Archive for November, 2008

Double Checking Our Data

Wednesday, November 26th, 2008 by Bellatrix

Scientists believe they have found the answer to a mystery about a thought to be nearby galaxy. The funny thing is this answer was found by rather serendipitously after finding out our current estimates for the distance of the galaxy were wrong.

The galaxy named NGC 1569 was a bit of a mystery. It is an irregular shaped dwarf galaxy, which isn’t in itself strange, but the galaxy was going through a burst of star formation with no discernable reason. The galaxy was forming stars much faster than any other galaxies in its nearby region. Well then we realized that the problem with that statement was not NGC 1569 itself but the galaxies we thought were nearby it.

Scientists recently pointed the Hubble Space telescope at NGC 1569 to scan for red giant stars. The astronomers were hoping to get an estimate of the galaxies age by looking for red giants, as red giants can be used as reliable standard candles for measuring distance since they all burn at the same known brightness. However, the astronomers were only able to see the brightest red giants, even using Hubble, the stars were too dim to be resolved. This fact lead astronomers to question the previous estimate for how far away the galaxy actually is. And now after looking at the data astronomers have realized the galaxy is actually about one and a half times farther away than previously thought, making it about 11 million light years away.

The problem was before this the galaxy had only been studied with ground based telescopes, which have much less resolving power than space based telescopes, which can make estimates less accurate. With this new information the galaxy’s star formation makes more sense. This distance puts the galaxy in the middle of a cluster of ten other galaxies. The gravitational interaction of the galaxies tugging on each other would be enough to explain the high rate of star formation we see in this galaxy.

So using Hubble we have answered yet another question, good ol’Hubble. However, this instance makes one wonder how many other numbers that we have for things like distance or mass etc might be inaccurate after only being studied by ground-based telescopes. How many things should we go back over with space-based telescopes to make sure? And how many mysteries or unexplainable phenomena might be answered by simply rechecking our data??

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Large Deposits of Water-Ice Found on Mars

Monday, November 24th, 2008 by Evan Finnes

On November 20th, 2008, NASA confirmed that the Mars Reconnaissance Orbiter has discovered ancient glaciers of water-ice preserved under a layer or dust and rock. These subsurface glaciers are located at altitudes much lower than any previously discovered layers of ice, and also contain more water-ice than any other region on Mars, including the poles.

These glaciers were discovered underneath a formation that had been puzzling geologists for years. These formations are known as “aprons” because of the way they gently slope upwards. The glaciers were discovered after ground penetrating radars were pointed at these “aprons” because the radio waves were reflected without a significant loss of energy shortly after penetrating the surface. The radio waves that are not reflected travel through these formations with an apparent velocity, which is consistent with the composition of water-ice.

Hundreds of these apron-like features are located in latitude bands between 35 and 60 degrees on either side of the Martian equator. They are also commonly located beneath cliffs and are typically tens of kilometers long, and may be the remnants of a giant ice sheet, which may have at one time engulfed these mid-altitude regions. Many scientists believe that Mars was once tilted in such a fashion that the poles pointed toward the Sun, leaving the mid-latitude regions in a much cooler climate. This discovery offers proof to this hypothesis.

Studying these ice-sheets could help us understand processes that effect climate change, which is a poorly understood phenomenon, here on Earth. Our last glacial Maximum occurred about 20,000 years ago, when much of the North American and Eurasian continents were covered in an ice sheet over 3 kilometers thick. There are many factors which are thought to cause the onset of an ice age, such as: changes in the atmosphere, tectonic geography, variation in the Earth’s orbit, and variations in solar energy. The changes in the atmosphere which effect the onset of glaciers is not well understood, although, there is some proof that CO2 levels shrink during the onset of an ice age, and increase during interglacial periods. The effects of increased CO2 on the climate have long been a subject of great debate. Tectonic geography affects the onset of ice ages by arranging the continents in such a way that they prevent the flow of warm water from the equator to the poles; this allows the formation of ice sheets. These ice-sheets increase the planets albedo, which decreases the amount of solar radiation, which is absorbed. This decrease in absorbed energy allows the ice sheets to expand. There are three known configurations which block or reduce this flow of warm water–two of which exist today. A continent sits on top of a pole, such as Antarctica. Or a polar sea, such as the Arctic Ocean, is nearly land-locked. The third configuration consists of a single mass continent which covers much of the equator. Such a mass continent existed between 850 and 635 million years ago during the Cryogenian period, and was called Rodinia. Variations in the Earth’s orbit, called Milankovitch cycles, suggests that major ice ages occur every 100,000 years due to periodic changes in Earth’s eccentricity, axial tilt, and orbital periods; however, how these variations effect the climate are not well understood.

The discovery of these large volumes of water-ice on Mars will be very important to the future colonization, and manned missions to mars. This ice will serve as drinking water, and as a source of energy, which will be used in hydrogen fueled vehicles. This will defiantly reduce costs for such future missions because fewer supplies will have to be shipped to the red planet.

On Earth, such buried glaciers in Antarctica preserve traces of ancient organisms. So these Martian glaciers might also serve as a place to look for fossil evidence of past life on Mars. In addition to fossil life, localized heating due to volcanism may have melted some ice, which could provide an environment for microorganisms to evolve.

The discovery of subsurface glaciers on Mars will help us understand the processes which evoke climate change on Earth, provide a place to gather food and fuel for future missions to Mars, and could be one of the best places to look for signs of ancient organisms. Indeed, these will be places which will be thoroughly explored by rovers, Landers, and eventually, by mankind.

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“Out of the Box” Interviews Terence Witt

Wednesday, November 19th, 2008 by Aridian PR


“Out of the Box” Interviews Terence Witt: Author of Our Undiscovered Universe.

“Out the Box”, by Abrah-Cove Publishing, features hot topics/controversies that come right off the pages of self-published books. “Out the Box” is hosted by Martha Kimbrough and Dionne Hill.

The program with Terence Witt aired Wednesday, November 19, 2008 at 12:30 p.m. central standard time on

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Wednesday, November 19th, 2008 by Evan Finnes

Earlier this year, India celebrated the launch of its first mission to the moon. The mission is called Chandrayaan-1, which in Hindi, translates to “trip to the moon”. The mission was launched on October 22, 2008 using India’s own launch craft which is called the Polar Satellite Launch Vehicle. On November 8th, Chandrayaan-1 entered a lunar orbit at altitude of 100 km above the lunar surface.

Chandrayaan-1 is a multinational program with contributions from India, NASA, the Bulgarian Academy of Science (BSA), and the European Space Agency (ESA). The objective of this mission is to map out the lunar surface in greater detail than has ever been done before, by any single nation. This mission will Map out, in high resolution, the chemical and mineralogical compositions of the Moon’s North and South poles. It will also search for pockets of surface and subsurface helium, and water-ice which could be potentially used by a future Moon-base. The satellite will also map out changes in elevation, and the chemical composition of the moons interior by observing internal rock which has been exposed to the surface. It is hoped that the data gathered will help develop a better understanding to the evolution of the solar system, particularly, the origin of the Moon.

With the great success of Chandrayaan-1, the Indian Space Research Organization (ISRO) has announced plans for the launch of Chandrayaan-2 in 2011. For this relatively short mission (with a duration of approximately one month), the Russian Federal Space Agency (Roskosmos) will join the ISRO in the building of a lunar Lander/Rover. This mission will be very similar to NASA’S Martian Sample Return Mission, due to the fact that a solar powered rover would navigate across the lunar surface, collect samples and return them to an orbiting spacecraft, which will bring them back to Earth. The ISRO also has plans to launch Chandrayaan-3, 4, and 5, but the details of these missions have not yet been announced. Could India be planning a manned mission to the moon?

The reason we are still so interested in the moon is because of the fact that we still do not fully understand the processes which may have formed the moon. The leading hypothesis, developed by geologist Reginald Aldworth Daly, suggests that during the formation of our solar system, a hypothetical mars sized body called Theia smashed into proto-Earth. This collision would have caused Theia’s entire mantle, and most of Earths to explode into space, while Theia’s iron core sank into the Earth where it combined with Earths Iron core. The mantle debris, in orbit around the Earth, then would have accreted to form the current moon. This hypothesis also explains the unusually large size of Earth’s core. There is some evidence which supports this hypothesis: the lunar rocks gathered during the Apollo mission were found to contain oxygen isotopes with compositions very similar to Earth. Also, large areas of the lunar surface appear to be igneous, which means that it was once molten, and the energy produced during a large collision would be high enough to produce large scale melting of lunar rocks.

It is always exciting when other nations become more involved with space exploration, and contribute more to the collective knowledge of our surrounds. It will be interesting to see if Chandrayaan-1 will be able to produce data that will confirm the Giant Impact Hypothesis, or discover that there is enough water on the lunar surface to support a space colony. Hopefully the ISRO will be able to further expand its space program, despite critics of India’s government, who wish to have the bulk of the space exploration funds reallocated to social welfare programs.

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