not self-evident why we are trying to discover the fundamental molecular mechanisms of memory and cognition, here is a brief and not-at-all comprehensive list.
Understanding these underlying biological processes would probably help us find therapy for neuro-degenerative disorders (such as Parkinson’s disease, multiple sclerosis, and Alzheimer’s disease). It might also allow us to comprehend a number of psychiatric conditions, such as schizophrenia and depression. At some point in the future, understanding the molecular basis of memories and thoughts might also allow for the engineering of some sort of bioimplant for the nervous system. You could learn Sanscrit by popping a chip in your head or record your nightmares via wire! Beyond such science fiction concepts, knowing about how the brain works is an end into itself—understanding the most complicated known structure in the universe is a necessary step to building structures of greater complexity.
Although perhaps the politically polemicized commenters who object to studying the sea hare actually reject the creature’s sex life–which is indeed somewhat at odds with traditional notions of romance and propriety.
Like all sea hares, Aplysia californica is a hermaphrodite with both male and female reproductive organs. Because of its physiology it can (and does!) use both sets of organs simultaneously during mating. Multiple Aplysia have been known to form chains of more than 20 animals (somewhat like pop beads) where each animal simultaneously acts as a male and female at the same time with its fore and aft partners. Copulation lasts for many hours (or sometimes for days). One can see how the creatures’ amorous predilections might not sit well with puritans and fundamentalists, however for providing a window into molecular neurophysiology we owe this gentle sea slug a big round of thanks.
My sincere apologies for being such a truant blogger last week! Not only did I fail to post any new articles since Tuesday, I unpardonably left you stuck with nothing but the flimsy Ms. Perry during that time. In order to apologize, allow me to take you on a trip to the island continent of Australia…15 million years ago during the Middle Miocene. During this time one of the largest birds ever lived across Australia: a giant fowl named Bullockornis.
Bullockornis was a 2.5 meter tall (8 foot 2 inch) gooselike bird. The creature weighed in at approximately 500 kilograms (1100 pounds) and scientists believe it was actually related to the modern geese and ducks. If you have ever met a modern goose, you will realize that a goose the size of a bear would be a formidable creature indeed. Additionally Bullockornis possessed a razor sharp beak with immensely powerful jaw muscles. It is hard not to imagine the giant bird nipping off a he-man’s arms like corn kernels or biting through bridge cables with this monstrous beak, but the truth is scientists don’t know what the bird used it for. The monstrous goose could have been a hunting carnivore (like certain ducks are today) or an herbivore which grazed on heavy dense plants. Perhaps, like contemporary geese, it was an omnivore which hunted, grazed, and opportunistically scavenged whatever it could get.
Bullockornis was discovered in 1979 but it only became well known when some PR savvy writer christened it the “Demon Duck of Doom” (which strike me as a silly 1930s Disney-style name, but I guess whatever gets people involved in paleontology is good). The scientific name “Bullockornis” means “bullock-bird” but, even though the bird was the size of an ox, it is actually named for Bullock Creek (a rich fossil location in the Northern Territory). Bullockornis was not the only giant of the Miocene in Australia. The Bullock Creek fossil beds also contained fossils of Giant horned tortoises, marsupial “lions” (i.e. thylacoleonids) and grazing Diprotodontids—giant wombats (although nothing so large as the mighty Diprotodon which evolved in the Pleistocene).
I am sorry it has come to this. I have to write an article for Star Magazine about Elvis movies—a task which requires me to watch all 31 Elvis movies in a short amount of time. Naturally I’ll write a post about the, um, insights into celebrity, aesthetics, and the national character which the experience has afforded me. However, at the moment, I am neck deep in go-go girls, guitars, and musical routines about water skiing. Today, therefore, I am simply posting a photo of contemporary pop princess Katy Perry wearing a beautiful crown and a Byzantine-themed Dolce & Gabbana gown at the 2013 Met Gala. I am sorry to do this to you (and I am stunned that Miss Perry has somehow sneaked into my blog by putting on a crown a second time). I will shamefacedly admit that she looks very beautiful and Byzantine in her jewels and beadwork. This year’s fashion theme at the Met Gala was “punk” and anyone who regards Byzantine royalty as fitting into that criteria cannot be wholly bad (maugre the gossip evidence).
Gamma rays have the most energy of any wave in the electromagnetic spectrum (which includes more familiar radiation such as x-rays, radio, and visible light). The wavelength of gamma rays (10 picometers and smaller–which is a subatomic scale) is less than that of any other sort of EM radiation. Such radiation is created in the event horizons of massive black holes and during the destruction of gigantically massive stars. Comic book enthusiasts know gamma rays as the mysterious super force which created and empowers the incredible hulk, although actual cell biologists recognize gamma rays as ionizing radiation–supremely hazardous to living entities.
On Saturday, April 27, the Fermi Gamma-Ray Telescope (a NASA satellite which orbits around Earth) detected a sudden brilliant surge of gamma radiation from the collapse of a super massive star in a galaxy 3.6 billion light-years away. Gamma ray burst travel in vastly powerful beams which are very narrow–an effect which is a result of the shape of supernovae, as illustrated in the picture above. Our old friend Eta Carinae has probably exploded and produced such a burst by now. A gamma ray bust from a nearby Wolf–Rayet would probably fry away life on our planet if it were aimed directly at Earth, but such explosions are increasingly rare as the universe ages. Scientists can monitor gamma bursts from the edge of the universe (i.e. the distant past) but such a powerful event has never been monitored by our modern satellites and observatories from a middle range until now.
As the gamma ray burst fades (and the astronomy community begins to assess the initial data) other observatories will be on the lookout for the next wave of phenomena associated with the supernova. Most of the energy of a supernova explosion is believed to be dissipated as neutrinos (esoteric subatomic particles which react very little with physical matter in this universe). Fortunately humankind now possesses a sophisticated neutrino observatory on the South Pole where thousands of sensors are imbedded within a vast amount of Antarctic ice. In the rare cases where neutrinos interact with matter, they produce a cascade of charged particles which can emit Cherenkov radiation (familiar as the spooky blue glow in a nuclear reactor). Understanding the neutrino signature of such an event would potentially further our understanding of the physical parameters of existence.
Also, a luminous flash of less energetic radiation (x-rays, radio waves, light, and so forth) should be following the gamma ray burst. We understand these parts of supernovae better (since they are visible from many angles unlike the linear gamma ray bursts), but it should still be pretty–and round out our understanding of the full astronomical event.
Behold the moderately exciting crown of João VI! Crafted in 1817, the crown served as the sole royal crown of Portugal until a revolution in 1910 transformed that nation into a republic. Made by the Portuguese royal jeweler, the crown lacks gemstones and if crafted wholly of gold, silver, iron, and velvet. Eight half arches (which somewhat resemble octopus arms) meet at a monde (a globe like ball) surmounted by a cross. Although the crown may not be as exciting as more ancient or ostentatious royal regalia, it forms the central decoration of the Portuguese royal coat of arms (below) which is very exciting and strange. Two frowning spear-tongued wyverns hold up a shield (which is inexplicably wearing a crucifix necklace). Upon the shield are seven castles and five smaller shields–each with a quincunx (five spots in an ancient Roman pattern). The whole thing is like some weird royalist arithmetic question.
Paolo Porpora (1617–1673) was a Neapolitan painter during the Late Baroque. He was apparently influenced by Dutch still life paintings and his works share the precision, control, and aesthetic elements of paintings by Rachel Ruysch or Balthasar van der Ast. Yet Porpora did not paint still life paintings. His works are miniature nature tableaus which have the dark drama of Baroque art written small in the lives of small animals. In Still Life with a Snake, Frogs and a Tortoise, the various reptiles and amphibians square off in a little landscape of fungi and flowers. The small world has the menace and violence of a Webster play as the cold blooded creatures stare beadily at each other attempting to work out who will eat whom.