APOD 2.8

14 January 2011
This picture shows the Quadrantid Meteor Shower, which emits over 100 meteors per hour from 2003 EH1, a radiant meteor near Polaris. The Quadrantids were named after the obsolete constellation Quadrans Muralis. Two of the meteors show up in the time exposure as crossing star trails, which I found interesting because the stars were visible for hours on end, yet the meteors lasted only seconds and still seem as bright as the star trails.

Sun Images

3D sun

Sun in infrared

Sun in radio

Sun in x-ray

William Rutter Dawes

Alex Kiefer

Mr. Percival

Astronomy

11 Jan 2011

William Dawes

        William Rutter Dawes was born March 19 1799 and died February 15 1868. He was British, born in London and raised in West Sussex. He was named after his father, who was a mathematics teacher. His father wanted him to be a clergyman in the Church of England, but Rutter Dawes opted instead to be a physician.

        Dawes’ interest in astronomy began when he met William Lassell upon moving to Liverpool in 1826. He wrote a letter to John Herschel explaining how he used a 1.6 inch refractor, Flamsteed’s Atlas and Rees’s Encyclopedia to draw diagrams of all known binary stars. In 1829, he took up astronomy as a profession after observing with Lassell. He also became a friend and apprentice of John Herschel. Dawes upgraded Herschel’s telescope to a 3.8 inch Dolland refractor which greatly improved the resolution for identifying binary stars. Dawes thus earned the nickname “eagle eye Dawes.” Dawes was elected a fellow of the Royal Astronomical Society in 1830.

        Dawes was influenced to return to religion by Rev. Thomas Waffles of the Independent Chapel on Great George Street in London. Dawes led his own congregation in Ormskirk. But when his wife died in 1839, he renounced his own congregation and joined that of George Bishop in London. Bishop’s observatory had a 7 inch refractor telescope, which Dawes used freely until 1844. He married a rich woman in 1842, and built his own personal observatory with a 6.5 inch Merz refractor. He discovered Saturn’s crepe ring along with W.C. Bond, but the latter worked at Harvard and his news didn’t cross the Atlantic before Dawes announced his discovery. Lassell attempted to observe the crepe ring with his 24 inch reflector, to no avail. However, when he visited Dawes and used the 7 inch refractor, making it out in a few minutes.

        After winning the RAS’s Gold Medal in 1855, he moved to Haddenham in 1857 and provided free medical service to its residents. His second wife died in 1860, and he observed until 1865, making drawings of Mars during its opposition in 1864. In 1867, Richard Proctor made a map of Mars based on them. He was elected a Fellow of the Royal Society, and died 4 years later.

        Dawes’s legacy consists of multiple craters on Mars and the moon and a gap in Saturn’s C ring which are named after him. Also, the Dawes limit, a formula used to calculate the resolving power of a telescope, is named after him because of its importance in observing binary stars, a focus of Dawes’s.

Works Cited

Oates, Michael. "William Rutter Dawes (1799 - 1868)." The Home of Amateur Astronomy in the UK. 30 Nov. 2009. Web. 11 Jan. 2011. <http://www.mikeoates.org/astro-history/dawes.htm>.

"William Rutter Dawes." Wikipedia, the Free Encyclopedia. 8 Sept. 2010. Web. 11 Jan. 2011. <http://en.wikipedia.org/wiki/William_Rutter_Dawes>.

APOD 2.5

12/01/2010 Martian Moon Phobos from Mars Express

Phobos is the larger of Mars's two moons. It is irregularly shaped, loaded with craters and resembles a potato. My theory is that a Russian astronaut from the ISS dropped his lunch during a spacewalk and it ended up orbiting Mars. It's unfortunate that the thick layer of dust covering Phobos precludes us from landing a probe on it, but if a human could ever reach Phobos, it would be a barrel of monkeys to wade through 3 feet of galactic dust on a giant potato. It took me a while to figure out why Phobos rises twice on certain parts of the planet. Near the equator, Phobos orbits so fast that it traverses the sky twice before a Martian day has elapsed. Closer to the poles, Phobos is not visible at all because it's beneath the horizon.

APOD 2.3

11/09/2010 NGC 4452: An Extremely Thin Galaxy

At first I thought this was a picture of a frisbee in space, but it turned out to be a view of galaxy NGC 4452 from the plane of the galaxy itself, which is even cooler! It is located in the Virgo Galaxy Cluster, which is the closest to the to the Milky Way. It is a lenticular galaxy, which is a disc galaxy that's used up most of its interstellar matter. It is roughly as thick as the Milky Way. The picture is almost perfectly edge-on with this galaxy. This would probably greatly surprise the average person who doesn't know much about astronomy, because they think it's all just stars and bright spots of light, whereas there are actually lots of interesting shapes like this line segment or molecular dust clouds.

APOD 2.2

10/30/2010 Ghost of the Cepheus Flame

This picture is very frightening. The molecular dust cloud kind of looks like a seahorse. The constellation Cepheus contains several star forming regions. The Cepheus Flare is a star forming region of low and intermediate mass. The main nebula is the Ghost Nebula, whose brown color is caused by the stars behind it. The double stars are the beginnings of a binary star. It's fitting that they used a picture of the ghost nebula on the day before Halloween.

APOD 2.4

The 11/14/2010 picture is an artist's representation of the concept of the multiverse. Obviously one cannot take a picture of an alternate universe, as with most astronomical phenomena, so the picture is really just a chance for the artist to doodle some circles and neat colors and call it a multiverse. Essentially, the multiverse is the collection of universes. Many scientists don't even agree that there are other universes, but they are hypothesized to explain where matter goes when it falls into a black hole, for example. It is very tantalizing to ponder what life is like for parallel analogues of myself in other universes. For instance, while I chose to eat a peanut-butter and jelly sandwich for lunch today, my parallel twin might have eaten a Caesar salad. Scientists are pondering other, less important issues pertaining to the multiverse, but there is virtually no way to empirically test them.