Beyond Verses Headlines

Beyond Verses

Saturday, August 13, 2011

NASA Opens New Office for Deep Space Missions

Monday, June 20, 2011

Bubbles in our outskirts?!

NASA's Voyager probes are truly going where no one has gone before. Gliding silently toward the stars, 9 billion miles from Earth, they are beaming back news from the most distant, unexplored reaches of the solar system.

Mission scientists say the probes have just sent back some very big news indeed.

It's bubbly out there.




According to computer models, the bubbles are large, about 100 million miles wide, so it would take the speedy probes weeks to cross just one of them. Voyager 1 entered the "foam-zone" around 2007, and Voyager 2 followed about a year later. At first researchers didn't understand what the Voyagers were sensing--but now they have a good idea.

"The sun's magnetic field extends all the way to the edge of the solar system," explains Opher. "Because the sun spins, its magnetic field becomes twisted and wrinkled, a bit like a ballerina's skirt. Far, far away from the sun, where the Voyagers are now, the folds of the skirt bunch up."

When a magnetic field gets severely folded like this, interesting things can happen. Lines of magnetic force criss-cross, and "reconnect". (Magnetic reconnection is the same energetic process underlying solar flares.) The crowded folds of the skirt reorganize themselves, sometimes explosively, into foamy magnetic bubbles.

"We never expected to find such a foam at the edge of the solar system, but there it is!" says Opher's colleague, University of Maryland physicist Jim Drake.

Theories dating back to the 1950s had predicted a very different scenario: The distant magnetic field of the sun was supposed to curve around in relatively graceful arcs, eventually folding back to rejoin the sun. The actual bubbles appear to be self-contained and substantially disconnected from the broader solar magnetic field.

Energetic particle sensor readings suggest that the Voyagers are occasionally dipping in and out of the foam—so there might be regions where the old ideas still hold. But there is no question that old models alone cannot explain what the Voyagers have found.

Says Drake: "We are still trying to wrap our minds around the implications of these findings."

The structure of the sun's distant magnetic field—foam vs. no-foam—is of acute scientific importance because it defines how we interact with the rest of the galaxy. Researchers call the region where the Voyagers are now "the heliosheath." It is essentially the border crossing between the Solar System and the rest of the Milky Way. Lots of things try to get across—interstellar clouds, knots of galactic magnetism, cosmic rays and so on. Will these intruders encounter a riot of bubbly magnetism (the new view) or graceful lines of magnetic force leading back to the sun (the old view)?

Old and new views of the heliosheath. Red and blue spirals are the gracefully curving magnetic field lines of orthodox models. New data from Voyager add a magnetic froth (inset) to the mix. Credit: NASA

The case of cosmic rays is illustrative. Galactic cosmic rays are subatomic particles accelerated to near-light speed by distant black holes and supernova explosions. When these microscopic cannonballs try to enter the solar system, they have to fight through the sun's magnetic field to reach the inner planets.

"The magnetic bubbles appear to be our first line of defense against cosmic rays," points out Opher. "We haven't figured out yet if this is a good thing or not."

On one hand, the bubbles would seem to be a very porous shield, allowing many cosmic rays through the gaps. On the other hand, cosmic rays could get trapped inside the bubbles, which would make the froth a very good shield indeed.

So far, much of the evidence for the bubbles comes from the Voyager energetic particle and flow measurements. Proof can also be obtained from the Voyager magnetic field observations and some of this data is also very suggestive. However, because the magnetic field is so weak, the data takes much longer to analyze with the appropriate care. Thus, unraveling the magnetic signatures of bubbles in the Voyager data is ongoing.

"We'll probably discover which is correct as the Voyagers proceed deeper into the froth and learn more about its organization," says Opher. "This is just the beginning, and I predict more surprises ahead."

For more information on Voyager findings, pictures and videos, check the following link: 

Credit: NASA


Friday, June 3, 2011

NASA | Swift Finds Most Distant Gamma-ray Burst Yet

On April 29, 2009, a five-second-long burst of gamma rays from the constellation Canes Venatici triggered the Burst Alert Telescope on NASA's Swift satellite. As with most gamma-ray bursts, this one -- now designated GRB 090429B -- heralded the death of a star some 30 times the sun's mass and the likely birth of a new black hole.
"What's important about this event isn't so much the 'what' but the 'where,'" said Neil Gehrels, lead scientist for Swift at NASA's Goddard Space Flight Center in Greenbelt, Md. "GRB 090429B exploded at the cosmic frontier, among some of the earliest stars to form in our universe."
Because light moves at finite speed, looking farther into the universe means looking back in time. GRB 090429B gives astronomers a glimpse of the universe as it appeared some 520 million years after the universe began.
Now, after two years of painstaking analysis, astronomers studying the afterglow of the explosion say they're confident that the blast was the farthest explosion yet identified -- and at a distance of 13.14 billion light-years, a contender for the most distant object now known.
Swift's discoveries continue to push the cosmic frontier deeper back in time. A gamma-ray burst detected on Sept. 4, 2005, was shown to be lie 12.77 billion light-years away. Until the new study dethroned it, GRB 090423, which was detected just six days before the current record-holder, reigned a distance of about 13.04 billion light-years. All of these gamma-ray bursts were among the first 500 detected by Swift.



For more information:
GRB (Gamma-ray burst)
http://en.wikipedia.org/wiki/Gamma-ray_burst

And this is the Official NASA Swift Home Page
http://heasarc.nasa.gov/docs/swift/swiftsc.html 

Tuesday, May 24, 2011

NASA Announces STS-134 Wakeup Song Winners; Face In Space Totals

HOUSTON -- NASA announced the winners of its "Original Song Contest" after six weeks of public voting. The songs will awaken the STS-134 astronauts aboard space shuttle Endeavour during their ongoing mission. 

"Sunrise Number 1" by Jorge Otero and the band Stormy Mondays from Oviedo, Spain, earned first place. Shuttle Commander Mark Kelly, Pilot Greg H. Johnson, Mission Specialists Mike Fincke, Drew Feustel, Greg Chamitoff and Roberto Vittori of the European Space Agency will hear the song at 5:56 p.m. EDT on May 31 - the day before the crew returns to Earth. "Sunrise Number 1" received 787,725 votes, or 49.8 percent of the total ballots. 

"Dreams You Give" by Brian Plunkett from Halfway, Mo., earned second place with 612,959 votes, or 38.8 percent. It will wake the crew at 6:56 p.m. on May 30. 

The Original Song Contest received 1,350 entries for consideration, and NASA selected 10 songs as finalists. The public cast 1,581,531 votes for their favorite song from March 29 through May 16. To listen to the songs and see the all the results, visit: 


The winning songs also have videos. To view the video for "Sunrise Number 1," visit: 





To view the video for "Dreams you Give," visit: 


NASA also released the final tally of submissions to the Space Shuttle Program's "Face in Space" campaign for the STS-134 mission. Participants submitted 128,940 photos for uplink to Endeavour via the Mission Control Center at NASA's Johnson Space Center in Houston. The images will return to Earth through a data transmission, and contributors will be able to print certificates verifying their photos flew aboard Endeavour. 

More than 7,550 other photos already have been submitted to fly aboard the last shuttle mission targeted to launch July 8. Submissions will be accepted through the liftoff date. To take part in the STS-135 Face in Space campaign, visit:


And by the way, I participate :) so may be I found My name there :D

For more information about the Space Shuttle Program and the STS-134 mission to the International Space Station, visit:


For more information about the space station, visit:


Source         

Sunday, May 22, 2011

Radio Telescopes Capture Best-Ever Snapshot Of Black Hole Jets

WASHINGTON -- An international team, including NASA-funded researchers, using radio telescopes located throughout the Southern Hemisphere has produced the most detailed image of particle jets erupting from a supermassive black hole in a nearby galaxy.

"These jets arise as infalling matter approaches the black hole, but we don't yet know the details of how they form and maintain themselves," said Cornelia Mueller, the study's lead author and a doctoral student at the University of Erlangen-Nuremberg in Germany.

The new image shows a region less than 4.2 light-years across -- less than the distance between our sun and the nearest star. Radio-emitting features as small as 15 light-days can be seen, making this the highest-resolution view of galactic jets ever made. The study will appear in the June issue of Astronomy and Astrophysics and is available online.

Mueller and her team targeted Centaurus A (Cen A), a nearby galaxy with a supermassive black hole weighing 55 million times the sun's mass. Also known as NGC 5128, Cen A is located about 12 million light-years away in the constellation Centaurus and is one of the first celestial radio sources identified with a galaxy.

Seen in radio waves, Cen A is one of the biggest and brightest objects in the sky, nearly 20 times the apparent size of a full moon. This is because the visible galaxy lies nestled between a pair of giant radio-emitting lobes, each nearly a million light-years long.

These lobes are filled with matter streaming from particle jets near the galaxy's central black hole. Astronomers estimate that matter near the base of these jets races outward at about one-third the speed of light.

Using an intercontinental array of nine radio telescopes, researchers for the TANAMI (Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry) project were able to effectively zoom into the galaxy's innermost realm.

"Advanced computer techniques allow us to combine data from the individual telescopes to yield images with the sharpness of a single giant telescope, one nearly as large as Earth itself," said Roopesh Ojha at NASA's Goddard Space Flight Center in Greenbelt, Md.

The enormous energy output of galaxies like Cen A comes from gas falling toward a black hole weighing millions of times the sun's mass. Through processes not fully understood, some of this infalling matter is ejected in opposing jets at a substantial fraction of the speed of light. Detailed views of the jet's structure will help astronomers determine how they form.

The jets strongly interact with surrounding gas, at times possibly changing a galaxy's rate of star formation. Jets play an important but poorly understood role in the formation and evolution of galaxies. NASA's Fermi Gamma-ray Space Telescope has detected much higher-energy radiation from Cen A's central region.

"This radiation is billions of times more energetic than the radio waves we detect, and exactly where it originates remains a mystery," said Matthias Kadler at the University of Wuerzburg in Germany and a collaborator of Ojha. "With TANAMI, we hope to probe the galaxy's innermost depths to find out."

Ojha is funded through a Fermi investigation on multiwavelength studies of Active Galactic Nuclei.

The astronomers credit continuing improvements in the Australian Long Baseline Array (LBA) with TANAMI's enormously increased image quality and resolution. The project augments the LBA with telescopes in South Africa, Chile and Antarctica to explore the brightest galactic jets in the southern sky.

NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy, along with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden and the U.S.

The Australia Long Baseline Array is part of the Australia Telescope National Facility, which is funded by the Commonwealth of Australia for operation as a National Facility managed by the Commonwealth Scientific and Industrial Research Organization. 

For more information and images, visit:

Saturday, May 21, 2011

Dark Energy Confirmed Again!

"We all need to look into the dark side of our nature - that's where the energy is, the passion. People are afraid of that because it holds pieces of us we're busy denying." -Sue Grafton

No, not the dark side of our nature, just the dark side of nature! Because if all our Universe were made out of were atoms and photons, we wouldn't get a Universe that looks like ours.

What do I mean? Let's take a look.

(Image credit: MPA Garching and Volker Springel.)

The Universe starts off as a very smooth place, where regions that are denser or less densethan average are only something like 0.003% away from average. To put it in economic terms, if the average salary were $50,000 a year, the richest person would make about $3 extra, and the poorest person would make about $3 less than average.

But that's the early Universe. Over time, those richer, denser regions attract more and more matter, growing in size and scope.

(Animation credit: Center for Cosmological Physics, National Center for Supercomputer Applications, and Andrey Kravtsov (U. Chicago) and Anatoly Klypin (NMSU).)


Today, we see the very densest regions as being the places with the greatest concentrations of galaxies, and the least dense regions are devoid of almost all matter.

We can even still find galaxies merging today; evidence of the legacy of these small gravitational inequalities from when the Universe was billions of years younger than it is

(Image credit: NASA and The Hubble Heritage Team (STScI).)

But it isn't like we just get giant clumps of galaxies that fall in to one another, and collapse under gravity. As much as we like to pretend that gravity is the only thing that matters in the Universe, there's another force that's often just as important.

Don't believe me? Then think about the biggest, brightest, close object to you in the Universe. 300,000 times as massive as the planet Earth, the Sun's gravity is absolutely tremendous.

(Image credit: NASA/CXC/M.Weiss.)

And yet the Sun is less dense than the Earth is! That's because there's something holding the Sun up that the Earth doesn't have: radiation pressure!

All the nuclear fusion happening at the core of the Sun produces a gargantuan amount of energetic photons. It's so powerful that, at the Sun's surface, the outward pressure is enough to counteract the force of the Sun's gravity, and that's why the Sun doesn't contract or collapse.

And then we come to the Universe.

(Image credit: CCA Zurich.)

Sure, today, the Universe looks a lot like this. The pressure from radiation is totally negligible except in the hottest and densest of objects, like stars.

But go back in time, to when the Universe was very young, and radiation was of incredibleimportance! In fact, for the first 10,000 years of the Universe or so, it was even more important than matter! Which means, during this time, if you were matter trying to collapse under the influence of gravity, radiation pressure would bounce you back out!

(Wish I could find the image credit for this one!)

This is part of why the early Universe is so smooth, for certain. But this feature -- matter trying to collapse under the influence of gravity vs. radiation pressure pushing it back out -- creates a "wave" or "ripple" like you see above. You can see a dense region at the center, you can see it get sparser and sparser as you move away, and then it gets denser once again.

This feature, created by normal atoms (baryons) and radiation (photons), is known as anacoustic oscillation. Why? Because it's a pressure wave, just like sound is! The only difference is, this type of wave determines how galaxies group together.

(Image credit: Chuck Bennett and Nature.)

So if we go and measure how far apart the galaxies in the Universe are spaced from one another, we can figure out:

What percentage of the matter is normal matter,
What percent is dark (non-baryonic) matter, and
How quickly the Universe has expanded since, or what percent of the Universe is dark energy

It's a very clever way to do it, and it's a brilliant way to check our laws of gravity. If we're doing it correctly, and General Relativity is right, we should, by measuring these galaxies, see how the Universe has expanded from the Cosmic Microwave Background over billions of years to form galaxies, and then from those galaxies to our eyes.

(Image credit: NASA's WMAP and the Sloan Digital Sky Survey.)

Well, the WiggleZ team from Australia just released their results this week: the most comprehensive survey -- of 200,000+ galaxies -- designed to measure dark energy by this method.

Their results are a spectacular confirmation of the best prediction of our Universe: one where 70-75% of the energy is dark energy, and where the total amount of baryons is only about 4-5%, with the rest being dark matter. They also found, to the best of their measurements, that dark energy is, in fact, a cosmological constant, with no change over time and the correct equation of state. (I.e., it gives the right pressure/energy density combination to be a cosmological constant.)

Led by Warrick Couch and Michael Drinkwater, and also with scientists such as Chris Blake and Karl Glazebrook, the WiggleZ dark energy survey has been a smashing success, and I'm happy to report that the team appears to have done everything impeccably. Some good press coverage is available here and here, as well as the full press release here.)

The full WiggleZ team (as best as I can find) is pictured below.

And I'd like to say, on a personal note, I'm really impressed, and I'm really happy for all of this!

Most of you don't know this, but before I turned the bulk of my energies towards communicating and teaching science, I was offered a job at Swinburne, working with the WiggleZ team. (Check it out on the old job rumor page.) They were a great group, and they made the job decision an extremely difficult one for me, because I could tell they were doing exciting, top-notch science, and it's great to see it come to fruition like this, even if I wasn't a part of it. Every once in a while, I let my imagination wander to the life I would have had if I had taken it, and all I know is that it would be vastly different than the one I'm living now.

But who knew, more than four years ago when I made that decision, that I'd be telling thousands of you about their smashing success?!

This is another great success for dark matter, dark energy, and the standard big bang picture of the Universe, and yet another tremendous challenge for alternative theories to explain. All you have to do is measure how far apart galaxy pairs are, how that distance changes as the Universe expands, and that's one new way for you to measure dark energy,completely independently of supernovae!

Congratulations to the entire WiggleZ team, and to all of you for learning about the latest, greatest confirmation of the most mysterious force in the Universe! 

Sunday, May 15, 2011

NASA Clears Endeavour for Next-to-Last Shuttle Flight

At NASA
At NASA's Kennedy Space Center in Florida, space shuttle Endeavour awaits its final liftoff from Launch Pad 39A.
CREDIT: NASA


CAPE CANAVERAL, Fla. — NASA officials have given the space shuttle Endeavour a "go" to launch on its final space voyage Monday (May 16).
The shuttle is now scheduled to lift off from here at Kennedy Space Center (KSC)'s Launch Pad 39A at 8:56 a.m. EDT (1256 GMT). [Photos: Shuttle Endeavour's Final Mission]

We had "unanimous consent from the mission management team to press on with the launch countdown," mission management team chair Mike Moses said during a briefing today (May 14). "We should be in really good shape for launch Monday morning."
Weather forecasters predict a 70 percent chance the weather will cooperate for Endeavour's launch on Monday.
"Overall, it's looking promising for launch, with a 30 percent chance of KSC weather prohibiting launch," shuttle weather officer Kathy Winters said. The main concerns at launch time will be winds at the emergency landing site here at KSC, and the chance of a low cloud ceiling, she said.
This will be the shuttle's second launch try after an earlier attempt was foiled by a failed heater that insulates a critical power unit called an Auxiliary Power Unit (APU) on the shuttle.
Engineers replaced a faulty switch box that had sparked the heater problem, along with wiring to and from the box. [The People Behind Endeavour: Engineers Reflect on NASA's Youngest Shuttle]
Mission managers have "really high confidence" the problem is fixed now, Moses said. "In our minds we are good to go and we have no problems expected with this APU heater anymore in this count."
This will be the last mission for shuttle Endeavour, and the next-to-last flight of NASA's 30-year space shuttle program. Endeavour's goal is to deliver a $2 billion antimatter hunting experiment and a haul of spare supplies for the International Space Station.
Endeavour will spend about 16 days in orbit on a mission that includes four ambitious spacewalks to pack away the spare supplies and upgrade the exterior of the station.
Commander Mark Kelly will lead Endeavour's veteran crew of six astronauts. Kelly's wife, Congresswoman Gabrielle Giffords, D-Ariz., is expected to attend the launch in person despite having been shot in the head in January. Giffords is undergoing rehabilitation at a hospital in Houston.