Saturday, June 1, 2013

Storms from orbit and other space and astronomy news

For this past week's news, I point out a connection between two stories, one in which NASA observed storms on Earth from orbit, and another which describes storms on exoplanets, again observed by NASA from orbit.

First, NASA Television on YouTube reports on The Oklahoma Storms As Seen From Space on This Week @NASA.

Also, NASA Administrator Charlie Bolden received updates on the important work being on done at the agency's California centers, , a New Crew Prepares for Launch to the International Space Station, and a look at Dream Chaser Flight Simulations. These and other stories on This Week @NASA.
NASA Television on YouTube also has the next story, ScienceCasts: Big Weather on Hot Jupiters.

Astronomers using NASA's Spitzer Space Telescope are making weather maps of an exotic class of exoplanets called "hot Jupiters." What they're finding is wilder than anything we experience here in our own solar system.
More space and astronomy news from the week that was over the jump.

NASA Television on YouTube: Kepler Update on This Week @NASA

This week, the Kepler science team announced the spacecraft was in a Thruster-Controlled Safe Mode. The root cause was undetermined but the proximate cause appears to be an attitude error caused by a malfunction in Kepler's reaction wheel 4, one of the telescope's pointing mechanisms. The team has since put the telescope in what's known as a Point Rest State, to minimize fuel usage while the investigation continues. Though no decisions have been made about the fate of the mission, the team notes that even if data collection were to end, Kepler has collected substantial quantities of data that should yield a string of scientific discoveries for years to come. Also, Living Off Earth, Future of Human Space Exploration, Garver briefed on Future Technologies, J-2X prepared for gimbal tests, Bolden checks out Aero Tech, Dreamchaser's arrival, Hangout with Star Trek cast and more!
DarkSyde on Daily Kos includes more general space and science news in This week in science: Perspective.

Now, the rest of the news arranged from the farthest reaches of space and time to the surface of the Earth.

PhysOrg: Physicists suggest possible existence of other kinds of dark matter
By Bob Yirka
May 24, 2013
A team of Harvard University physicists has proposed the possible existence of a type of dark matter not described by current physics models. In their paper published in the journal Physical Review Letters, the team suggests it's possible that not all dark matter is cold and collision-less.
If true, it would mean there could be whole dark galaxies out there, undetectable, yet as real as those we can see with the naked eye. Much more research will have to be done in this area before adding such types of dark matter to models in general use, of course. Until then, it will remain an abstract theory.
University of California via Science Daily: Detection of the Cosmic Gamma Ray Horizon: Measures All the Light in the Universe Since the Big Bang
May 24, 2013
How much light has been emitted by all galaxies since the cosmos began? After all, almost every photon (particle of light) from ultraviolet to far infrared wavelengths ever radiated by all galaxies that ever existed throughout cosmic history is still speeding through the Universe today. If we could carefully measure the number and energy (wavelength) of all those photons -- not only at the present time, but also back in time -- we might learn important secrets about the nature and evolution of the Universe, including how similar or different ancient galaxies were compared to the galaxies we see today.

That bath of ancient and young photons suffusing the Universe today is called the extragalactic background light (EBL). An accurate measurement of the EBL is as fundamental to cosmology as measuring the heat radiation left over from the Big Bang (the cosmic microwave background) at radio wavelengths. A new paper, called "Detection of the Cosmic ?-Ray Horizon from Multiwavelength Observations of Blazars," by Alberto Dominguez and six coauthors, just published today by the Astrophysical Journal -- based on observations spanning wavelengths from radio waves to very energetic gamma rays, obtained from several NASA spacecraft and several ground-based telescopes -- describes the best measurement yet of the evolution of the EBL over the past 5 billion years.
JPL/NASA via PhysOrg: Galaxies fed by funnels of fuel
May 24, 2013
Computer simulations of galaxies growing over billions of years have revealed a likely scenario for how they feed: a cosmic version of swirly straws.

The results show that cold gas—fuel for stars—spirals into the cores of galaxies along filaments, rapidly making its way to their "guts." Once there, the gas is converted into new stars, and the galaxies bulk up in mass.

"Galaxy formation is really chaotic," said Kyle Stewart, lead author of the new study appearing in the May 20th issue of the Astrophysical Journal. "It took us several hundred computer processors, over months of time, to simulate and learn more about how this process works." Stewart, who is now at the California Baptist University in Riverside, Calif., completed the majority of this work while at NASA's Jet Propulsion Laboratory in Pasadena, Calif.
NASA via Science Daily: Hidden Population of Exotic Neutron Stars
May 23, 2013
Magnetars -- the dense remains of dead stars that erupt sporadically with bursts of high-energy radiation -- are some of the most extreme objects known in the Universe. A major campaign using NASA's Chandra X-ray Observatory and several other satellites shows magnetars may be more diverse -- and common -- than previously thought.

When a massive star runs out of fuel, its core collapses to form a neutron star, an ultradense object about 10 to 15 miles wide. The gravitational energy released in this process blows the outer layers away in a supernova explosion and leaves the neutron star behind.

Most neutron stars are spinning rapidly -- a few times a second -- but a small fraction have a relatively low spin rate of once every few seconds, while generating occasional large blasts of X-rays. Because the only plausible source for the energy emitted in these outbursts is the magnetic energy stored in the star, these objects are called "magnetars."
National Radio Astronomy Observatory via Science Daily: Accurate Distance Measurement Resolves Major Astronomical Mystery
May 23, 2013
Sometimes astronomy is like real estate -- what's important is location, location, and location. Astronomers have resolved a major problem in their understanding of a class of stars that undergo regular outbursts by accurately measuring the distance to a famous example of the type.

The researchers used the National Science Foundation's Very Long Baseline Array (VLBA) and the European VLBI Network (EVN) to precisely locate one of the most-observed variable-star systems in the sky -- a double-star system called SS Cygni -- at 370 light-years from Earth. This new distance measurement meant that an explanation for the system's regular outbursts that applies to similar pairs also applies to SS Cygni.

"This is one of the best-studied systems of its type, but according to our understanding of how these things work, it should not have been having outbursts. The new distance measurement brings it into line with the standard explanation," said James Miller-Jones, of the Curtin University node of the International Centre for Radio Astronomy Research in Perth, Australia.
NASA via Science Daily: Hubble Reveals the Ring Nebula’s True Shape
May 23, 2013
The Ring Nebula's distinctive shape makes it a popular illustration for astronomy books. But new observations by NASA's Hubble Space Telescope of the glowing gas shroud around an old, dying, sun-like star reveal a new twist.

"The nebula is not like a bagel, but rather, it's like a jelly doughnut, because it's filled with material in the middle," said C. Robert O'Dell of Vanderbilt University in Nashville, Tenn. He leads a research team that used Hubble and several ground-based telescopes to obtain the best view yet of the iconic nebula. The images show a more complex structure than astronomers once thought and have allowed them to construct the most precise 3-D model of the nebula.

"With Hubble's detail, we see a completely different shape than what's been thought about historically for this classic nebula," O'Dell said. "The new Hubble observations show the nebula in much clearer detail, and we see things are not as simple as we previously thought."

Daily Kos: Getting to Know Your Solar System (34): Rhea
by Troubadour
Saturn's moon Rhea is hard to know, like one of those people whose faces just refuse to stick in memory, but everything about it other than its appearance suggests a significant role in far future human events.  The second largest and second most massive moon of the system, and orbitally the closest to Titan, Rhea is a giant iceball with very similar features to its smaller neighbors Dione and Tethys, but is itself far less distinct than either.  While it has its own unique combination of features, no individual feature apart from its size strongly distinguishes it from the siblings it resembles, and its mediocrity in all but bulk properties makes it a somewhat rare topic.
McGill University (Canada) via Science Daily: Bacterium from Canadian High Arctic Offers Clues to Possible Life On Mars
May 23, 2013
The temperature in the permafrost on Ellesmere Island in the Canadian high Arctic is nearly as cold as that of the surface of Mars. So the recent discovery by a McGill University led team of scientists of a bacterium that is able to thrive at -15ºC, the coldest temperature ever reported for bacterial growth, is exciting. The bacterium offers clues about some of the necessary preconditions for microbial life on both the Saturn moon Enceladus and Mars, where similar briny subzero conditions are thought to exist.

The team of researchers, led by Prof. Lyle Whyte and postdoctoral fellow Nadia Mykytczuk, both from the Dept. of Natural Resource Sciences at McGill University, discovered Planococcus halocryophilus OR1 after screening about 200 separate High Arctic microbes looking for the microorganism best adapted to the harsh conditions of the Arctic permafrost.

"We believe that this bacterium lives in very thin veins of very salty water found within the frozen permafrost on Ellesmere Island," explains Whyte. "The salt in the permafrost brine veins keeps the water from freezing at the ambient permafrost temperature (~-16ºC), creating a habitable but very harsh environment. It's not the easiest place to survive but this organism is capable of remaining active (i.e. breathing) to at least -25ºC in permafrost."
There is one major story missing from this digest.  I'm giving it an entry of its own as I'm updating it with video from today.  Stay tuned.

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