Unless you’ve been living in the Oort Cloud you’ve probably heard about the current travels of comet C/2012 S1 (aka ISON) through the inner solar system. Although this soon-to-be “sungrazing” comet was first spotted by astronomers Vitali Nevski (from Belarus) and Artyom Novichonok (Russia) on Sept. 21, 2012, it’s actually been on its way toward the Sun for much, much longer — possibly for the past several million years or so. But on November 28 at 1:38 p.m. EST, as many Americans are sitting down for their Thanksgiving Day dinners here in the U.S., ISON will make its closest pass around the Sun (called perihelion) and, while you won’t be able to see it in the sky at that point (it’s much too close to the Sun right now) our many eyes in the sky will be watching.
There’s been a lot of misinformation passed around the ‘net recently regarding ISON (as seems to be de rigueur whenever something astronomical is occurring) and I can’t stress enough that there’s no reason to be concerned about this comet’s visit. If anything, ISON should be the one worried — there’s still a chance that it won’t survive perihelion intact! In fact, some reports are suggesting that it already has broken up (which as yet has not been confirmed). So to answer some of the most common questions people have been asking about ISON, NASA has shared some video interviews with experts on the subject. Watch them below:
It’s been 15 years since the first piece of what we now know as the International Space Station left the surface of our planet. It was Russia’s Zarya module, launched aboard a Proton rocket on Nov. 20, 1998, and the U.S. followed suit two weeks later with the Unity module sent aboard the shuttle Endeavour. Since then, in what is truly an international effort, the Station was assembled piece by piece until its ultimate ‘official’ completion in 2011 (more research instruments and upgrades have been added since then, of course.)
Orbiting the planet 16 times every day and consistently occupied since 2000, the ISS is not only an invaluable space research lab but also a testament to what we humans can do when we cooperate successfully and focus our energies and abilities toward a common goal, overcoming the challenges of national politics, economic difficulties, and even the barriers of language and culture. It is a lofty achievement, but the work that is done there each day is for the benefit of everyone.
And don’t forget about the view! Our planet is quite beautiful from 260 miles up — and the video above, assembled from time-lapse photos taken from the ISS and edited by David Peterson, shows that wonderfully. See a collection of photos taken from the Space Station here.
“Station is truly an engineering marvel and a testament to what we can accomplish when we all work together. I think one of the most enduring legacies will be the international cooperation we have achieved in building and operating it. It has provided us the framework for how we will move forward as we explore beyond our home planet, not as explorers from any one country, but as explorers from planet Earth.”
– Kennedy Space Center Director Bob Cabana
Read more about the 15th anniversary of ISS here, and check out a cool infographic of Station facts and figures below:
Mars wasn’t always the cold, dry world that it is today — billions of years ago it likely looked a lot more like Earth, with seas and rivers of liquid water on its surface and a thick atmosphere with air and clouds. But something happened over the course of Mars’ history to transform it from a warm, wet world to a cold, desiccated desert planet, and while there are many viable suggestions as to what process is responsible, no verdict has yet been delivered.
This video, just released by NASA’s Goddard Space Flight Center, shows what Mars might have looked like four billion years ago. As the camera tracks back the clouds gradually disappear, the lakes and rivers turn to rubble-strewn plains and the skies change from blue to pale orange. As we rise above the dust clouds that roll across the planet, we see the first evidence of modern times: NASA’s MAVEN spacecraft, flying high overhead to investigate the mystery of a lost Mars.
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Go get some extra socks handy because this new image of Saturn is going to knock ‘em clean off your feet.
Seen in eclipse against the light of the Sun, Saturn and its rings seem to glow with a magical light in this picture, painstakingly assembled from 141 separate wide-angle images taken by the Cassini spacecraft on July 19, 2013. The view is over 400,000 miles wide and Cassini was on the night side of Saturn, almost a billion miles away.
And you know what’s even cooler? You’re in this image. We all are, in fact.
If you thought tails were just for comets and cats, this asteroid is about to prove you wrong.
On August 27 astronomers spotted an unusually fuzzy looking object in survey images taken with the Pan-STARRS telescope in Hawaii. The multiple tails were discovered in Hubble images taken on September 10, 2013. When Hubble returned to the asteroid two weeks later, its appearance had totally changed — it looked as if the entire structure had swung around!
While this object is on an asteroid-like orbit, it looks like a comet, and is sending out tails of dust into space. Because nothing like this has ever been seen before, astronomers are scratching their heads to find an adequate explanation for its mysterious appearance.
Just when scientists thought they had a tidy theory for how the giant asteroid Vesta formed, a new paper from NASA’s Dawn mission suggests the history is more complicated.
If Vesta’s formation had followed the script for the formation of rocky planets like our own, heat from the interior would have created distinct, separated layers of rock (generally, a core, mantle and crust). In that story, the mineral olivine should concentrate in the mantle.
However, as described in a paper in this week’s issue of the journal Nature, that’s not what Dawn’s visible and infrared mapping spectrometer (VIR) instrument found. The observations of the huge craters in Vesta’s southern hemisphere that exposed the lower crust and should have excavated the mantle did not find evidence of olivine there. Scientists instead found clear signatures of olivine in the surface material in the northern hemisphere.
Every few days or so I like to check the “Close Approaches” page of JPL’s Near-Earth Object Program, just to see what sorts of cosmic objects are whizzing by our planet; how big they are, when they’ll come, and how far they’ll (hopefully!) miss us by. Most of them are relatively small asteroids several dozen meters in width, passing us at a few tens of lunar distances (avg. distance to the Moon is about 370,000 km/235,000 miles or so.) Every now and then, though, something passes us by closely, coming within a handful of lunar distances — or even closer than the Moon itself. These events spark my interest as they remind us that there’s a lot of bits of solar system out there, and sometimes (while we’re busy doing other things) the bigger pieces get unnervingly close.
Yesterday JPL’s NEO specialists Don Yeomans and Paul Chodas posted an article about some “surprising discoveries” of three recently-found asteroids — all of which are of considerable size (two ~19 km/12 miles wide and one 2 km) and the third of which passes by closely enough to be considered “potentially hazardous” (as opposed to merely “near Earth”). Curious? Read on…
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