Mars Chaos

The Ariadnes Colles region of Mars (ESA)

Of all the places I’d want to visit on Mars, this would be high on my list. After travelling to the bottom of Hellas Planitia (for the thick atmosphere and possibly finding liquid water) and the summit of Olympus Mons (for the view), I’d be sure to have a scout around Ariadnes Colles, in the southern hemisphere (pictured above).

The Ariadnes Colles region may not be a household name, but looking at these new high resolution images coming from the Mars Express orbiter, I can’t help but be impressed…
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Mars Can Be A Fuzzy Planet

The summit of Pavonis Mons (NASA)

This strange image was captured by the Mars Reconnaissance Orbiter’s (MRO) camera–the amazing High Resolution Imaging Science Experiment (HiRISE)–as it passed over one of the largest volcanoes in the Solar System, Pavonis Mons.

Located near the equator of Mars, atop the Tharsis bulge, Pavonis Mons is the second highest volcano after the huge Olympus Mons (towering over the Martian surface 27 km high). Pavonis Mons is still much higher than anything the Earth can muster, towering 14km into the atmosphere (compare that with the altitude of Mt. Everest’s peak height of 8.85 km).

So why is this picture so blurry? Is HiRISE suffering a malfunction? Did mission control send the wrong commands? Actually, HiRISE is working just fine. It’s the dust-covered surface that’s blurred.

As the ancient volcano is reaching so high into the Martian atmosphere, the air becomes very thin. The atmosphere was already thin; the average ground level atmospheric pressure is less than 1% of the Earth’s. At Pavonis Mons’ peak, the atmospheric pressure is ten-times thinner. Therefore any wind at these altitudes is extremely weak.

The extreme planet-wide dust storms that regularly engulf Mars dump huge quantities of dust on the top of the Martian volcanoes, but when the dust settles, there’s nothing to transport it elsewhere. Therefore, the thick layer of fine material remains where it is, tickled by the light-weight winds, rarely moving.

In the high resolution image, you can see some resolved features such as the odd impact crater and small ripples. Other than that, it’s a thick, smooth dust blanket that covers the Pavonis Mons summit, hiding any interesting geology for below, giving the impression any images of the summit are out of focus…

For more, check out The Blurry Summit of Mars’ Pavonis Mons on the Universe Today.

Mystery Blob Detected 12.9 Billion Light Years Away

The Himiko object, the most massive object ever discovered in the early universe (M. Ouchi et al.)

Take a good look, this is one of the most mysterious, massive objects ever discovered in the cosmos. We don’t really know what it is, but this thing is huge, spanning 55,000 light years across (the approximate radius of our Milky Way). What makes this all the more intriguing is the fact that this object formed only 800 million years after the Big Bang and it is 10 times more massive than the next biggest object observed in the early Universe. But what is it?
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Could Active-SETI Learn From… Twitter?

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The Search for Extraterrestrial Intelligence (SETI) has been an ongoing endeavour for the last 50 years. Detecting radio communications from an alien civilization would be the most profound event in mankind’s history; its effect would change the way we view our origin and our place in the Universe. It could mean that far from “being alone” we could be existing in a cosmic ecosystem, where life is more common than not and advanced extraterrestrial civilizations are no longer science fiction. A positive SETI signal would affect us globally; science, religion, society, daily life would alter radically.

Unfortunately, SETI is currently drawing up blanks. Apart from one or two inconclusive signs, it looks like we live in a dead part of the galaxy. Life As We Know It™ is an Earth-only affair. Who knows, we might be searching for another five decades and still be no closer to answering the question “are we alone?

Not to be too downhearted, scientists have been trying to make our presence felt by reversing SETI; we’ve been Messaging Extraterrestrial Intelligence (METI, a.k.a. “Active-SETI”) ever since we attached a plaque depicting the human form and a handy galactic map to Earth to the side of the Pioneer probes in the 1970s. Now we send a variety of radio signals to the stars in the hope of attracting ET’s attention.

But what signal do we send? Do we send a message with only good stuff from Earth? Or should we send a more gritty message, detailing our flaws as well as achievements? What actually makes a “good” METI signal in the first place?

Perhaps SETI could take some advice from the evolving social media scene, after all, when done right, there’s no more efficient way of conveying a clear message via 140 characters or less…
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Brown Dwarfs: “Over-Achieving Jupiters” not “Failed Stars”

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Why is the term “failed star” synonymous with brown dwarfs? On the one hand, brown dwarfs lack the mass to sustain nuclear fusion in their cores. On the other hand, who said brown dwarfs were trying to be stars? Who ever said that becoming a star was the pinnacle of stellar living? Perhaps brown dwarfs are perfectly happy the way they are. In a world of equality and political correctness, brown dwarfs could be viewed as “over-achieving Jupiters”, or gas supergiants
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An Explanation For Solar Sigmoids

A coronal sigmoid as imaged by the XRT instrument on Hinode (JAXA)

Sigmoids in the solar corona have been studied for many years, but little explanation of their formation or why they are often the seed of powerful solar flares have been forthcoming. Using high-resolution X-ray images from the Japanese-led solar mission Hinode (originally Solar-B), solar physicists have known that these very hot S-shaped structures are composed of many highly stressed magnetic flux tubes filled with energized plasma (also known as ‘fibrils’), but until now, little was known about the formation and flare eruption processes that occur in sigmoids.

Now, a team of solar physicists from the University of St Andrews believe they have found an answer using powerful magnetohydrodynamic (MHD) computer models, aiding our understanding of coronal dynamics and getting us one step closer to forecasting space weather…
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Are Brown Dwarfs More Common Than We Thought?

A brown dwarf plus aurorae (NRAO)

In 2007, a very rare event was observed from Earth by several observers. An object passed in front of a star located near the centre of the Milky Way, magnifying its light. Gravitational lensing is not uncommon in itself (the phenomenon was predicted by Einstein in 1915), but if we consider what facilitated this rare “microlensing” event, things become rather interesting.
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