Planets – Page 11 – astroengine.com

Mars Can Be A Fuzzy Planet

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.

Where is Planet X? Where is Nemesis?

Before Pluto was discovered, the world’s astronomers were captivated by the possibility of finding another massive planet beyond the orbit of Neptune. In 1930, Pluto was discovered lurking in what was considered to be the edge of the Solar System. However, it quickly became apparent that Pluto was tiny; it wasn’t the Planet X we were looking for. For the last 80 years, astronomers have been looking for a large planet that might go to some way of explaining interplanetary features such as the “Kuiper Cliff”, but Planet X has not been found. Unfortunately, the word “Planet X” has now become synonymous with conspiracy theories and doomsday, almost as notorious as the word “Nemesis”.

Nemesis is another unanswered question hanging over Solar System evolution: does the Sun have a binary twin? Is there a second, dim, hidden “sun” stalking it’s brighter counterpart from over a light year away? Some scientists have come forward to suggest that the existence of a hypothetical second sun — embodied as a brown dwarf or red dwarf — could explain some cyclical effects here on Earth (i.e. mass extinctions occurring with a strange regularity). Naturally, the discussion about Nemesis (like the discussion about the possibility of a massive Planet X) is purely academic, and only based on indirect observations and anecdotal evidence. Just because they might exist, doesn’t mean they do.

In a publication recently published to the arXiv database, one Italian researcher has dusted off this topic and asked a very basic question: Can we constrain the possible locations of Nemesis and/or Planet X if they did exist? His results are fascinating…
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40% More Solar Energy For Opportunity

Good news for Mars Exploration Rover Opportunity, a windy day on the Martian surface has cleared a layer of dust off its solar panels.

Opportunity is currently trundling across the undulating dunes of Meridiani Planum on its way to Endeavour crater, a destination it wont reach for another two years. It needs all the energy it can muster. So, like the fortuitous gust of wind that gave Spirit a 3% boost in energy in February, Opportunity has received what may appear to be a small hurricane in comparison. This gust of wind shifted so much dust caked on the rover’s solar panels, the robot has had an energy increase of 40%.

As of Sol 1850 (April 7, 2009), Opportunity’s solar array energy production has increased to 515 watt-hours. Atmospheric opacity (tau) remains elevated at around 0.95. The dust factor has improved to 0.642, meaning that 64.2 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health with a rested actuator and extra energy. — NASA Opportunity updates

Since Opportunity arrived on Mars five years ago until April 7th, the tenacious rover has travelled 15,114 meters (9.39 miles). For a mission that was only slated to last three months, that’s not a bad distance its clocked up.

Source: NASA

Naming Pluto: The Trailer

I can’t emphasise enough how much I love this short film. It may only be 13 minutes long, but it is as small as it is mighty, much like the dwarf planet itself.

“Naming Pluto” documents the adventure of how Pluto got its name. Inevitably with most astronomical studies, there can be some controversy surrounding the naming of celestial objects, often depending on traditional naming protocol and who made the discovery first. The naming of Pluto on the other hand appears to take on a more natural tact, starting with a conversation in 1930 involving a little girl named Venetia Phair and her grandfather, over breakfast in Oxfordshire.

Father Films have just released a trailer for their magnificent film, giving you a taster as to what to expect. I had the pleasure of watching and reviewing a copy late last year, and I was blown away by the accuracy, wonder and history that can be packed into 13 minutes (note that the DVD has extras included, extending the content to 40 minutes). I fell in love with Pluto all over again – suddenly the fact that the IAU had demoted the planet to a dwarf planet (and then to a plutoid) didn’t matter any more. Written, directed and produced by Ginita Jimenez, Naming Pluto is in the true spirit of the International Year of Astronomy, capturing the excitement surrounding a tiny member of the Solar System with excellence. I wholeheartedly recommend this short film, it needs to be in your DVD collection! Patrick Moore is also at his best, giving the proceeds his unique style. And don’t just take it from me, Astronomy Now has also given the film a highly enthusiastic review.

Check out the Naming Pluto Facebook events page for more information »

You can purchase a copy of the DVD and poster from the Father Films website.

For more, check out my reviews of Naming Pluto on the Universe Today and Astroengine.com.

Could Extraterrestrial Genes Be Like Ours?

DNA and amino acids. Not just a terrestrial thing? (©CG4TV)

This is probably one of the biggest questions that hang over science fiction story lines: Will extraterrestrials have any resemblance to Life As We Know It™? To be honest, to toy with the thought of anything other than carbon-based life is pure conjecture, just because there might be some other form of life (such as silicon-based creatures), doesn’t mean there is (doesn’t mean there isn’t, either). So, here we are with the only form of life we know and understand, carbon-based life that was somehow spawned via a crazy mix of amino acids and some astronomical or terrestrial event that sparked the formation of prokaryotes (a.k.a. the simplest single-celled speck of life) some 4 billion years ago.

So we have an understanding of what formed life on Earth, perhaps if we look for the traces of evidence that evolved into Life As We Know It™ we can gauge whether extraterrestrial life has-formed/is-forming/will-form elsewhere in the observable Universe. From simulations of Earth evolution, scientists have predicted that 10 types of amino acids should form with the planet. These 10 amino acids are found inside the proteins of all living things on Earth. The same 10 amino acids have been found inside meteorites. Therefore, we already have a connection with the amino acids we find here on Earth and amino acids found in chunks of rock from elsewhere in the Solar System.

Now, a group of Canadian researchers have found that the same 10 amino acids are readily available elsewhere in the cosmos. Does this mean the components for life are common, not only on Earth, in the Solar System, but also in the Milky Way (and beyond)? It looks like it…
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Return of the Bouncing Boulder: Debris After a Martian Landslide

The debris after a landslide on Mars (NASA/HiRISE/Stuart Atkinson)

Mars is far from being geologically active when compared with the Earth, but it isn’t geologically dead either. In a stunning visual study by Stuart Atkinson over at Cumbrian Sky, he has done some desktop detective work on high-resolution HiRISE images of the Martian surface and turned up some astounding images. One scene shows a huge chunk of material, slumped down a slope, but in the detail are the familiar divots etching out the tracks of bouncing boulders after being disturbed by the Martian avalanche…
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Listening Out for the Magnetospheres of Habitable Exoplanets

Searching for Earth-like exoplanets (© Mark Garlick) — Searching for Earth-like exoplanets (© Mark Garlick*)

Is there a new way to hunt for habitable Earth-like exoplanets? According to a US Naval Research Laboratory researcher there is an obvious, yet ingenious, way of listening for these worlds. Like most Earth-like exoplanet searches, we are looking for characteristics of our own planet. So what do we need to survive on Earth? Obviously we need water and the correct mix of oxygen with other atmospheric gases, but what about the magnetic bubble we live in? The Earth’s magnetosphere protects us from the worst the Sun can throw at us, preventing the atmosphere from being eroded into space and deflecting life-hindering radiation.

Although we have yet to develop sensitive enough radio telescopes, it may be possible in the future to detect the radio waves generated as charged particles in stellar winds interact with Earth-like exoplanetary magnetospheres. If there’s a magnetosphere, there may be a protected atmosphere. If there’s an atmosphere, perhaps there’s life being nurtured below…

*This image is copyright Mark A. Garlick and has been used with permission. Please do not use this image in any way whatsoever without first contacting the artist.
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What Will Happen When the Sun Turns into a White Dwarf?

Strong tidal interactions are thought to shred any asteroids or comets as they get too close to a white dwarf (NASA)

All the way back in January, I had the great fortune to attend the American Astronomical Society’s (AAS) conference in Long Beach, California. I had a lot of fun. However, between the free beer and desperately searching for wireless Internet signal, I also did some work. During my travels, I spent some time browsing the poster sessions, trying to get inspiration for an article or two. You’d think that when presented with hundreds of stunning posters that inspiration wouldn’t be that far away. However, I was repeatedly frustrated by information overload and defaulted to a clueless meander up and down the pathways walled with intense science debates.

But then I saw it, right at the end of one of the poster walls, a question that got my imagination bubbling: “Will The Sun become a Metal Rich White Dwarf After Post Main Sequence Evolution?” The Sun? After the Main Sequence? Metal rich? To be honest, these were questions I’d never really pondered. What would happen when the Sun turns into a white dwarf? Fortunately, I had Dr John Debes to help me out with the answers…
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Welcome to my Sinkhole, Premium Martian Real Estate

A sinkhole in Tractus Fossae, created by tectonic activity (HiRISE/NASA)

It might not look like much from space, but this depression in the Martian landscape might be considered to be a priceless feature when viewed by future Mars colonists.

In December 2008, the Mars Reconnaissance Orbiter (MRO) flew silently over the Tharsis bulge, the location of a series of ancient volcanoes. The High Resolution Imaging Science Experiment (HiRISE) captured what appears to be a deep hole. This kind of feature has been seen before, like a Martian pore, deep and foreboding. Usually these sinkholes aren’t as deep as they look, but they are deeper than the surrounding landscape. They are also similar to their terrestrial counterparts in that they have very steep sides (unlike the gentle, eroded slopes of crater rims) and they are caused by a lack of material below. On Earth, sinkholes often form due to water flowing beneath, removing material, causing the overlying rock/soil to slump, forming a sudden hole. In the example above, the sinkhole (or “collapse pit”) was caused by tectonic activity. In this case, it is likely that the material dropped into a void left over by magma-filled dykes (lava tubes from old volcanoes).

A stretched and image processed version of the sinkhole; the bottom of the hole is visible (HiRISE/NASA)

The result is a hole with very steep sides. It has been suggested that these sink holes may be useful to future Mars colonists, as they can use the natural feature for shelter. On Mars, humans would be subject to an increased dosage of radiation (due to the tenuous Martian atmosphere and lack of a global magnetic field), so it is preferable to find any form of natural shelter to build your habitat. The depth of this kind of sinkhole will afford some protection, and drilling into the cavern side would be even better. Perhaps even put a dome over the top? No need to build walls around your building then. Also, there’s the interesting–if a little frightening–prospect of accessing underground lava tubes. Therefore, colonists won’t need to dig very far to create a subterranean habitat with all the radiation protection they’ll ever need (the insulation would also be impressive).

Although this scenario might be a little far-fetched, and probably only suitable for an established human presence on Mars (after all, the numerous valleys would probably suffice for most permanent habitats drilled into cliff faces), it does go to show that the current missions in orbit around Mars are doing a great job at seeking out some possible housing solutions for our future Mars settlers…

Source: HiRISE, Marspedia

A Short Message for Kepler, from Astroengine.com…

The Delta II ignition: Kepler begins its mission on Friday at 10:49pm EST (© United Launch Alliance) — The Delta II ignition: Kepler began its mission on Friday at 10:49pm EST (© United Launch Alliance)

In the 17th Century, Johannes Kepler defined the laws of planetary motion around our star. Now the Kepler space telescope will define the motion of alien worlds around distant stars. Go find us some exoplanets!

I saw this image on The Write Stuff blog at the Orlando Sentinel, and I had to share. It is the moment of ignition of the Delta II rocket from Space Launch Complex-17B at Cape Canaveral Air Force Station, just before lift-off of NASA’s Kepler mission.

For more information and the original image (this one was slightly adjusted to remove compression artefacts), check out The Write Stuff »