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!

Stars in Spiral Galaxies

Spiral Galaxy M74

When most of us think of a galaxy we think of a beautiful spiral shaped entity. Astronomers have been studying these spiral galaxies for quite some time now, and have noticed that most of the stars seem be located within the arms. To form a star, you need a giant cloud of molecular hydrogen, and other gaseous materials. The cloud will eventually collapse due to gravity and form stars, and some of those stars may even host planetary systems. Most of the material in a galaxy (gas, dust, rocks, etc.) sits in the spiral arms in the plane of the galaxy. So it makes sense that stars tend to form here; it’s where all the stuff is!  Because the spiral arms contain millions of stars, they glow very brightly in optical light. This allows Hubble, and other telescopes, to image the structure of the galaxy. M74, pictured above, is a perfect example of a spiral galaxy whose structure is illuminated by the light from many stars within its spiral arms.

Image Credit: NASA, ESA, Hubble Heritage(STScI/AURA)-ESA/Hubble Collaboration 

Curiosity Self Portraits

I'm sure many of you heard about the Mars Science Laboratory: Curiosity in the news back in August. The rover successfully survived the trip and descent to Mars, landing safely in the early morning hours on August 6th (EST). Much of the scientific community was fretting about Curiosity surviving the landing due to all of the creative engineering maneuvers that needed to go of without a hitch for the rover to survive. Thankfully everything went smoothly and we are now beginning to study the Martian surface! A young girl, who has seen many of the photos the rover has taken, asked me why it keeps taking self portraits. "Why not point the camera at the Martian surface?" she asked. "We already know what the rover looks like. It's almost like he's taking a picture of himself for Facebook!"  There is good reason for Curiosity to take pictures of itself, and that is to make sure that everything is functioning properly. We want to make sure that nothing broke during Curiosity's trip, and we also need to make sure that camera, levers, wheels, etc. are all working as they should. Once we trust that everything is working properly, we can start to move the rover and do experiments. So we expect to see many more close ups of Curiosity on Mars, just as a sort of "check-up". Below is an image of almost the entire rover sitting on the Martian surface. Everything looks good to me!

Image credit: NASA/JPL-Caltech

Is Today Affecting Yesterday?

I came across an article this morning, that’s more about quantum physics than astronomy, but it was so fascinating that I just had to share it with you all. Physicists may have discovered a way that the future can alter the past! Yup, you read that right, what you do today could affect what you did yesterday! How can this happen? Quantum physicists are studying the ideas of non-locality and causality. Non-locality is the idea that two particles can be entangled such that an action on one automatically affects the actions of another. Kind of like two train carts tied together, if I move one the other moves as well. Causality is the idea that tiny particles exist with unknown properties until someone makes a measurement of one of those properties, and these measurements can be strong (I know for sure this is true about the particle) or weak (I think this might be true).

For example, lets say you glance super quickly at an unknown street sign, then look away. You might notice that the sign had a reddish color to it (weak measurement). You look quickly again, and notice there is also some white (weak measurement). Repeat the process and eventually you might figure out that you are looking at a stop sign. Then you stare directly at it for a few seconds (strong measurement) and for sure decide that it is a stop sign. The idea of causality states that the street sign’s properties are unknown (what type of sign is it?) and the signs location is unknown (where is it?) until you look at it and decide it’s a certain one in a certain spot. So how can observing an object properties today affect it yesterday? Try this thought experiment below

A friend and I live in Upstate New York, and we live 50 miles apart. You don’t know where exactly we live, but only that our houses are 50 miles apart and that our bodies are always 50 miles apart no matter what (we are entangles that way). Now you decide you want to figure out where I currently am. You can’t do this by calling or asking me, you have to put tiny bits of information together to figure out where I am (weak measurements). Ok, so you know that I just posted this blog, and therefore, I must be somewhere where there is wifi. You just made one tiny measurement of where I am, without defining exactly where I am. There are tons of place with wifi, so I could be at any one of those places. Measurement number 2, again I’m writing this blog post , so I must be at a computer (for the sake of argument, lets assume it must be a desktop computer). So now, with two measurements, you’ve narrowed down where I am (somewhere with wifi and a desktop computer), but still don’t know exactly where I am. Let’s pretend you were able to make a whole bunch of other measurements and finally figure out that I am at the local library, 10 miles from my house. Now that you’ve made a solid measurement of where I am, you have fixed me in place, and thus fixed my friend in a place exactly 50 miles away from me. Since I am 10 miles from my house, my friend must also be 10 miles from her house (because we are always 50 miles apart). But how did she get there? Sometime in the past, she must have drove from her house, to a point 10 miles away from her house. But we didn’t know or decide that she was 10 miles from home until we figured out where I was located, just now. The act of deciding that I am 10 miles from my house right now, put my friend 10 miles from her house, and thus altered the past in such a way that caused her to drive 10 miles away from her house sometime in the past. So my action of being at the library today, had an affect on what my friend did in the past, or in other words, the future (today or tomorrows actions) had an affect on what happened yesterday!

So what does this all mean? Are your actions today changing the past? Well, physicists aren’t really sure. They think they see this occurring for special particles that are entangled together and have certain kinds of properties. It doesn’t necessarily work on a human scale. But if we understand what’s going on in the quantum world, we may someday be able to use it in the “real” world…

Here is a link to a nice article explaining this in more detail: http://physicsworld.com/cws/article/news/2012/aug/03/can-the-future-affect-the-past