APOTD: Ghost Nebula

APOTD: Molecular Cloud in Monoceros

APOTD: Soap Bubble Nebula

APOTD: Saturn's Glowing Aurora

APOTD: Tectonics on Enceladus

APOTD: A Star Making Waves

And Now, Neil deGrasse Tyson Dances To Michael Jackson

Astronomers Believed to Have Found First Rogue planet

In Other Neil deGrasse Tyson News...

APOTD: Late Afternoon SHadows at Endeavour Crater on Mars

Does New Data Challenge Giant Impact Theory?

Sometimes referred to as "the big splat" or "the big splash" hypothesis, the giant impact hypothesis is currently the most widely accepted explanation for the formation of Earth's only moon. According to this theory, sometime in our planet's distant past -as in, around 4.6 billion years ago- Earth was struck by a Mars-sized object dubbed Theia. This impact resulted in the ejection of a portion of material from the Earth's surface, which, along with Theia's remains, eventually coalesced to form the moon we see today. While there are, of course, several popular alternate explanations for the formation of our moon, none of them are as well supported by either physical observations or experimental results as the Giant impact theory; hence it's place of prominence on the issue.

One of the methods of testing the giant impact theory is to compare the isotope structure of basic elements found within rocks both on the moon and here on Earth. Because the the number of neutrons contained within each elemental isotope's nucleus can change, finding, say, an oxygen isotope with same atomic structure to be present in both samples, is a strong indicator that the samples in question originated from the same place. Which is exactly what previous analysis of lunar materials have shown.

But if 40% of the moon is made of the remains of the hypothetical object known as Theia, as is proposed by the giant impact theory. Then one would expect to eventually find some variance in the isotope structure of elements found in materials on the moon vs those on Earth, as those originating from Theia would presumably have been slightly different. But so far, that isn't the case. In fact, a recent analysis conducted by geochemists led by Junjun Zhang at the University of Chicago in Illinois, together with a colleague at the University of Bern in Switzerland, found, not only oxygen isotopes, but that also titanium isotopes taken from lunar materials, were identical to those found on Earth, which is a significant result. Because, while oxygen isotopes on each body could have been homogenized as a result of the formation process (meaning, oxygen isotopes originating from Theia cold basically have been "burnt off" and replaced) the high boiling point of titanium makes the same explanation an unlikely one for the presence of identical titanium isotopes.

So if the Giant impact hypothesis is correct, Thia really was a thing, and it's remains now account for 40% of the material on the moon, then why haven't we found any pieces of it yet?

The answer, of course, could be as simple as scientists having over estimated the size of Theia, that we merely haven't managed to collect a sample of it's remains yet, or some other variable or detail that we have yet to discover. But while it's an absolute certainty that the details of the Giant impact theory will change over time as new discoveries are made, and I think instances like this are both interesting and important examples of how the scientific process works. I think it's unlikely that this single data set will lead to the dethroning of the theory, and I'm personally not even convinced that it's a significant contradiction of previous findings, as the giant impact theory still accounts for more observed physical effects both on the Earth as well as the moon, than any of the alternate lunar formation theories around today.

-CAINE-

VIA: ScienceNOW

Herschel's Revisit of The Pillars of Creation

Alright, let's take a break from the SOPA/Internet censorship debacle, for something that isn't depressing and awful. The ESA's Herschel space observatory's revisit of the Eagle Nebula, or "Pillars of Creation" as it has been dubbed.


In 1995, NASA's Hubble Space Telescope took an iconic image of the Eagle nebula, dubbed the "Pillars of Creation," highlighting its finger-like pillars where new stars are thought to be forming. Now, the Herschel Space Observatory has a new, expansive view of the region captured in longer-wavelength infrared light.

The Herschel mission is led by the European Space Agency, with important NASA contributions.

The Eagle nebula is 6,500 light-years away in the constellation of Serpens. It contains a young, hot star cluster, NGC6611, visible with modest backyard telescopes, which is sculpting and illuminating the surrounding gas and dust. The result is a huge, hollowed-out cavity and pillars, each several light-years long.

The new Herschel image shows the pillars and the wide field of gas and dust around them. Captured in far-infrared wavelengths, the image allows astronomers to see inside the pillars and structures in the region. Herschel's image also makes it possible to search for young stars over a much wider region, and come to a much fuller understanding of the creative and destructive forces inside the Eagle nebula.

VIA: Herschel Space Observatory

The Growing Evidence for Mars' Watery Past

From questioning the probability of life of distant worlds, we turn to evidence of life, past or present, on worlds within our own solar system. Beginning with a look at the mounting evidence suggesting that Mars may, at the very least, have once been home to one of the key elements to the development of life as we understand it, Water.

In 1877, Italian astronomer Giovanni Schiaparelli, was the first to suggest that water may have once flowed on the Martian surface, after observing what he described as canals or "Canali", crisscrossing the planet's surface. Years later, in 1895, astronomer Percival Lowell, concluded that Schiaparelli's canals, must have been the work of a once great Martian civilization. Though we all now know that no such civilization ever existed on the red planet, and that even the canals themselves don't actually exist. Today, the consensus amongst planetary scientists still seems to be that Mars was once a wet world, much more similar to our own than it is today.

Observations made in recent years during various missions to Mars, have revealed, amongst other things, the presence of Jarosite -a mineral formed in the presence of highly acidic water- as well as gypsum, and other water-based minerals on the Martian surface. In 2008, the Pheonix lander confirmed the presence of water ice just beneath the soil in the planet's southern hemisphere. And in August of last year, images from the HRISE camera on board the Mars Reconnaissance orbiter, seemed to suggest that small amounts of salt water might still be seeping out from just beneath the planets soil.



A series of dark trails were observed radiating down from the edges of steep slopes of Mars' Newton Basin crater in the planet's southern hemisphere. Evidence suggested those lines may have been created by small amounts of salt water -lying frozen on or just beneath the soil- melting in the heat of the sun, and then trickling down the basin slopes. However, no one actually saw the water itself and instruments on board the MRO also failed to detect the presence of water in the Martian atmosphere. So the actual cause of those mysterious dark lines, remains inconclusive.


But the most recent, and what is being described as the most unambiguous evidence yet seen for the presence of liquid water in Mars' past, came in December of last year with the announcement that the Opportunity rover had discovered a small vein of Gypsum (seen in the false-color image to the left) just above the bedrock around the rim of Mars' Endeavor crater. Unlike previous detections of the mineral in the loose sands of various dunes, this newly found deposit -which is only 16 - 20 inches long, and about the width of a human thumb- was found in a fixed state, right where it was originally formed. A fact which Opportunity's principal investigator Steve Squyres, referred to as a; "slam-dunk story that water flowed through underground fractures in the rock,".

Normally, this would be the part where I warn you not to get to excited about the implications of such findings. And like any other new scientific discovery, this one will require multiple confirmations before it truly becomes an accepted fact. But it does, to my completely uneducated eye, seem as though the Phoenix rover's latest find is in fact another major step towards the absolute confirmation of Mars' watery past. Which would obviously have profound implications where the potential for life on the red planet -past or present- is concerned. But then again, I know as much about geology, as I do the ancient Mongolian art of fish-juggling. Which is to say nothing, since I just made that whole fish-juggling thing up. So I guess we'll just have to wait and see.

-CAINE-

Source: NASA/JPL
Image credits: NASA/JPL/Caltech/Cornel/ASU

Planetquest: A Historic Timeline of the Search for Exoplanets

If you'd like to learn more about the history of the search for exoplanets, check out this video from Planetquest, which gives a detailed account of exactly that. Chances are, the search for worlds outside our own solar system has been going on for longer than you think.

-CAINE-

You can checkout more videos from Planetquest HERE.

Exoplanets Everywhere: Kepler's ongoing Search for Other Worlds

When an object of a significant enough size passes in front of any star within Kepler's field of view (that's about 150,000, in case you were wondering), it causes a dip in the magnitude of light being emitted by the star. Revealing, not only the presence of any extrasolar planets around said star, but also the distance at which those planets orbit their parent star. This method of detection is commonly referred to as the transit method, and like any other method of detecting such planets, requires multiple observations for confirmation.


Found Orbiting the class G star Kepler 22, which is located around 600 light years from Earth in the Cygnus constellation. Planet Kepler 22b, was found to have a 290 day orbital cycle, which places the planet within what we have defined as the habitable zone of its parent star; which is lower in mass, and cooler than our own sun. But there's a catch. While the planet's diameter is estimated to be around 2.4 times that of Earth's, the actual mass of the planet is impossible to determine based on Kepler's observations alone. So it's impossible to say weather or not Kepler 22b is a rocky planet like Earth, or gaseous ball like Jupiter and Saturn. But if it is a world like our own, and assuming that it also has the proper atmosphere Kepler 22b would have an estimated average surface temperature of around 72 degrees F. Which would make it not only the most Earth-like world yet discovered, but also the most likely home for life as we know it outside of our own solar system. The prospect is obviously tantalizing.

To date, scientists have confirmed the existence of over 500 exoplanets * using Kepler, The Hubble Space Telescope, and various other observational techniques. As time goes on, even more discoveries will be made, and long term observations will slowly scratch all of the potential candidates off Kepler's list; possibly resulting in the confirmed discovery of several thousand more worlds orbiting stars light years away from our own. And while it will likely be some time before we ever definitively confirm that conditions on one those planets is conducive to life. The apparent abundance of stars with planetary systems would seem to suggest that it's only a matter of time before we do. And even if we can't say for certain that there's life on any of those planets, to think that we live in a time when discovering worlds in other star systems has become common place, is astonishing, to say the least.

-CAINE-

Source: NASA1, NASA2
Image credit: Kepler 11- NASA/Tim Pyle, Kepler 20e, 20 f, and 22b- NASA/Ames/JPL-Caltech

*The exact number of confirmed exoplanets was actually kind of hard to nail down, The Extrasolar Planets Encyclopedia claims 716. But the most common figure I found was in the 500-600 range.

Kepler Finds it's First Circumbinary Planet (Insert Obligatory Star Wars Refernce Here)

NASA's Kepler mission has announced the first direct detection of a circumbinary planet – a planet orbiting two stars- in a binary star system designated Kepler-16, located 200 light-years from Earth. While potential planets have previously been detected in other binary systems, Kepler-16b, as this newest exoplanet is now known, is the first confirmed planet to have been observed orbiting both it's parent stars.

A binary star system, as the name suggests, is a system with two stars orbiting around a common center of mass. Because from our vantage point on Earth, each of the two stars regularly passes in front of the other during their orbit, Kepler-16 is classified as an eclipsing binary.

Observations of Kepler-16 showed a drop in light from the system, not only when the stars eclipsed one another, as expected, but also a when neither star was eclipsing the other, indicating the presence of a much smaller 3rd object orbiting around them. By measuring the gravitational tug applied to the stars by this third objects, scientists were able to estimate it's mass, and Kepler-16b, as the new planet is now known, is believed to be a cold, uninhabitable world, about the size of Saturn, comprised of gas and rock.

Though Kepler-16b may be a cold, gaseous world -incapable of harboring any Jedi resistance fighters -or even sand people. As Kepler's Principal investigator William Borucki points out, the confirmation of a planet orbiting in a binary system - which are much more common than the single star system in which we reside-

"confirms a new class of planetary systems that could harbor life," and "Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."


-CAINE-

Source: NASA.gov
VIA: GGB on tumblr

NASA Finds Possible Proof of liquid Water on Mars

Earlier this month, NASA sent out a press release along with a series of images taken by the HRISE camera on board the Mars Reconnaissance orbiter showing a series of dark trails radiating down from the edges of steep slopes of Mars' Newton Basin crater, located on the planet's southern hemisphere. These trails first begin to appear and grow throughout the warmer months on the planet, and then recede as temperatures drop in the winter. Because the temperature in this particular area is too warm to allow for the creation of carbon dioxide frost, researchers concluded that the the most likely candidate behind the unusual markings were deposits of salt water, either on or just beneath the planet's surface, thawing and draining down the slopes with the changing of the seasons.

While it is generally accepted that Mars once had liquid water, possibly even an ocean flowing on it's surface, and the existence of water ice just beneath the planet's soil has been confirmed in various regions. These strange dark trails in the martian sand represent the best evidence to date that liquid water could in fact still exist on the red planet. Which would of course greatly increase the odds that Mars is also potentially host to at least microbial life.

However, while the images are compelling. The argument they make as proof of flowing water, is little more than circumstantial. As the water itself has yet to be directly observed or detected, and an attempt to confirm it's presence using the Compact Reconnaissance Imaging Spectrometer for Mars on board the MRO, was unsuccessful. Which could either mean that the water isn't there, it evaporates too quickly to detect, or that there simply isn't enough of it present in the atmosphere for it to be detected at all. Only time and further observation will tell for sure.

-CAINE-

Source:NASA

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