ikenbot:

Starry Winter Landscape

by Babak A. Tafreshi

Fresh snow fall has covered Zagros Mountains of Iran under a starry winter night. Light from the setting moon has illuminated the top of these mountains near Natanz in central Iran.

ikenbot:

A Hole in Mars

Credit: NASA, JPL, U. Arizona

Back in 2007, black spots were discovered on Mars that are so dark that nothing inside can be seen. Quite possibly, the spots are entrances to deep underground caves capable of protecting Martian life, were it to exist.

The unusual hole pictured above was found on the slopes of the giant Martian volcano Arsia Mons. The above image was captured three weeks ago by the HiRISE instrument onboard the Mars Reconnaissance Orbiter currently circling Mars.

The holes were originally identified on lower resolution images from the Mars Odyssey spacecraft, The above hole is about the size of a football field and is so deep that it is completely unilluminated by the Sun. Such holes and underground caves might be prime targets for future spacecraft, robots, and even the next generation of human interplanetary explorers.

fyeahuniverse:

^Picromerite

^{Picromerite has the formula K₂Mg(SO₄)₂.6(H₂O), this particular specimen was found in Werra Valley, North Hesse, Germany.}

^{(Image credit: Rob Lavinsky)}

Mesolimulus walchi (extinct arthropod) fossil and its track! It’s rare to have this kind of preservation, and very important to scientists.

(Photo by unforth on Flickr; approved to share)

(via crownedrose)

ikenbot:

Triton: The Outer Most Ocean in The Solar System

A new day dawns on Triton. It’s going to be a cold one, much like the last. And the one before that… and every day since the moon settled into its present orbit around Neptune. Even the volcanoes here spew out cold gases and liquid water rather than hot magma. But below the frigid surface, which registers a temperature of -235 °C, there’s something more clement: a liquid ocean.

At first glance, Triton seems to be just another icy moon – a featureless, barren world spinning around Neptune, the outermost planet of our solar system. But Triton is different.

For one thing, it orbits Neptune backwards, moving in the opposite direction to Neptune’s rotation. It’s the only large moon in the solar system to do so. Satellites can’t form in these “retrograde” orbits, so Triton must have begun life elsewhere before being captured by the gas giant. It looks a lot like Pluto, and probably came from the same place – the inner edge of the Kuiper Belt, close to Neptune.

The Voyager 2 spacecraft flew past Triton in 1989, sending back images of the moon’s frozen surface. They revealed signs of cryovolcanism – the eruption of subsurface liquids which quickly freeze when exposed to the cold of the outer solar system. As such, Triton joins a short list of worlds in the solar system known to be geologically active.

Its surface ice is unique, too: largely composed of nitrogen, with some cantaloupe-textured terrain, and a polar cap of frozen methane.

Continue..

crownedrose:

White Rim Sandstone Pinching Out 2 W/ Geology Annotated by wyojones on Flickr

Photo caption from photographer: “Dead Horse Point State Park, Utah.
A locally well known stratal pinch-out of the White Rim Sandstone which is the upper Member of the Permian Cutler Formation In the Paradox Basin of southeastern Utah.”

Click here to see a hi-res photo with labels.

Utah geology is awesome! If you ever have a chance to explore the state, don’t hesitate to do it!

(via geologise)

ikenbot:

Glacier Flows in Iceland

by Erlend Haarberg

An aerial view showing small streams flowing at the Langj kull glacier in Iceland.

[As seen on DailyMail’s ‘Iceland from the air: Incredible aerial pictures show the majesty of the country’s volcanic landscapes’]

crownedrose:

Dirty Science: What Makes Soil Become Dense?
An earthy activity brought to you by Science Buddies: Learn how compacted soil can affect local plants and animals, and how you can run experiments to test this!
Image: George Retseck

“Have you ever noticed how much work it is to dig a hole in really hard soil? It’s much easier to dig a hole in soft, loose soil. But why is that? Soil that is hard and dry is often compacted, which means that it has been packed down, making it denser and thereby difficult to penetrate. Soil that has become compacted is not only harder for you to dig a hole in, but it can also be much harder for a lot of other organisms, such as helpful earthworms, to survive in.”

Read more on Scientific American.

ikenbot:

Pacman & Pie charts

Astronaut Don Pettit, on board the International Space Station as a member of Expedition 30/31 tweeted this photo from space. He described it as: “Pac-man in Brazil as seen from ISS http://pic.twitter.com/0tP9EgoP.”