APOD 4.5

Picture from April 27, 2011

This is dark region of gas and dust is known as NGC 6231. In the constellation of Scorpius, it is sometimes called the "Dark Tower" because of its shape and ominous presence. The structure itself, which spans almost 40 light years and is some 5,000 light years away, was shaped by a barrage from ultraviolet radiation from the nearby OB association (a small, young group of hot, massive stars) of stars. This is the same radiation that causes the surrounding reddish glow through interactions with hydrogen gas. The large amount of stars in the background is due to the fact that Scorpius is in a direction close to that of the center of the galaxy, where the density of stars is much higher.

Astronomy Cast - Ep. 214: Space Tourism

This episode of Astronomy Cast focuses on the prospect of civilian space travel, or "space tourism," a topic of great interest for me. Space tourism is, of course, currently not a highly developed industry to say the least. The hosts talk about how 0-g flights are probably the closest thing to space travel that untrained space tourists can hope for today. These flights consist of a plane that flies in a parabolic path so that on the way up gravity feels intensified, but on the way back down passengers experience the sensation of weightlessness. Also, Space Adventures, the company that offers these 0-g flights, also has a program that allows prospective space travelers train alongside astronauts (for a large sum of money). This allows them to actually go into space in the International Space Station for upwards of 10 days. Looking towards the future, however, there are several projects in the private sector being worked on with the goal of allowing regular people to experience sub orbital flight (and eventually, orbital flight) for a reasonable price. The most prominent of these projects is the one headed by Richard Branson and and his Virgin Enterprises, which has already had successful test flights. I think what's interesting to imagine is what opportunities might be available in the future, especially with the talk of an outpost on the moon. I certainly hope that this industry will see much more development in my lifetime.

Zooniverse Update 2

Lately on Zooniverse I've been focusing more on Galaxy Zoo. I have noticed an unfortunate trend which is that a good many of the pictures are of what look like blurry, amorphous objects. This makes it difficult at times to properly classify the galaxies. However, some pictures, especially those on Galaxy Zoo 2, are quite clear and magnificent. These pictures are often of quite interesting galaxies as well. I have seen several well-defined spirals, as well as a picture of two galaxies that appeared to be interacting. I'm curious about some of the other "odd" things that can appear, such as how a ring or arc might look, and am hoping to come across one of those in the future.

APOD 4.4

Picture from April 24, 2011

This celestial eye staring through space is none other than the Cat's Eye nebula. The nebula is a prime example of a planetary nebula, which actually has nothing to do with planets. Planetary nebulae are instead the result of dying stars expelling their outer layers. The star shrugs off the layers in a series of regular convulsions, producing the of concentric "shells" seen in the picture. After all the expelled material has been dispersed into space, all that will remain is the white dwarf star in the center. This is also the predicted fate of our own sun when its life comes to an end some 5 billion years from now.

APOD 4.3

Picture from April 21, 2011

The bright stars in the foreground of this picture are inside our own Milky Way Galaxy. However, the two galaxies in the background that are the subject of the photo are over 300 million light-years distant. The galaxies, known as Arp 273, are very close together for galaxies (a little over 100,000 light years), and appear in this picture to be distorted. This is due to their gravitational interaction as they engage in close encounters. Despite the unusual appearance, galactic interactions and mergers are quite common in the universe. In fact, the Milky Way and its cosmic neighbor, the Andromeda Galaxy, are expected to have a similar interaction in the distant future.

Zooniverse Update 1

In the Zooniverse project, I have been mostly focusing on Planet Hunter. I have found that in many cases, I have found that locating the transit features is very subjective, and they are rarely very apparent. There was even one instance where the system inserted a simulated planet in the light curve that seemed virtually undetectable. There was, however, one star (which I marked as a favorite) where the curve seemed to show very clear transit features much more dramatic than any of the others. I have also done some work in Galaxy Zoo classifying galaxies. The majority of the galaxies appear to just be "smooth," but some are pretty interesting. A few that I saw were highly irregular, which I found interesting.

APOD 4.2

Picture from April 6, 2011

This galaxy happens to be the spiral galaxy M74 in the constellation of Pisces. It is a highly photogenic galaxy due to the face that we have a nearly perfect face-on view of it. It is classified as an Sc galaxy on the Hubble sequence due to its relatively loosely wound spiral arms, which are traced by bright blue star clusters and dark cosmic dust lanes. The red in the picture is from star-forming regions and is visible due to the exposures taken from hydrogen atom emissions. The picture itself spans about 1 degree of the sky (the radius of the full moon) and was taken with 19 hours of exposure using a 1.23-meter telescope.