APOD 4.1:Large Magellanic Cloud

The picture is an infrared portrait  of enormous cosmic dust clouds strewn across the Milky Way's satellite galaxy, the Large Magellanic Cloud. There is something about it, perhaps the way the lighting looks, that render it both heavenly and hellish in appearance. It's a composite image fom the Herschel Space Observatory and Spitzer Space Telescope. The Large Megellanic Cloud, 30,000 light-years across and 160,000 light-years away from Earth, is a neighboring dwarf galaxy, filled with dust clouds in which temperatures denote the occurrence of star formation. Where there are blue hues, there is warm dust heated by younger stars. The red and green show dust emission from cooler and intermediate regions of beginning star formation. The brightest region is actually the Tarantula Nebula.

Astronomy Observation Log 3.3 (Astronomy Cast - Exploration of Venus)

Apparently, the planet Venus has also been the subject of a number of in-depth explorations, even if these efforts haven't been as publicized as those of Mars.

The science fiction interpretation of the past was interesting and almost funny- the speakers recount a story, perhaps by Asimov, that was adapted into a movie in which people lived on the warm wet world that was Venus, which would only be clear of rain every 20 years. One child was stuck inside during the "fun" of a clear day, which seemed sad at first, except the kids that went out to play all died horrible deaths burning in sulfuric acid. He ended up being lucky for being unlucky.

Scientists had no clue what was going on with Venus. From Earth we could see it had an atmosphere and that it had phases. By 1960 when we started bouncing radio waves off the surface we could see it was a rocky planet. It was not until 1962 we knew it was a "hell-scape" with insanely high temperatures, totally unfit to be considered a planet capable of harboring life. In the 60s there were many failed missions to Venus.

"Venera 4" in 1967 finally measured the atmosphere of Venus- not only was it hot there, it was 95% carbon dioxide, totally different from what astronomers expected. The atmosphere is so thick (it's 22 miles thick) it could almost crush spacecrafts. Many engineering challenges were faced.  Probes, devices and communication methods indeed need to be able to penetrate through 22 miles of sulphuric hail.

In the late 1970s, through the "Pioneer" program we sent four different probes through Venus' atmosphere to take data as they traveled- not only did the atmosphere have extremely high pressure, but we learned the winds are incredibly turbulent. Yet a certain altitude in the cloud layer, you can get a pressure and temperature that are the same as those found on Earth (even though you couldn't breathe the air, you could sit outside in this area if you were on some floating station).

Venus is fascinating to observe, with evidence of past oceans, vortexes in the polar region of the atmosphere near the South Pole, and the presence of hydroxyls. The main problem is protecting the instruments against the intense heat...  After that, the pressure bearing down on all sides is the problem. At least the Russians have got some steel-reinforced drawing boards! The Russians have historically seemed to have the upper hand in Venus exploration.

APOD 3.8: Sakurajima

It looks very alien for a volcanic eruption to produce lighting, as Sakurajima does in this picture. Located in southern Japan, Sakurajima volcano was erupting in early January, the magma being so hot it glowed. Liquid rock burst forth from beneath the surface. Volcanic lightning is currently a prevalent research topic because it is still a somewhat mysterious phenomenon; the lightning bolts help "quench areas of opposite but separated electric charges." One hypothesis posits that magma bubbles and volcanic ash are electrically charged, and created separated areas with their motion. Or, charge-inducing collisions of volcanic dust could spur on a spot of lightning, which strikes 40 times each second, somewhere on Earth.

APOD 3.7: Tardigrade!

The picture, credited to Nicole Ottawa and Oliver Meckes, is one of the weirdest coolest things I've ever seen- especially since it's actually a real picture from nature from an electron micrograph. The milimeter-long creature is an adorable moss piglet- aka the tardigrade. Officially, this polyextremophile is a new favorite animal of mine, and it's also a subject of close study. Since it can survive such incredible pressures, it was the first animal to be sent into space, and it survived hard vacuum. It was tested in 2011, actually outside the space shuttle. Tardigrades are extremely hardy, being able to go for decades without food and water, survive far above the boiling point or near absolute zero, and survive under direct exposure to dangerous radiation. This is partly because they can repair their DNA and reduce body water content to a few percent. Tardigrades were also launched to the Martian moon Phobos on Russian mission Fobos-Grunt, but the rocket failed and they only stayed in Earth orbit.

Dorothea Klumpke Roberts

Letts 1

Olivia Letts

Mr. Percival

Astronomy, Per. 3

7 Mar. 2013

Dorothea Klumpke Roberts: Life and Contributions

            Dorothea Klumpke Roberts was born in San Francisco in 1861, where her German immigrant father John Klumpke arrived and attempted to strike it rich in gold.  While his gold prospecting efforts were a flop, he became a wealthy real estate broker instead, and fathered five daughters and two sons with his new wife.  One son died in infancy and the other became a businessman, though Dorothea, the third born, and her four sisters all became renown for their artistic, musical, and scientific pursuits.  The girls were all educated in elite schools in Germany, Switzerland, and France; Dorothea ended up enrolling at the University of Paris (the Sorbonne), where she switched from studying music to studying her true passion, astronomy.  After attaining a Bachelor of Science degree in 1886, she received a post at the eminent Paris Observatory.  Here, she worked on a 34 cm refractor with which to photograph the minor planets, or asteroids.  Her skill set was mathematical in nature, and she also measured star positions, and studied meteorites and stellar spectra.  That same year, Scottish astronomer Sir David Gill and Director of the Paris Observatory Admiral Amédée Mouchez initiated a “Carte du Ciel” project to create an atlas of the entire sky, including all stars even down to the 14^th magnitude and a list of those down to the 11^th magnitude.  As the Paris Observatory was to handle a major portion of the sky, there was fierce competition for Director of the Bureau of Measurements, who would head the bureau in handling plate measurements and reductions.  Dorothea Klumpke won this position and held it until 1901; the project was a success.  Her doctoral thesis, “L’étude des Anneaux de Saturne,” a mathematical insight into Saturn’s rings, was highly acclaimed and well-defended,

Letts 2

thus Klumpke became the first woman ever to attain the Docteur-és-Sciences degree.  In 1896 she traveled to Norway for a solar eclipse that ended up being obscured by clouds, yet she met her future husband Dr. Isaac Roberts, a pioneer astronomer who produced the first good pictures of the Andromeda Galaxy.  In 1899, the Meudon Observatory chose Dorothea Klumpke to ride in a hot air balloon called La Centaure above Paris to observe a Leonid Meteor Storm.  The numerous Leonids are from the comet Temple-Tuttle and seem to come from the constellation Leo, after which they were named.  In 1799, 1833, and 1866 the Leonids filled the skies with magnificent shooting stars, but only 15 of them were observed during Klumpke’s seven-hour balloon flight.  Still, her ride only made her more popular and was a milestone for women in the male-dominated field of astronomy.  In 1901, when Dorothea married Dr. Roberts, she left the Paris Observatory for her husband’s observatory and home in Sussex, which he called “Starfield.”  She assisted him in his project to take pictures of all 52 Herschel Areas of Nebulosity, although he died three years later, and all his money and astronomical equipment went to her.  She completed the remainder of the work and brought all the photographic plates with her back to Paris, where she went back to work for the Paris Observatory and spent years measuring, reducing, and printing she and Isaac’s work.  It was not until 1929 that she published "The Isaac Roberts Atlas of 52 Regions, a Guide to William Herschel's Fields of Nebulosity,” to which she added a supplement in 1932.  Dorothea Klumpke Roberts published two photographic atlases and deep sky object catalogues for which she attained the Hèléne-Paul Helbronner prize from the French Academy of Sciences.  In 1934, for 50 years of astronomical study, the president of France awarded her highest honor as she was elected a Chevalier of the Legion d'Honneur.  She spent the rest of her days in San Francisco with her sister Anna, who was a famous painter and protégé/companion/heir to Rosa Bonheur.  Two minor planets were named in honor of Dorothea Klumpke Roberts, along with the Astronomical Society of the Pacific’s Klumpke-Roberts Award.

APOD 3.6: Mercury

The MESSENGER orbits Mercury, using radio science investigation and seven instruments to attain more knowledge about the evolution and history of the planet.  The picture is from image data collected from this spacecraft with a wide angle camera, and the colors would not normally be seen but they reveal the richly complex regions of Mercury. Apart from chemical and mineralogical areas that cause the variety of appearances there are many physical features such as the Caloris basin, seen in the upper right of this angle of the planet. It was created by an ancient comet or asteroid, then the area was flooded with lava. The light blue areas were also created by impacts, although ones that occurred more recently. The beautiful blue areas are low reflectance terrains.