>O2 HUB >> Two dying stars reborn as one ( video)

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2 dying stars reborn as 1

CfA astronomers have found a pair of white dwarf stars orbiting each other once every 39 minutes. In a few million years, they will merge and reignite as a helium-burning star. In this artist’s conception, the reborn star is shown with a hypothetical world. Credit: David A. Aguilar (CfA)
White dwarfs are dead stars that pack a Sun‘s-worth of matter into an Earth-sized ball. Astronomers have just discovered an amazing pair of white dwarfs whirling around each other once every 39 minutes. This is the shortest-period pair of white dwarfs now known. Moreover, in a few million years they will collide and merge to create a single star.

“These stars have already lived a full life. When they merge, they’ll essentially be ‘reborn’ and enjoy a second life,” said Smithsonian Mukremin Kilic (Harvard-Smithsonian Center for Astrophysics), lead author on the paper announcing the discovery.
Out of the 100 billion stars in the , only a handful of merging white dwarf systems are known to exist. Most were found by Kilic and his colleagues. The latest discovery will be the first of the group to merge and be reborn.
The newly identified binary star (designated SDSS J010657.39 – 100003.3) is located about 7,800 light-years away in the constellation Cetus. It consists of two white dwarfs, a visible star and an unseen companion whose presence is betrayed by the visible star’s motion around it. The visible white dwarf weighs about 17 percent as much as the , while the second white dwarf weighs 43 per cent as much. Astronomers believe that both are made of helium.

CfA astronomers have found a pair of white dwarf stars orbiting each other once every 39 minutes. In a few million years, they will merge and reignite as a helium-burning star.

The two white dwarfs orbit each other at a distance of 140,000 miles – less than the distance from the to the Moon. They whirl around at speeds of 270 miles per second (1 million miles per hour), completing one orbit in only 39 minutes. The fate of these stars is already sealed. Because they wheel around so close to each other, the white dwarfs stir the space-time continuum, creating expanding ripples known as gravitational waves. Those waves carry away orbital energy, causing the to spiral closer and closer together. In about 37 million years, they will collide and merge.
When some collide, they explode as a supernova. However, to explode the two combined have to weigh 40 percent more than our Sun. This white dwarf pair isn’t heavy enough to go supernova. Instead, they will experience a second life. The merged remnant will begin fusing helium and shine like a normal star once more. We will witness starlight reborn.
This binary white dwarf was discovered as part of a survey program being conducted with the MMT Observatory on Mount Hopkins, Ariz. The survey has uncovered a dozen previously unknown white dwarf pairs. Half of those are merging and might explode as supernovae in the astronomically near future.

Provided by Harvard-Smithsonian Center for Astrophysics (news : web)

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>Google’s aims for Solar System-Wide WiFi

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The International Space Station as seen in its...Image via Wikipedia

Our solar system is big. Annoyingly so.
It’s so big that when it comes to communicating at these distances, even light speed doesn’t cut it. Transmitting data from the Earth to, say, a probe in orbit around Neptune takes about four hours. For a species that hopes to one day colonize our little space neighborhood and bring our information society in tow, this raises a range of communication hurdles. Aside from light’s newfound lugubriousness, the physical infrastructure of any interplanetary communication system would always be in flux as data relay stations duck and bob between the sun, planets, moons, and miscellaneous other celestial crumbs.
Sending a simple email between planets would be like playing a multimillion mile long game of croquet where all the hoops move at different speeds.
A loose coalition of smarty pantsinati have considered this problem for more than three decades. Chief among them has been Vint Cerf, often dubbed as one of “the fathers of the Internet” and current Google Chief Internet Evangelist. In 2009, Google unveiled a new interplanetary internet protocol developed by a team led by Cerf. The system compensated for these solar-system sized variables via a Delay- and Disruption-Tolerant Network (DTN). DTN is a networking architecture originally developed for the military that can function even when no clear end-to-end path is available.
DTNs stand in contrast to Transmission Control Protocol / Internet Protocol (TCP/IP), which is the standard the traditional internet is based on. Whereas TCP/IP assumes it will be able to transmit data over a period of milliseconds and will attempt to transmit said data repeatedly until delivery is confirmed, DTN is designed to compensate for massive lag and limited energy resources. An interplanetary DTN would work by sending bundles of data via a chain of relay nodes positioned around the solar system that would store the bundles and forward them along to the next celestial middleman when a clear path becomes available. Some models call for sending multiple replicas of the same data along several pathways to increase the chances of the information reaching its target in a timely manner.
You’re still sending data through the metaphorical croquet match, but in the DTN version, all the hoops are aware of where the ball has to go and where all the other moving hoops are and will forward the ball accordingly.

This interplanetary internet (IPN) isn’t just theoretical chalk talk either, it has already entered real world testing. DTN protocols are being utilized by the International Space Station as well as between various research labs around the world. And Google has even conducted a long range DTN test (80 light seconds, around 15 million miles) via a repurposing of NASA’s EPOXI spacecraft (formerly known as “Deep Impact”).
In an interview with NetworkWorld, Cerf describes the Google’s initiative to bring a standard internet architecture to the Final Frontier starting this year:

So during 2011, our initiative is to “space qualify” the interplanetary protocols in order to standardize them and make them available to all the space-faring countries. If they choose to adopt them, then potentially every spacecraft launched from that time on will be interwoven from a communications point of view. But perhaps more important, when the spacecraft have finished their primary missions, if they are still functionally operable — they have power, computer, communications — they can become nodes in an interplanetary backbone. So what can happen over time, is that we can literally grow an interplanetary network that can support both man and robotic exploration.

As the growing family of space nations fling more of their machines and flying laboratories farther into the cosmos, they will also—envisions Cerf—be adding hubs to the newly standardized space web. This new IPN will evolve space technology beyond the limitations of traditional point-to-point radio links allowing for more complex missions in need of a richer communication environment.
Additionally, as humans follow our machines into the farther reaches of the solar system, this will help cut down on the inevitable psychological detachment. And let’s be honest, is the ability to go where no person has gone before even worth it if you can’t brag about it on Facebook?

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