Category: Science

When we look up into the night sky, we are also looking back in time. The light from the stars we see with our unaided eyes left those stars sometimes hundreds—if not thousands—of years ago. The arrival of Sirius in the winter skies always causes me to pause a moment and remember where I was and what I was doing nine years ago (the approximate time the light I’m now seeing left that star).

But if you look to the majority of bright, blue-white giants that form the Orion constellation, that light left well before you, me, our parents, grandparents, great grandparents, and in fact, this country were even born. I’ve marked up my photo from yesterday as a thought experiment.

As always, click for full size.

As NASA’s Cassini spacecraft soared past Saturn’s moon Titan, it recently caught a glimpse of bright sunlight reflecting off hydrocarbon seas. In the past, Cassini had captured, separately, views of the polar seas and the sun glinting off them, but this is the first time both have been seen together in the same view.

[Image: NASA/JPL-Caltech/Univ. Arizona/Univ. Idaho]

And to think there are people in this country who want to cut NASA’s funding.

If it were up to me, I’d increase it a hundred-fold.

Click to embiggen.

(Click to embiggen.)

From ARS Technica:

The latest discovery of Nasa’s Mars Curiosity rover is evidence of an ancient freshwater lake on Mars that was part of an environment that could potentially have supported simple microbial life.

The lake is located inside the Gale Crater and is thought to have covered an area that is 31 miles long and 3 miles wide for more than 100,000 years.

According to a paper published yesterday in Science Magazine: “The Curiosity rover discovered fine-grained sedimentary rocks, which are inferred to represent an ancient lake and preserve evidence of an environment that would have been suited to support a Martian biosphere founded on chemolithoautotrophy.”

Read 7 remaining paragraphs

A view that you’ll never see from Earth.

…why no one’s come knocking at our door!

I am reminded of an episode of the old Outer Limits where an air force fighter pilot and his wife are trapped in an alternate reality suspended in time—or a variation of the time dilation idea that was later used in an episode of the original Star Trek.

From iO9:

A new study suggests that small animals like birds and flies can observe movement on a finer timescale than larger creatures. Compared to us, many of these animals are able to perceive the world through a Matrix-like “bullet-time,” allowing them to escape larger predators.

We know that animals sense the world in any number of ways depending on the species. Dogs, for example, have awful eyesight and low horizon line. So instead of depending on their vision, they perceive the world primarily through sounds and smells. In addition, animals have varying dynamic ranges when it comes to their senses; dogs can hear up to 40 kHz, dolphins up to 150 kHz, and bats up to an astounding 212 kHz. Much of this has to do with the various ways animals have adapted to their roles as predators and prey.

Now it appears that there’s a kind of dynamic range that exists in vision, as well — and it has to do with the rate at which the world can be perceived. As the new study published in Animal Behavior shows, small animals like insects and small birds can take in more information in one second than a larger animal, like us bulky humans.

Indeed, all you need to do to get this impression is simply watch the way a small bird, like a budgie, twitches as it scans its surroundings. What looks like near-spasmodic behavior to us is an animal that’s essentially working at a faster “clock rate” (so to speak). To them, humans, or larger predators, appear to move in slow motion; we likely appear impossibly slow and cumbersome through those eyes.

To measure this rate of visual perception, a team from Trinity College Dublin (TCD), Ireland, used a technique called critical flicker fusion frequency — a system that measures the speed at which the eye can process light. It works by measuring the lowest frequency of flashing at which a flickering light source is perceived as a constant. The team looked at more than 30 species, including rodents, eels, lizards, chickens, pigeons, dogs, cats and leatherback turtles.

So, for instance, at the low end of the scale, deep sea isopods (or woodlice) could only see light turning off and on four times per second. At rates just slightly faster than that, these creatures perceive the light as being constantly on. Flies, on the other hand, have eyes that react to stimulus more than four times quicker than the human eye. Compared to us, flies see the world in slow motion.

(more)

National Geographic has created interactive maps of what would happen if all the ice melted on earth. The United States would be particularly hard hit as would sections of Euorpe and Southeast Asia. Africa and Australia would feel it the least.

The entire northeastern seaboard would disappear, along with all of Florida and the entire Gulf Coast. San Francisco’s hills would become a cluster of islands and the Central Valley an enormous bay (as it likely was in the distant past). The Gulf of California would extend northward past the latitude of the now-ennundated San Diego.

National Geographic reports:

The maps here show the world as it is now ,with only one difference: All the ice on land has melted and drained into the sea, raising it 216 feet and creating new shorelines for our continents and inland seas.

There are more than five million cubic miles of ice on Earth, and some scientists say it would take more than 5,000 years to melt it all. If we continue adding carbon to the atmosphere, we’ll very likely create an ice-free planet, with an average temperature of perhaps 80 degrees Fahrenheit instead of the current 58.

Click on any of the maps to see the full size version.

The entire surface of planet Mercury has been mapped. Detailed observations of the innermost planet’s surprising crust have been ongoing since the robotic MESSENGER spacecraft first passed Mercury in 2008 and began orbiting in 2011. Previously, much of the Mercury’s surface was unknown as it is too far for Earth-bound telescopes to see clearly. The above video is a compilation of thousands of images of Mercury rendered in exaggerated colors to better contrast different surface features. Visible are rays emanating from a northern impact that stretch across much of the planet, while about half-way through the video the light colored Caloris Basin–an ancient impact feature that filled with lava–rotates into view. MESSENGER has now successfully completed its primary and first extended missions.

I aced it!

Science and Technology Quiz.