Monthly Archives: December 2010
It turns out, a lot.
NASA and the National Science Foundation have used balloons to learn about natural phenomena during part of each Antarctic summer from December to February. The balloons are launched to collect data that will help us understand phenomena in the universe-from the extreme to the every day-and this year’s balloon launches occurred on Monday.
Before you balk Sarah Palin-style, consider that balloons can go where we can’t-floating outside of our atmosphere, collecting data for us, exposed to the elements with relatively little consequence. It may not sound very sophisticated, but relatively speaking, having a balloon float around to collect data is way cheaper than having a more sophisticated vehicle for data collection like, say, a shuttle. And when you hear about how these are made, you might rethink balloons as unsophisticated party decor to boot.
Among the experiments being done with these balloons, the Cosmic Ray Energetics And Mass (CREAM) experiment was designed and built at the University of Maryland. CREAM is investigating high-energy cosmic-ray particles that originated from distant supernovae explosions in the Milky Way and reached Earth. Currently, CREAM VI is floating 126,000 ft above Antarctica with active science operations. The CREAM balloon is pictured above.
Another experimental balloon, the Balloon Array for Radiation-belt Relativistic Electron Losses (BARREL) experiment was designed and constructed at Dartmouth College. BARREL will help us understand the scientific basis of the Northern Lights by providing answers on how and where Earth’s Van Allen radiation belts, which produce the polar aurora, periodically interact with Earth’s upper atmosphere.
Next in line will be an experiment from the University of Pennsylvania called the Balloon Borne Aperture Submillimeter Telescope (BLAST). This experiment will investigate how magnetic fields impede star formation in our galaxy, helping us understand how forces interact in the universe to give rise to stars. BLAST’s instrumentation and telescope will collect data to make the first high-resolution images of magnetically polarized dust in a number of nearby star forming regions. There will also be some really dope pictures coming out of this experiment.
The balloons used these experiments are pretty sophisticated, made of a lightweight polyethylene film, flying to altitudes of nearly 25 miles, the balloons carry payloads weighing up to 6,000 pounds. That’s like strapping a mid-size SUV to a massive balloon made of Saran wrap. A nearly circular pattern of gentle east-to-west winds that lasts for a few weeks allows the recovery of a balloon from roughly the same geographic location from which it was launched, and permits a flight path that is almost entirely above land-the balloon can go extremely high and whips around in circles that cover lots of ground, landing relatively close to the site of the launch. You can see the circular path of one balloon below.
The beauty part is that you-yes, you-can track the balloons in real time, along with the scientists. Google maps illustrate the real-time path of the balloons as they float above Earth on their missions, and you can take in video footage of balloon collection as they descend.
The whole thing gives you a nice window into the day-to-day work that scientists are doing in extreme locales to understand the universe without actually having to leave your sofa. So make it a scientific holiday-while the kids follow Santa from the North Pole, you can keep track of scientists hard at work at the other end of the world.
A rare duo of astronomical events, the December 2010 lunar eclipse occurred on the December 21 winter solstice to produce a beautiful light show for those who were lucky (and awake) enough to watch. During a lunar eclipse, the Earth intercepts the Sun’s path to the Moon, casting a shadow on the Moon that appears red, amber, or gray. Lunar eclipses occur at least twice a year, so you will certainly be able to see the event again. The special part about this particular eclipse, however, is its timing: The last time an eclipse occurred on the solstice was on 1638 (372 years ago), and the next one is projected to occur in 2094. On the day of the winter solstice, the tilt of the Earth is at its farthest position from the Sun, giving us winter. This also makes the day of the solstice the shortest of the year.
The eclipse began on December 21, 2010 at 12:33 AM, and the Moon was completely engulfed in the Earth’s shadow at 1:41 AM (CST). Take a look at this time lapse video for a peek if you missed it:
So when is the Earth’s shadow visible? Well, it’s actually the moment in the video when the Moon turns red. Sunlight is made up of all colors of the spectrum, from red to violet, and then some beyond the visible spectrum. The Earth’s atmosphere scatters blue light (which is why the sky is blue), so the light that makes it to the Moon is red, causing a red shadow to appear on the Moon’s surface.
Why do you see the Moon go black before it becomes red? Shouldn’t it just go from white to red? If you look at a picture of the Sun, Earth and Moon during a lunar eclipse, you can see that sunlight from each edge of the sun crosses each edge of the Earth, creating cone-shaped shadows in space called Penumbra. These shadows appear on the Moon’s surface as darkness before the Moon moves directly into the Earth’s path, or Umbra.
You can also view this from the Moon’s point of view!
Speaking of the Moon’s point of view, the temperature of the Moon goes wild during lunar eclipses. Ordinarily, the temperature of the surface of the Moon exposed to the Sun (during a full moon) is 266 degrees Fahrenheit. During a lunar eclipse, the temperature of the Moon drops to -146 degrees Fahrenheit-all in the span of 90 minutes! The lack of an atmosphere on the Moon means that it can’t control heat loss into space during an eclipse. Kind of makes you want to do something nice for the ozone layer, right?
Some really gorgeous photos were captured from this event. This one, from a viewer in Manhattan, caught this shot of the Moon from her balcony:
The nice thing about lunar eclipses is that, unlike solar eclipses, in which the Moon blocks the Sun’s path to the Earth, lunar eclipses can be viewed from anywhere in the world at night, and don’t require special eye protection, although visibility is optimal in different parts of the world during different eclipses. There will be two lunar eclipses in 2011: June 15, 2011 and December 10, 2011. Get out there!