Tagged: NASA

V838 Light Echo — The Movie

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What caused this outburst of V838 Mon? For reasons unknown, star V838 Mon suddenly became one of the brightest stars in the entire Milky Way Galaxy. Then, just a few months later, it faded.

A stellar flash like this has never been seen before — supernovas and novas expel a tremendous amount of matter out into space. Although the V838 Mon flash appeared to expel some material into space, what is seen in the above eight-frame movie, interpolated for smoothness, is actually an outwardly moving light echo of the flash. The actual time-span of the above movie is from 2002, when the flash was first recorded, to 2006.

In a light echo, light from the flash is reflected by successively more distant ellipsoids in the complex array of ambient interstellar dust that already surrounded the star. Currently, the leading model for V838′s outburst was the orbital decay and subsequent merging of two relatively normal stars. V838 Mon lies about 20,000 light years away toward the constellation of Monoceros, while the largest light echo above spans about six light years in diameter.

Thanks, Ursarodinia

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NASA debuts selfie of Earth

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NASA has unveiled a global selfie, a stunning mosaic of the planet Earth seen from outer space that was stitched together from tens of thousands of self-portraits taken by people from around the world.

The Earth images were created with more than 36,000 selfies that were submitted to NASA’s Jet Propulsion Laboratory this year on Earth Day, by people from 131 nations or regions. In the mosaic, self-portraits with blue backgrounds illustrate oceans, those with white backgrounds illustrate clouds, and photos with brown backgrounds illustrate continents.

Thanks, Ursarodinia

What would a functioning warp-drive ship look like?

Image by Mark Rademaker

Artist Mark Rademaker has unveiled a set of concept images imagining what a spaceship capable of traveling to other stars in a matter of months would really look like. Although it may look like something from the next science fiction epic and is unlikely to lift off anytime soon, his IXS Enterprise design is actually based on some hard science…

The idea comes from the work published by Miguel Alcubierre in 1994. His version of a warp drive is based on the observation that, though light can only travel at a maximum speed of 186,000 miles per second spacetime itself has a theoretically unlimited speed. Indeed, many physicists believe that during the first seconds of the Big Bang, the universe expanded at some 30 billion times the speed of light.

The Alcubierre warp drive works by recreating this ancient expansion in the form of a localized bubble around a spaceship. Alcubierre reasoned that if he could form a torus of negative energy density around a spacecraft and push it in the right direction, this would compress space in front of it and expand space behind it. As a result, the ship could travel at many times the speed of light while the ship itself sits in zero gravity, meaning the crew don’t end up as a grease stain on the aft bulkhead from the acceleration.

Unfortunately, the original maths indicated that a torus the size of Jupiter would be needed, and you’d have to turn Jupiter itself into pure energy to power it. Worse, negative energy density violates a lot of physical limits itself and to create it requires forms of matter so exotic that their existence is largely hypothetical.

In recent years, Dr Harold “Sonny” White of NASA’s Johnson Space Center has given the interstellar minded some cause for optimism by showing that even if the warp drive may not be possible, it may be much less impossible than previously thought. White looked at the equations and discovered that making the torus thicker, while reducing the space available for the ship, allowed the size of the torus to be greatly decreased, down to a width of 10 meters for a ship traveling ten times the speed of light.

According to White, with such a setup, a ship could reach Alpha Centauri in a little over five months, and oscillating the bubble around the craft reduces the stiffness of spacetime, making it easier to distort. This would reduce the amount of energy required by several orders of magnitude, making it possible to design a craft that, rather than being the size of Jupiter, is smaller than the Voyager 1 probe.

RTFA for another set of reasons why we ain’t seeing this anytime soon. Or maybe even later.

But, as David Szondy says in his article, “It doesn’t hurt to dream”.

In case you wondered what space smells like…?

This is Mike Hopkins – if you didn’t recognize him!

Most people probably assumed space was devoid of any sort of distinct musk — space is just a cold, dark, lifeless place, after all. But not so, says NASA astronaut Mike Hopkins, who recently returned to Earth after 166 days aboard the International Space Station.

Yesterday, in a tell-all, “ask-me-anything” Reddit interview, Hopkins spilled some of space’s secrets — including the fact that it smells.

“Space has a smell,” Hopkins wrote in one of his many responses. “And I don’t mean inside the space station,” he continued. “When a visiting vehicle docks with the space station, there is ‘space’ between the two vehicles. Once the pressure is equalized and the hatch is opened, you have this metallic ionization-type smell. It’s quite unique and very distinct.”

Among the other nuggets of space truth offered by Hopkins were the facts that: astronauts sweat and occasionally get nervous, the food isn’t that bad (his favorites were beef enchiladas and apricot cobbler), and that the he and his fellow ISS companions drink sweat to keep hydrated.

“The interesting part is that the sweat does go into the condensate system that gets recycled,” Hopkins wrote. “Eventually after the towels dry off and the water is recycled, it becomes drinking water.”

I know our culture inhibits casual reading of anything that even sounds like it’s somehow scientific. Still, I keep hoping.

Look to the sky this weekend — the Camelopardalids meteor shower

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Sky-watchers all across North America are in for a real treat in the early morning hours of May 24 – there’s a brand new meteor shower that may light up the night sky. Scientists aren’t sure yet how many shooting stars people may see, but the May Camelopardalids meteor shower could be at a dazzling one-per-minute rate.

This is the first time Earth will directly cross the dusty trails left behind by a recently discovered comet named Comet 209P/LINEAR. Discovered in 2004, this comet’s path has been slowly altered by Jupiter’s gravity over the last 200 years and the leftover dust will now cross Earth’s path. That’s good news for those in North America who – weather permitting – will have a front-row seat to see Mother Nature’s celestial display of fireworks. The meteors will appear from the northern constellation Camelopardalis…

“What’s really nice about this particular comet [209P/Linear] is that we’re going right smack in the middle of these dust trails and the meteors are going to be pretty slow,” Carl Hergenrother said. “They’re actually going to last maybe for a second or two. It’s going to look almost like slow moving fireworks instead of the usual shooting stars that we’re used to.”

The peak of the shower will be between 2 a.m. and 4 a.m. EDT, but Hergenrother said sky-watchers will still see meteors for several hours before and after those times. The biggest advice he has for people is to find a dark, safe place to get cozy and watch the stars…

NASA meteor expert Bill Cooke will host a live web chat from 11 p.m. to 3 a.m. EDT. To access the chat, log in and ask questions, go here. Enjoy.

Thanks, Mike

Citizen scientists hope to recapture, control, abandoned NASA satellite

The International Sun-Earth Explorer-3 — ISEE-3 for short — is a 35-year-old NASA space probe that’s been abandoned in space. Since 1981, the year in which it last executed a mission for the American space agency, the probe has been orbiting aimlessly.

Now, a group of citizen-scientists with Skycorp in Los Gatos, California want to recapture the spacecraft and put it back to work. And in signing a resent agreement with the group allowing them to at least try, NASA essentially said: “Hey, why not?”

To take on the mission, the group has raised some $143,000 on the crowd-funding site RocketHub. The attempt to contact and control ISEE-3 will be more than expensive; it will be extremely challenging. Scientists at Skycorp will need to develop retro software that can talk to technology from the 1970s.

At last check, the probe’s instruments were still functional, but there’s no guarantee the probe will be able to communicate with Earth. Still, Skycorp engineers are trying. The group has a team currently staked out at Arecibo Observatory, in Puerto Rico, attempting to reestablish contact with ISEE-3 as it makes its closest approach to Earth in the last 30 years…

If the probe responds to the scientists’ signal, the group will then attempt to control it — which they now have permission to do thanks to the agreement signed this week with NASA…

As part of the agreement, any new data collected by ISEE-3 with the help of Skycorp will be made public.

Go for it, gang!

Controlling the software on board ISEE-3 shouldn’t be anymore difficult than sorting the accounting practices of the Veterans Administration.

Nine maps showing ways climate change already affecting the United States

Temperature changes over the past 22 years (1991-2012) compared to the 1901-1960 average, and compared to the 1951-1980 average for Alaska and Hawai‘i. NOAA NCDC / CICS-NC.

This map is the simplest way to see global warming in action. Since the 19th century, average US temperatures have risen by 1.3°F to 1.9°F. (Note, though, there have been some fluctuations here and there: in the 1960s and 1970s, temperatures dipped, partly due to the cooling effect of sulfate pollution that was eventually cleaned up.)

Recent decades have been even hotter: since 1991, every region in the United States has been warming, with the biggest temperature increases occurring in the winter and spring.

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Martian Chiaroscuro

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Deep shadows create dramatic contrasts between light and dark in this high-resolution close-up of the martian surface.

Recorded on January 24 by the HiRISE camera onboard the Mars Reconnaissance Orbiter, the scene spans about 1.5 kilometers across a sand dune field in a southern highlands crater. Captured when the Sun was just 5 degrees above the local horizon, only the dune crests are caught in full sunlight. With the long, cold winter approaching the red planet’s southern hemisphere, bright ridges of seasonal frost line the martian dunes.

Thanks, Ursarodinia

Habitable Worlds

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Is Earth the only known world that can support life?

In an effort to find life-habitable worlds outside our Solar System, stars similar to our Sun are being monitored for slight light decreases that indicate eclipsing planets. Many previously-unknown planets are being found, including over 700 worlds recently uncovered by NASA’s Kepler satellite.

Depicted above in artist’s illustrations are twelve extrasolar planets that orbit in the habitable zones of their parent stars. These exoplanets have the right temperature for water to be a liquid on their surfaces, and so water-based life on Earth might be able to survive on them. Although technology cannot yet detect resident life, finding habitable exoplanets is a step that helps humanity to better understand its place in the cosmos.

If you’re thinking about leaving town, escaping whichever nutso nation you find yourself encapsulated within – consider a truly long-range journey.

I have no idea how to get there.

Thanks, Ursarodinia