Tim Peake set for first spacewalk by British astronaut

Tim Peake is to carry out the first ever spacewalk by a British astronaut, Nasa has confirmed.

Mr Peake and Nasa astronaut Tim Kopra will venture outside the International Space Station (ISS) on 15 January to replace a failed voltage regulator.

Mr Peake launched on a Russian rocket on 15 December to begin a six-month stay on the orbiting outpost.

This will be the second spacewalk in under three weeks for Mr Kopra, who has flown into space once before, in 2009.

The two Tims will don their spacesuits and exit the US Quest airlock to replace an electrical box known as a Sequential Shunt Unit (SSU), which regulates voltage from the station's solar arrays.Its failure on 13 November last year compromised one of the station's eight power channels.

The unit is relatively easy to replace and can be removed by undoing one bolt. Once this task is complete, the spacewalkers will deploy cables in advance of new docking ports for US commercial crew vehicles and reinstall a valve that was removed for the relocation of the station's Leonardo module last year.

Mr Peake supported a spacewalk on 21 December last year, in which Mr Kopra and station commander Scott Kelly moved a stalled component known as the "mobile transporter" on the outside of the ISS.

The Briton stayed inside the ISS, helping the Americans don their spacesuits and monitoring their progress for mission control.

This time, he will be the one to get inside the Extravehicular Mobility Unit (EMU) - the spacesuit used by US and European astronauts on the station.

The spacewalk is scheduled to start at 12:55 GMT and last for six-and-a-half hours.Mr Peake and Mr Kopra were both crew members on the Russian Space Agency (Roscosmos) Soyuz flight that arrived at the ISS on 15 December. As such, they have trained closely with each other.

Mr Peake was selected by the European Space Agency in 2009, and is the first British astronaut to fly into space since Helen Sharman spent a week on the Soviet space station Mir in May 1991. Her flight was privately funded, under a venture known as Project Juno.The UK government has traditionally been opposed to human spaceflight, which has led other Britons to fly into space with Nasa - wearing the American, rather than UK flag on their uniforms.

Michael Foale, who hails from Louth in Lincolnshire, became the first British-born person to carry out a spacewalk when he stepped outside the shuttle Discovery on 9 February 1995.

Mr Foale flew on six Nasa shuttle missions, with extended stays on both Mir and the ISS. He has dual citizenship on account of his American-born mother.

Piers Sellers, who was born in Crowborough, flew on three space shuttle missions between 2002 and 2010. Over the course of six spacewalks, he accumulated 41 hours and 10 minutes of "extra-vehicular activity" time - the most of any UK-born astronaut.

Another UK-born Nasa astronaut, Nicholas Patrick, travelled into orbit on the Discovery shuttle in 2006.BBC

Gravitational waves from black holes detected

In a landmark discovery for physics and astronomy, scientists said Thursday they have glimpsed the first direct evidence of gravitational waves, ripples in the fabric of space-time that Albert Einstein predicted a century ago, reports AFP. When two black holes collided some 1.3 billion years ago, the joining of those two great masses sent forth a wobble that hurtled through space and reached Earth on September 14, 2015, when it was picked up by sophisticated instruments, researchers announced.
"Up until now we have been deaf to gravitational waves, but today, we are able to hear them," said David Reitze, executive director of the LIGO Laboratory, at a packed press conference in the US capital. Reitze and colleagues compared the magnitude of the discovery to Galileo's use of the telescope four centuries ago to open the era of modern astronomy. "I think we are doing something equally important here today. I think we are opening a window on the universe," Reitze said. The phenomenon was observed by two US-based underground detectors, designed to pick up tiny vibrations from passing gravitational waves, a project known as the Laser Interferometer Gravitational-wave Observatory, or LIGO. It took scientists months to verify their data and put it through a process of peer-review before announcing it on Thursday, marking the culmination of decades of efforts by teams around the world including some 1,000 scientists from 16 countries, according to the National Science Foundation, which funded the research.
Gravitational waves are a measure of strain in space, an effect of the motion of large masses that stretches the fabric of space-time -- a way of viewing space and time as a single, interweaved continuum. They travel at the speed of light and cannot be stopped or blocked by anything.
As part of his theory of general relativity, Einstein said space-time could be compared to a net, bowing under the weight of an object. Gravitational waves would be like ripples that emanate from a pebble thrown in a pond. While scientists have previously been able to calculate gravitational waves, they had never before seen one directly.
According to the Massachusetts Institute of Technology's (MIT) David Shoemaker, the leader of the Advanced LIGO team, it looked just like physicists thought it would.
"The waveform that we can calculate based on Einstein's theory of 1916 matches exactly what we observed in 2015," he told AFP.
"It looked like a chirp, it looked at something that started at low frequencies, sweeping very rapidly up over just a fraction of a second... up to 150 hertz or so, sort of near middle C on a piano."
The chirp "corresponded to the orbit of these two black holes getting smaller and smaller, and the speed of the two objects going faster and faster until the two became a single object," he explained. "And then right at the end of this waveform, we see the wobbling of the final black hole as if it were made of jelly as it settled into a static state."
The L-shaped LIGO detectors -- each about 2.5 miles (four kilometers) long -- were conceived and built by researchers at MIT and Caltech.
One is located in Hanford, Washington, and the other is in Livingston, Louisiana. A third advanced detector, called VIRGO, is scheduled to open in Italy later this year.
Tuck Stebbins, head of the gravitational astrophysics laboratory at NASA's Goddard Spaceflight Center, described the detector as the "one of the most complex machines built by humans."
Physicists said the gravitational wave detected at 1651 GMT on September 14 originated in the last fraction of a second before the fusion of two black holes somewhere in the southern sky, though they can't say precisely where.
Physicist Benoit Mours of France's National Center for Scientific Research (CNRS), described the discovery as "historic" because it "allows us to directly verify one of the predictions of the theory of general relativity."
Einstein had predicted such a phenomenon would occur when two black holes collided, but it had never before been observed. An analysis by the MIT and Caltech found that the two black holes joined about 1.3 billion years ago, and their mass was 29-36 times greater than the Sun. The wave arrived first at the Louisiana detector, then at the Washington instrument 7.1 milliseconds later.
The two instruments are 1,800 miles apart, and since both made the same reading, scientists consider their discovery confirmed. Accolades poured in from across the science world, as experts hailed a discovery that will help mankind better understand the universe.-- AFP

Liquid water found on Mars: NASA

   

A handout image made available by NASA on Sunday shows the dark narrow streaks called recurring slope lineae emanating out of the walls of Garni crater on Mars. The dark streaks are up to few hundred meters in length. They are hypothesized to be formed by flow of briny liquid water on Mars. AFP PHOTO

Liquid water has been observed on the planet Mars which makes it far more likely that life could be found there, US space agency NASA said yesterday, reports AFP from Washington.

“Mars is not the dry, arid planet we thought of in the past,” Jim Green, NASA’s planetary science director, told a press conference. “Under certain circumstances, liquid water has been found on Mars.”

Scientists have long speculated that there may once have been life on the Red Planet. The presence of liquid water makes it possible that life could currently exist there, NASA said.

"The really exciting thing about this is that our view of this ancient Mars, and the possibility of life originating on Mars, had been really about seeking chemical fossils of possible past life on Mars," said astronaut John Grunsfeld, who is also associate administrator of NASA's science mission directorate.

"The existence of liquid water on Mars -- even if it's super salty briney water -- gives the possibility that if there's life on Mars we have a way to describe how it might survive."

With several missions to Mars already in the planning stages, the question of whether there's life on the planet is now "a concrete one we can answer," Grunsfeld said.

The presence of water will also make it easier to send a manned mission to Mars, which NASA aims to do in the 2030s. "To be able to live on the surface, the resources are there," Grunsfeld said.

Water is "critical" he said, but the planet also offers other key elements like nitrogen which could be used to grow plants in greenhouses and the types of salts that could be used to make rocket fuel.

The announcement comes days before the blockbuster film "The Martian" opens in which Matt Damon manages to survive on his own after being left for dead with about a month's supply of food.

Scientists have long believed that water once flowed across the Red Planet and formed its valleys and canyons, but a major climate change about three billion years ago changed that.

"Today we're revolutionizing our understanding of this planet," Green said. "Our rovers are finding there's a lot more humidity in the air." The rovers have also found that the soil is more moist than anticipated.

In 2010 scientists observed dark streaks running down Martian slopes. They suspected that the streaks -- which would form in spring, grow by summer and then disappear by fall -- could be water.

"It took multiple spacecraft over several years to solve this mystery, and now we know there is liquid water on the surface of this cold, desert planet," said Michael Meyer, lead scientist for NASA's Mars exploration program.

"It seems that the more we study Mars, the more we learn how life could be supported and where there are resources to support life in the future." --AFP from Washington