Orion Proplyds

The Orion Proplyds were first discovered by the Hubble Space Telescope. Astronomers expected the Orion nebula to be a host for lots of star formation, and were amazed to see that Hubble could resolve individual young stars. The Proplyds are young stars surrounded by a gaseous circumstellar disk . In the image of the Orion Nebula above, the proplyds are enlarged so you can see the bright central star surrounded by a dark oval shaped ring. The disks appear dark because they are absorbing the light emitted by the nebula, and re-emitting it in the infrared, a wavelength of light that does not appear bright in these images. Portions of these disks will eventually fall onto the star, and the rest will either form planets, or be dispersed back into the nebula. Astronomers are using these, and other images of young stars, to learn about how stars form and how planetary systems evolve.

Image Credit:

NASA, ESA, M. Robberto (Space Telescope Science Institute/ESA), the Hubble Space Telescope Orion Treasury Project Team and L. Ricci (ESO)

American Flags Fading on the Moon

Image of an American flag from the moon's surface during the Apollo missions

During each Apollo mission that made it to the moon, the astronauts  left behind an American flag. Each was attached to a poll, and designed to wave horizontally in the low gravity environment. Astronomers have been studying these flags over the years using moon orbiting satellites to take photos of them. Even though they are not able to resolve the flag in the images, they can see a color difference in the photo where the flags sit. In more recent photos, astronomers have noticed that the flags appear a little brighter than they expected. Why is this? They think that the flags are fading, big time! If you've ever flown a flag outside and left it out all summer long, then you might have noticed that the colors look a little less bright over time. Now imagine this same flag on the moon, where there is little to no atmosphere to protect the flags from being bombarded by harmful UV radiation. It's likely that the sun has not only faded these flags but sun-bleached them white! Regardless of what they look like today, they are still a symbols of the fantastic accomplishment of landing man on the moon. 

Image Credit: NASA/Apollo Mission

Shiny Martian Rocks

The Curiosity rover has been exploring Mars since early August, and has taken many beautiful photos of the Martian landscape. In early October, Curiosity took its first scoop of Martian soil to be placed inside SAM, an instrument which analyzes the composition of Martian soil. With the scoop of soil in hand, curiosity photographed the area where the sample was taken, and stumbled upon a strange looking shiny object (center of above image).  At first, astronomers who analyzed the photograph thought the object was a small piece of shrapnel from when the rover landed.  This brought testing to a halt, because astronomers did not want to run a piece of sharp shrapnel through a very delicate machine meant to filter and analyze soil. About a week prior, Curiosity photographed a piece of plastic with ChemCam that likely broke off during it's descent, so it was very possible that this was another piece. Just to be safe, Curiosity dumped the soil. Upon closer inspection of this shiny rock, astronomers realized that this was not a piece of metal or plastic, but rather a strange rock of Martian origin. What these rocks are made of is still unclear, but Curiosity can now safely use SAM to analyze soil samples and hopefully find out the composition of these rocks!

Image credit:

 NASA/JPL-Caltech/MSSS

Iapetus, the Dinosaur Moon

Iapetus is a moon of Saturn with a funny name and a funny geological feature. I always think of it as the "dinosaur moon", because it has a distinct ridge feature on its surface that reminds me of the back of a dinosaur. Orbiting at 2.2 million miles from Saturn's surface, it's farther away from Saturn than Titan is. The surface of Iapetus was imaged by the Cassini mission in 2004, and the images revealed the equatorial ridge, a 6 mile high mountain range. It's a bit unclear how this band of mountains ended up on Iapetus. One theory is that a long time ago, Iapetus had a ring similar to Saturn's ring. As the moon evolved, the ring began to collapse onto the surface, and this ridge is where all the material collected. A second idea is that the ridge formed during a time when Iapetus was spinning on its axis much faster than it does today. Bodies in space, such as the Sun and the Earth, spin on their axis. Because of this, they bulge just a little bit in the middle. So Earth and the Sun are not perfect spheres, but rather balls that are slightly wider at the center. If Iapetus was spinning really fast some time in the past, this ridge might be the result of the moon bulging in in the middle. Astronomers will have to take a closer look at the composition and orbital properties of this moon before they can determine exactly how the ridge formed.

Image Credit: NASA/JPL/Cassini

Astro Plans for 2013

It's that time of year when everyone is making new year resolutions, and I am no different. My goal this year for you, my readers, is to write a blog post at least once a week. So today, I thought I'd share with you some exciting events of 2013; a hint at blog posts to come.

This year is going to be just as exciting as years past for astronomy enthusiasts. NASA has many missions planned, including the launch of the Interface Region Imaging Spectrograph (IRIS), Lunar Atmosphere and Dust Environment Explorer (LADEE), and the Mars Atmosphere and Volatile Evolution mission (MAVEN). These instruments are designed to study the solar atmosphere, moon's surface, and Mars' upper atmosphere, respectively. Along with these new satellites, NASA and other agencies will continue  to support the International Space Station and science experiments being conducted there.  The ESA will also be very active in 2013, focusing on launching satellites to study the Earth as part of their Living Planet Programme. Work will continue on the James Webb Space Telescope (JWST), and the construction of the Atacama Large Millimeter/submillimeter Array (ALMA) should be completed. Data continues to pour in from the Great Observatories Hubble, Chandra, and Spitzer, along with various missions exploring our solar system. Astronomers are actively studying this information and continue to make discoveries pertaining to star, planet and galaxy evolution. The Kepler space telescope, along with ground based observatories, continue to discover new exoplanets on a weekly basis. Maybe an Earth analog will be uncovered in 2013? Towards the end of 2013, be on the lookout for comet ISON. It's expected to whiz by Earth in December, and will appear as a small dot as bright as the full moon traveling across the sky.

For more information on these events, and, of course, some basic astronomy topics explained, check back on a weekly basis!

Image Credit: NASA/JPL-Caltech, space.com

Can I See the Stars?

Clear skies are essential for astronomers, but depending on where you live they may be few and far between. If you want to do some star gazing, but aren't sure if the weather will cooperate, take a look at the clear sky clock (http://cleardarksky.com/csk/). All you need to do is click "find a chart" and enter your location (or chose a state then city). What you'll see is a chart telling you all sorts of weather predictions, but the most important one is the cloud cover. Above is a clear sky chart for Kitt Peak, AZ, and you want to look at the top row of boxes to see if the sky will be clear. The color of the box at a given time tells you if there will be clouds in the sky (white), or if the sky will be clear (dark blue). So it looks like the sky will be cloudy before midnight Saturday, and then crystal clear the next day and a half. Below the chart there will be a description of how to read the chart and what the colors correspond to exactly. The chart is usually very accurate and astronomers use it all the time while observing. So the next time you want to go to a local star party, but aren’t sure if you should bother going because it might be cloudy, take a look at the clear sky chart before you head out.

Department Store Telescopes

Have you been looking up at the stars recently and thought about purchasing your own backyard telescope? Have your kids put telescope on their holiday wish list? Do you want to learn how to take photos of astronomical objects? If you answered yes to any of the above questions, then I have one piece of advice for you: don't buy a department store telescope! Yes they are inexpensive and promise to show you beautiful images of the moon and planets, but they are more hassle than they are worth. I've had many friends and family members purchase these telescopes, struggle with their kids for hours in the back yard trying to see something with it, only to package it up the next day and toss it or re-sell it. Why are these telescopes so "bad"? Well, bad is really a poor choice of words. They are usually refracting telescopes designed to look at large bright objects, and they do a good job of that. One of the main complaints I get from people is that the images look blurry, so they try to magnify the image by inserting a higher magnification eyepiece, in hopes of getting a clearer view. What they don't realize is that magnification only blurs the image more. Theses telescope are small (usually a few inches wide) and only collect so much light. Magnifying that light is not going to make things more clear or brighter, its going to enlarge a small dim region, and likely make it look darker than before. The image you see will never look like the one on the box, guaranteed. The second complaint I hear is that they are difficult to "point", as in, even if you think you have it aimed at the moon, you can't see anything. This is a problem with all small, non-computerized telescopes, and can get really frustrating really quickly. My best advice here is to be patient and try to learn your way around the sky. Point the telescope towards the moon and practice lining it up by looking at the stars with your eyes, then through the telescope, and adjusting as necessary. Practice makes perfect with this. Lastly, you must remember that we live on a moving rotating sphere, and therefore, when you point your telescope at an object, it will only stay in your field of view for a short time before you have to readjust. This is true for all telescopes, unless you have one that "tracks".

So, I very much encourage you to buy a backyard telescope, and I don't want a bad experience with a cheap scope to detour your love of astronomy! You can still acquire an excellent, easy to use telescope for a few hundred dollars. Check out websites like http://www.celestron.com/ and http://www.meade.com/ and do your research! Ask friends in a local astronomy club what they suggest, or attend a telescope buying seminar. Often, local museums will offer workshops on how to purchase and operate basic telescopes for the beginner. Check these out, avoid the department store telescopes, and I promise you will love your new investment. Clear Skies!