And now, the case of the disappearing methane

First, as posted a few days ago, there was the mystery of seemingly missing methane on an exoplanet. Now there’s another methane-related riddle, on Mars. First detected in 2003, the gas is being continually produced, but the origin is still unknown. It could be either geological or biological, and is concentrated in three areas in the northern hemisphere, regions of previous volcanic activity and underground water ice. The amount also varies with the seasons, increasing in the spring, more so in the summer, peaking in autumn and then rapidly decreasing in winter. That pattern could fit with either still-occurring hydrothermal activity or biology, ie. microbes, or both.

The new puzzle though is why the methane has now been observed to remain in the atmosphere for less than a Martian year. It was expected to last longer, so something is destroying it relatively quickly, faster than expected for a photochemical process (destruction by sunlight). As stated in the article, perhaps chemicals from the soil, being alofted into the atmosphere by winds.

So both the origin and demise of the Martian methane are currently unknown. Hopefully more answers can come from the upcoming Mars Science Laboratory rover (Curiosity) and the ExoMars missions, both of which are equipped to analyse the methane in more detail…

Blog update

I’ve tweaked the blog a bit more, updating the header graphic a bit and switching to a white background. Also playing with the CSS for other minor tweaks, but I like the feel now. Will add more blogs to the blogroll and photos to the photo galleries as I have time… 🙂

The case of the missing methane

In our solar system, all of the gas giant planets have abundant methane in their atmospheres. It was expected that similar planets in other solar systems would also, but one has been found which doesn’t… the planet GJ 436b, about the size of Neptune, orbiting a star 33 light-years from Earth. Based on analysis by the Spitzer Space Telescope, it appears to have almost none, which is a mystery. It should be noted that methane on these types of planets is primordial methane, a very simple molecule, left over from the planets’ original creation. On small rocky planets like Earth and Mars (and it exists on both), it can be either geological or biological in origin. In the case of Mars, the origin is still uncertain.

Artist's conception. Credit: NASA/JPL-Caltech

The Great Red Spot in stunning detail

There is a great new blog post over at The Planetary Society Blog regarding a new, enhanced moasaic image of Jupiter’s Great Red Spot, from the original Voyager 1 images taken in 1979. New computer technology not available then has brought out amazing new details. The new enhancements were done by Björn Jónsson. It looks like a painting but is very real…! Larger hi-res version is here.

Credit: NASA/JPL. Image processing: Björn Jónsson

Bridges on the Moon

This is interesting; the Lunar Reconnaissance Orbiter has photographed the first known naturally forming bridges on the moon. Natural bridges on Earth usually result from wind and water erosion, so just how these ones formed on the airless moon isn’t clear yet, but a collapsed lava tube is thought to be the most likely answer.

Credit: NASA/Goddard/ASU