Scorching hot Venus may have once had oceans… of carbon dioxide

Radar image of the northern hemisphere of Venus, taken by the Magellan spacecraft. Radar is necessary to see through Venus’ perpetual cloud cover. Image Credit: NASA/JPL
Radar image of the northern hemisphere of Venus, taken by the Magellan spacecraft. Radar is necessary to see through Venus’ perpetual cloud cover. Image Credit: NASA/JPL

The continued exploration of the planets and moons in our Solar System have revealed many strange things, including that Earth is not the only place with oceans and seas. Mars once had lakes and possibly oceans in the distant past, some of the icy moons in the outer Solar System such as Europa and Enceladus currently have subsurface oceans and seas, and Titan has seas and lakes of liquid methane/ethane on its surface. That’s weird enough, but now there’s a new twist: Venus may have had oceans of liquid carbon dioxide (CO2) in the past.

Continue reading →

Image Gallery: rocky hill in Pahrump Hills

Rocky hill in the Pahrump Hills area. Image Credit: Hortonheardawho/JPL/NASA
Rocky hill in the Pahrump Hills area. Larger image versions here. Image Credit: Hortonheardawho/JPL/NASA

This is a great image to start 2015 with: a new panoramic view of a small but very rocky hill in the Pahrump Hills area on Mars, taken by the Curiosity rover. You can see the larger versions here on Flickr. When you zoom in, you can see a lot of small lighter-coloured patches on rocks in the right side of the panorama and even a small “cave” with a flow of sand coming out of it. There’s a lot of geology and history here; as we’ve seen before, the scenery is very reminiscent of the American southwest. Thanks to Hortonheardawho from the Mars Forum for his excellent panorama stitched together from individual Curiosity images.

Continue reading →

Tilted aquaplanets might still be habitable, study suggests

Artist’s conception of an ocean-covered aquaplanet. Image Credit: Christine Daniloff/MIT
Artist’s conception of an ocean-covered aquaplanet. Image Credit: Christine Daniloff/MIT

With so many exoplanets now being discovered on a regular basis by astronomers, the focus has turned to what number of them might be habitable for some kind of life. For life as we know it at least, that depends on a number of factors, including being in the “habitable zone” of stars, where liquid water could exist on the surfaces of smaller, rocky planets like Earth. It has been thought that planets with extreme axial tilts, even horizontal to the plane of their orbits, would be less likely to host life. But now a new study suggests that they could still be quite habitable, if they are covered by oceans.

Continue reading →

Kepler finds ‘super-Earth’ exoplanet in first discovery of new mission

Artist’s conception of super-Earth HIP 116454b. Credit: David A. Aguilar (CfA)
Artist’s conception of super-Earth HIP 116454b. Image Credit: David A. Aguilar (CfA)

The Kepler space telescope has found its first new exoplanet, a “super-Earth,” of its secondary mission phase. The discovery adds to a current tally of 996 confirmed exoplanets and 4,183 planetary candidates already found by the revolutionary planet-hunting telescope.

Continue reading →

Has Curiosity found evidence for ancient microbial life on Mars?

pia17595-figa-unannotated1
Curiosity image from Yellowknife Bay, where the potential microbial mat features were first seen in sandstone rocks. Gillespie Lake Member is the series of flat rocks in the central-left area of the image. Image Credit: NASA/JPL-Caltech/MSSS

There is a report which has been getting a lot of attention the past few days (in addition to the methane and organics found), that the Curiosity rover may have found evidence for ancient microbial life itself on Mars. Specifically, microbial mats, which are common on Earth. The report comes from noted geobiologist Nora Noffke, who has been studying images sent back by the rover since it landed in 2012.

Continue reading →

Image Gallery: fog in Valles Marineris

Water fog in the Valles Marineris canyons. Image Credit: ESA/DLR/FU Berlin
Water fog in the Valles Marineris canyons. Image Credit: ESA/DLR/FU Berlin

After yesterday’s exciting news about the Curiosity rover finding methane and organics on Mars, here is a reminder that the planet is rather Earth-like in other ways too, such as having water clouds and fog. This well-known image is from the Mars Express spacecraft, showing dense fog filling canyons in Valles Marineris, the giant canyon system that dwarfs Earth’s Grand Canyon. Even in Mars’ thin atmosphere, clouds and fog can still often easily form.

Continue reading →