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OK, yesterday I promised we would get to the space news. Clearly the real story is the earthlike planet right in our backyard (erm, relatively speaking). However it isn’t going anywhere right now so I am going to blog about it later when we have all had a moment to think about the real implications. The space story I am looking at today is closer to home, but still takes place out there in the black: back in October of 2014, NASA lost communication with Stereo B one of two paired spacecraft which orbited the sun from the distance of Earth.
The solar observatory spacecraft allow stereoscopic viewing of the sun. One spacecraft Stereo A was ahead of Earth on its orbit, whereas Stereo B trailed behind us. The two observatories allow us to study coronal mass ejections and other stellar phenomena. In 2011, the craft were 180 degrees apart from each other—allowing humankind to view the entire sun at once for the very first time (a truly remarkable milestone, when you think about it, which I heard nothing about at the time).
Sadly, however, in 2014, as part of an automation and attitude test, Stereo B began to spin. Mission controllers then lost contact with the craft which (because of the nature of its work) was on the other side of the sun! NASA has patiently waited till the orbital path of Stereo B carried it further towards Earth and has used the Deep Space Network, a networked array of radio telescopes to find the errant craft.
We are still working on figuring out what sort of shape the poor guy is in (and maybe rehabilitating the spinning observatory), however I feel the story is worth telling as a sort of reminder of the fleet of crafts we have up there, which we don’t think about very often.
An artist’s rendition of a solar sail spacecraft!
The Planetary Society is a club which believes we should spend more resources exploring space. I used to be a member back in the halcyon days when I could afford their annual dues, but alas, I have merely been following their exploits lately. Mostly they are a political action committee: they use their money to hire lobbyists to remind recalcitrant leaders of the many, many benefits of space exploration. Also they showcase celebrity explorers, scientists, and astronomers (or other famous folk) in order to popularize space research to the fickle and forgetful public.
Well, that’s what they do most of the time…Sometimes they spearhead astonishing James Bond schemes of their own. The most recent of these grand plans involved buying a converted Soviet ICBM and using it to launch a solar sail into outer space! Sadly (yet somehow predictably) the Russians sold the Society a dodgy bum missile which failed after a minute and a half of flight and exploded over the Arctic Ocean. This happened ten years ago, and despite the abysmal failure, I felt honored to be part of it! When did you last cooperate on a project which would make Blowfeld jealous? (I exempt mention of my tax dollars which go to NASA—you federal scientists are awesome and I want you to keep it up, but I am talking about a private club right now).
A Delta-class Submarine Firing a SS-N-18 (of the sort that failed)
Anyway I bring all of this up, because the Society has scraped together enough pocket change to try again (even without my annual $37.00 membership fee). In five days they are launching a test flight which will pave the way for a full-fledged solar sail launch in 2016! The Society learned certain things from the failure a decade ago, most notably “do not trust the Russians” (a lesson which is written upon the very landscapes of Eastern Europe and Central Asia to the extent that it is visible from space, but which was still somehow lost on the Planetary Society until they actually purchased an ICBM).
The Planetary Society’s LightSail spacecraft, with its four sails deployed, undergoing tests in Sept. 2014. Credit: Justin Foley/The Planetary Society.
This time they are buying aerospace capacity from more reputable sources—the US Air Force (for the upcoming test flight) and SpaceX for the full mission. I mention all of this in order to direct your attention to the test flight on May 20th (EDT) which Ferrebeekeeper will definitely revisit and to also point you toward the Kickstarter funding project for next year’s full fledge flight! If you have some money burning a hole in your pocket, you could always spend it launching a high tech sail the size of a New York apartment into space (well, maybe the actual spacecraft will be larger than that once it unfurls from its breadbox size cubesat). Aside from buying stunning original artwork, what could be a better use of your petty cash?
A Stellar Nursery in the Carina nebula: pillars of gas and dust three light years tall (NASA, JPL)
Stars develop in vast nebulae of swirling dust and gas that are light years across. Within these giant molecular clouds (GMCs), gravity gathers matter together into an accretion disk which then further compacts until the density and temperature of the central ball of gas reach the extremes necessary for nuclear fusion to begin. Different stars created in different GMCs thus have different spectrographic characteristics depending on the place of their creation, however GMCs tend to be inconceivably vast and multiple stars form in one stellar nursery at the same time. Such stars share similarities of composition.
The Sun
For a long time, astronomers have sought the stars which formed at the same time in the same GMC as our beloved sun (which is approximately four and a half billion years old). Now, at long last, it seems we have found one of the sun’s bigger sisters. A yellow star in the constellation Hercules seems to have the same composition as the sun. Using elaborate computer models of stellar drift, scientists have traced the star (which goes by the unlovely name “HD 162826”) and the sun back to the same place of origin. HD 162826 is 15% larger than the sun (which is why I called it a big sister) and although it does not have any “super Jupiter” type planets, there is a possibility it may have some small rocky inner worlds. The sun has grown somewhat distant from its sibling: during the billions of years since their creation the two stars have drifted 110 light years from each other.
HD 162826
The discovery was made by a team of astronomers from around the world (lead by Ivan Ramirez from the University of Texas). The sun’s sister is not visible to the naked eye, but no doubt many telescopes will be trained on Hercules to discover if there is anything we can learn from our sun’s long sundered nursery mate.
NASA has recently released plans for a new ion thruster capable of propelling spacecraft to the astonishing speed of 90,000 miles per hour (the thruster is named NEXT–an unnecessarily clever acronym which is short for “NASA’s Evolutionary Xenon Thruster”). Reading about the thruster’s blazing speed made me wonder: what exactly is the fastest human-made item ever? The answer was not what I expected—or rather it was exactly what I expected, but it happened a long time ago.
NASA’s Helios 2 spaceprobe
To escape Earth’s gravitational pull, an object must already be traveling around 25,000 mph, so ICBMs and orbital space craft are fairly speedy anyway. Interplanetary probes are the fastest objects we humans have crafted, although they tend to obtain their velocity by means of using the gravity wells of planets or the sun to “sling” off at a higher velocity. In 1976, NASA launched the solar probe Helios 2 to measure electromagnetic radiation emanating from the sun and to calculate solar magnetic fields. The eccentric orbit of Helios 2 resulted in the craft reaching a top speed of 157,078 miles per hour. If the probe were running along the equator, it could whip around the Earth six and a third times during an episode of “The Bionic Woman” (or whatever other hour-long show was playing in 1976).
We’re probing the sun and voting for Carter: apparently that’s what’s happening…
Helios 2 has held the record for being the fastest man-made object since I was a toddler, but NASA has finally decided to rise to the challenge (since nobody else apparently has the know-how or the desire to push mankind forward). Solar Probe Plus is a NASA mission planned for launch in 2018 which features a robot space probe which will travel to the outer corona of the sun (assuming feckless American lawmakers don’t scrap the mission). When the probe is closest to the sun it will be a mere 5.9 million kilometers (3.67 million miles) from the photosphere of the star and it will be traveling at a blistering 432,000 miles per hour. The insane temperature and radiation which Solar Probe Plus will face at such proximity to the sun will necessitate that the speed demon robot must take shelter behind a carbon fiber reinforced carbon shield as it blasts through the outer corona at a fifteen hundredths the speed of light (it turns out light is still incomprehensibly fast compared to our very fastest things).
An artist’s conception of Solar Probe Plus (Credit: JHU/APL)
(Coincidentally, long time readers might wonder why I have abandoned my usual convention of citing measurement values in metric and then following them with U.S. customary measurements in parenthesis. The answer, alas, is laziness. All of the sources about really fast things use miles per hour and I didn’t feel like converting. If you are so inclined, you can easily convert to kilometers per hour (or parsecs per second, or whatever) using the internet. Alternatively, you could write me an angry letter in French.)
A Pegasus Rocket launched from Orbital’s airplane “Stargazer”
Tonight Orbital Sciences Corporation is launching a Pegasus rocket from Vandenberg Airforce Base in California (which is a sentimental, um, missile base for me since my grandfather was a workman there back in the ‘50s). Orbital is one of those vaunted private companies which is reaching for space as the government defunds NASA, although, truth be told, the corporation seems to concentrate on launching satellites and building rockets for the government so it might not be too different from the classical aerospace companies which have been interwoven with the nation’s Space/Defense programs since back when grandpa was painting missile silos. The apex of Orbital’s ambition was to build a spaceplane to replace the space shuttle, but their proposal was not selected by NASA and they are winding down their efforts to build a crewed vehicle.
The IRIS solar observatory satellite (NASA)
Actually the Pegasus rocket is launched from a high altitude airplane which is launched from Vandenberg. This technology was developed during the cold war for interception (i.e. shooting down enemy spy satellites) but tonight it finds a higher calling: the rocket will be launching a small satellite named IRIS into orbit. IRIS stands for Interface Region Imaging Spectrograph. The satellite is a small ultraviolet solar observatory designed to study the mysterious chromosphere of the sun—the second of three layers of the sun’s atmosphere which, perplexingly, is much hotter than the region beneath it. You can look at this old post for a proposal about why this is so–the answer probably involves solar tornadoes (IRIS will be able to tell us if this solution is correct).
If you are turning in around 10:20- 10:30 EST you can watch the launch at this link (probably). Go IRIS! It’s exciting to have another robot spacecraft monitoring our star!
A day ago an international team of stellar physicists announced that the sun’s surface is covered with thousands of searing hot plasma super tornadoes each of which is the size of a large continent on Earth. Using a combination of a space telescope and a ground telescope, researchers discovered that each of these plasma vortexes spins at velocities up to 14,500 kilometers (9,000 miles) an hour.
(CREDIT: Wedemeyer-Böhm: Parts of the image produced with VAPOR)
The mystery of why the corona of the sun is 300 times hotter than the star’s surface has long vexed scientists. The surface of the sun is a balmy 5,526 degrees Celsius (9,980 Fahrenheit), while temperatures in the corona peaks 2 million degrees Celsius (3.5 million Fahrenheit). The discovery of these giant fast-moving storms provides a new mechanism by which heat is transferred through the sun’s atmosphere and ejected into the corona. Energy locked in the powerful magnetic vortexes is effectively self-insulated and does not heat the solar photosphere and chromosphere as much as the corona (where the storms widen and dissipate).
The Sun photographed by the Atmospheric Imaging Assembly (AIA 304) of NASA’s Solar Dynamics Observatory
Sven Wedemeyer-Böhm, a Norwegian scientist working on the team was quick to stress that the tornadoes are likely one of several complicated energy transfer mechanisms by which heat reaches the solar corona. However it seems that there are more than 11,000 of these huge plasma tornadoes on the solar surface at any given time.
Artist's Interpretation of Sedna (Credit: Gemini artwork by Jon Lomberg)
After the discovery of Pluto in 1930, there was a long hiatus in discovering objects of comparable size. Then in 2003, a team of astronomers led by Mike Brown of Caltech discovered a distant icy sphere which was quickly heralded as “the tenth planet.” Mike Brown announced the discovery on his website along with his team’s rationale for naming the object. He wrote “Our newly discovered object is the coldest most distant place known in the Solar System, so we feel it is appropriate to name it in honor of Sedna, the Inuit goddess of the sea, who is thought to live at the bottom of the frigid Arctic Ocean.
It turns out that Sedna is only one of many similar snowball-like planetoids beyond Neptune. In fact, Ferrebeekeeper has already described the dwarf planet Eris (named after the Greek goddess of Strife) which is the largest currently known Kuiper belt object. Sedna was the first to be discovered since Pluto and it sparked a debate about such objects which ultimately resulted in Pluto’s downgrade to dwarf planet. Sedna also has some unique features which make it remarkable in its own right.
The orbit of Sedna (red) set against the orbits of Jupiter (orange), Saturn (yellow), Uranus (green), Neptune (blue), and Pluto (purple)
Sedna takes 11,400 years to complete its orbit around the sun and its bizarre highly elliptical orbit has given rise to much conjecture among astronomers. Although some astronomers believe it was scattered into a skewed orbit by the gravitational influence of Neptune, other astronomers believe it originated in the inner Oort cloud and was never close enough to Neptune to be affected by the giant’s gravity. Some scientists speculate that its lengthy orbit may have been caused by a passing star (perhaps from the sun’s birth cluster). A few theorists have gone one step further and conjectured that Sedna is from a different solar system and was captured by our Sun billions of years ago. A final school contends that Sedna is evidence of an unknown giant planet somewhere in the depths of space (!).
A photo of Sedna taken from a powerful telescope on Earth
We don’t know much about Sedna except that is probably 1,200–1,600 km in diameter and that its surface is extremely red. After Mars, Sedna is one of the reddest astronomical objects in our solar system. This color comes from the profusion of tholins covering the methane and nitrogen ice of which the little world is formed. Tholins are large, complex organic molecules created by the interaction of ultraviolet light on methane and other simple hydrocarbons. It is believed that early Earth (prior to obtaining an oxidizing atmosphere) was rich in Tholins and they are one of the precursors to the rise of life.
Shamash was the Mesopotamian deity of the sun. To the Akkadians, Assyrians, and the Babylonians he was synonymous with justice, generosity, and salvation. However there was a second solar deity in the Mesopotamian pantheon, Nergal, who was not associated with such positive aspects of existence. Nergal was the child of Enlil, god of the wind, who was exiled from earth for raping Ninlin, the goddess of the open fields. Ninlin followed Enlil into exile and gave birth to their son Nergal in the underworld (Sumerian myth-makers should be ashamed of the sexism of this story). Nergal’s dark origins foreshadowed his nature. Unlike Shamash, who represented the life giving power of the sun and divine justice, Nergal was only associated with certain phases of the sun. To quote Wikipedia “Portrayed in hymns and myths as a god of war and pestilence, Nergal seems to represent the sun of noontime and of the summer solstice that brings destruction, high summer being the dead season in the Mesopotamian annual cycle.”
Akkadian Seal of Nergal with a sickle-sword and a mace with two feline heads (c. 2360–2180 BCE, carved from soapstone)
As a god of plague, drought, fire, and insufferable heat, Nergal quickly came to be associated with death and the underworld. He was portrayed either as a powerful man bearing a sickle-sword and a mace, or as a lion with a man’s head.
Although he was a terrible god of destruction, the main myth we have about Nergal is romantic in nature. Mesopotamian scholars have discovered and translated a poetic epic recounting Nergal’s tempestuous courtship of the dark goddess Ereshkigal (the queen of the underworld, who once gave Ishtar such a wretched time). After a passionate tryst, Nergal left Ereshkigal, who thereafter was overwhelmed by passionate longing for further intimacy. Hearing of her unhappiness and realizing how much he in turn missed her, Nergal abandoned his place in the heavens and traveled down through the seven gates of hell to rejoin Ereshkigal. The two death gods then shared a bed for seven days and seven nights before marrying and jointly sharing rule of the underworld (it’s a happy story!).
A modern painting of Nergal
Despite the felicity of his connubial circumstances, to the people of Mesopotamia, Nergal represented the unpredictability of mortal life and early unnatural death. He was worshiped, particularly at his chief temple located at Cuthah (a smaller city just northeast of Babylon) but his cult was far from the most popular. Unlike many other Babylonian deities, Nergal was mentioned in the Bible (2 Kings 17:30) and his name has therefore found a place among the demons and boogeymen of Christianity. If you search for “Nergal” on the internet you are likely to find the picture of a heavy metal singer from Poland dressed up in gothic makeup!
The Hannover Military Band
The Electorate of Brunswick-Lüneburg (colloquially known as the Electorate of Hanover) was a principality within the Holy Roman Empire. In the mid eighteenth century, the region was ruled by the Prince Elector, Georg II. A series of religious wars and a strange quirk of fate had made the house of Brunswick-Lüneburg the heirs to the British throne. Prince Elector Georg II was therefore better known to his English subjects and to history as King George II. In 1755, George II ordered his Hanoverian Guards Regiment to England. The Hanover Military band went with the Guards. One of the oboists of the band was named Friedrich Wilhelm Herschel. Friedrich was something of a musical prodigy: he also played the violin, the cello, the harpsichord and the organ. When the guards came to England, he liked the country and he left the band to move there permanently. He accepted the position as first violin and soloist for the Newcastle orchestra and later became the organist of the Octagon Chapel in Bath (a chapel attached to a very fashionable spa). Throughout his career Frederick William Herschel (for he had anglicized his name) composed a great many musical works including 24 symphonies, numerous concertos, and a large canon of church music.
Frederick’s music is forgotten today, but later in his life he found his true calling. As his musical career progressed, he became more and more deeply fascinated by lenses and mathematics. At the age of 35, he met the Reverend Dr. Nevil Maskelyne who was Astronomer Royal and Director of the Royal Observatory in Greenwich. Herschel began making mirror telescopes for Maskelyne, personally grinding the lenses and mirrors for up to 16 hours a day. He also looked at the universe through the telescopes he had made and reported his discoveries. What he found made him one of the preeminent scientists in history (he also became extremely wealthy and was granted a knighthood).
The Planet Uranus (or "Georgium sidus" as Herschel originally named it)
Herschel is most famous for discovering Uranus, the first planet to be found since the depths of antiquity. His other discoveries and ideas are perhaps even more remarkable. He was first to find out that the solar system is moving through space. He coined the word “asteroid” as a name for such objects. By observing Mars he determined its axial tilt and found that the Martian ice caps fluctuate in size. His attempts to determine if there was a link between solar activity and the terrestrial climate were unsuccessful (because of a lack of data), but formed the basis for successful work concerning both climatology and stellar physics. Astonishingly, Herschel discovered infrared radiation, the first non-visible electromagnetic radiation to be known. He accomplished this by passing sunlight through a prism and holding a thermometer just beyond the red end of the visible spectrum. He found two new moons of Saturn and two moons of Uranus. He correctly concluded that the Milky Way is a disk. He debunked the notion that double stars were optical doubles and showed that they are truly binary stars (thus demonstrating that Newton’s laws extend beyond the solar system).
Sir Frederick William Herschel, 1738 - 1822 (painted by Lemuel Francis Abbott in 1785)
In honor of his amazing career, numerous objects, devices, institutes and features around the solar system and beyond are named after Herschel (including the giant crater on Saturn’s moon Mimas). Few people have contributed so greatly to science or changed the conception of everything as much as this gifted Saxon oboist!
ferrebeekeeper 