shanmuga
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Miss this, and the next one’s in 2117
May 19th
KOLKATA: If you have a pair of sun goggles, get them dusted for a celestial event on June 6. Venus will crawl across the disc of the sun that day and it can be seen in Kolkata from sunrise till around 10am.
The event has generated tremendous interest across the world since the next transit will occur only in 2117.
As with a solar eclipse, do not look at the sun with naked eyes. “Since Venus will only cover 1/32 of the sun’s disc, looking the event with the naked eye is a strict no-no. You should use scientifically tested aluminized Mylar filter (sometimes called as solar goggles) or No.14 welder’s glass,” said MP Birla Planetarium director (research & academic) Debiprosad Duari.
Using exposed X-ray plates or smoked glass is very dangerous, he warns. “The best method is to project the sun’s image through a telescope or a pinhole camera on a screen or a plane white surface,” he says.
Venus’ transit is an extremely significant event because it was central to the evolution of the first concrete concept of the solar system and ushered in the modern era of astronomical observations for calculating some parameters of the solar system.
Kolkata will miss out the first half of the event as it will happen before sunrise.
“The event is quite rare. Once a transit occurs, it will happen again after a span of eight years. But thereafter a transit will not be seen for 105.5 years. Again after a pair of transits, the next one will happen after a gap of 121.5 years,” explained Duari.
On June 6, the transit will last for about 5 hours 40 minutes. The last part of it will be visible in India. For Kolkata, the transit will start around 3.40am.
The greatest transit – when the black dot of Venus can be seen at the innermost point of the disc of the sun – will occur at 7.02am. The transit will end at around 10.20am. The small disc of Venus will touch the Sun’s disc internally at 10.04am and will be completely out at 10.21am. On June 6, the sun will rise around 4.51am in Kolkata. Though the transit should be seen then onwards, realistically it can only be viewed properly around half hour later.First predicted by Johannes Kepler, the transit of Venus gave proof of Galileo Galilei’s sun-centered model of the solar system.
The entire event of the transit of Venus will be visible from eastern Australia, New Zealand, New Guniea, the Philippines, northern Asia, eastern China, Korea, Japan, the islands of the western Pacific Ocean, Hawaii, Russia, Alaska and north-west Canada. In the far north, the entire transit can also be seen, since the sun will not set. From eastern Canada, United States, the Central America, Caribbean and northwest south America where only the first part of the transit will be visible, before the sun sets down.
However, not all inferior conjunction results in a visible transit. This is because the orbital plane of Venus is inclined at an angle of 3.4 degree to the Earth-Sun orbital plane and Sun, Venus and Earth may not be in a straight line.
Source : http://timesofindia.indiatimes.com/city/kolkata/Miss-this-and-the-next-ones-in-2117/articleshow/13285044.cms
Testing Private Ship to the Space Station, and Wine, Too
May 18th
In space, how quickly does grape juice turn to wine?
Two California high school students hope to find out soon. Their experiment is one of 11 aboard a rocket scheduled to blast off early Saturday from Cape Canaveral, Fla., to the International Space Station. “We think it’s going to ferment faster,” said Max Holden, a ninth grader at Chaminade College Preparatory in West Hills, Calif.
But there is no guarantee that the seven-inch tube of yeast and grape juice will ever reach its destination.
The launching is a test flight of a spacecraft built by the Space Exploration Technologies Corporation, or SpaceX, of Hawthorne, Calif. The event is slightly historic: if all goes well, the ship will be the first operated by a private company, rather than the government, to supply the space station.
Erring on the side of caution, officials at NASA and SpaceX have stressed that the purpose of the mission is to shake out glitches. “I think there’s a significant chance the mission does not succeed,” said Elon Musk, chief executive of SpaceX.
The craft, a Falcon 9 rocket with a Dragon capsule on top of it, will carry more than 1,000 pounds of cargo, mostly food and clothing — items that NASA regards as no big loss should the launching fail.
The only scientific experiments on the mission are those devised by students as part of a program run by the National Center for Earth and Space Science Education. They will explore the effects of zero gravity, including whether medicines can slow bone loss and whether certain bacteria that eat plastic would thrive and eat greater amounts of plastic in space.
The liftoff, set for 4:55 Saturday morning, is timed to take place at the moment the launching pad lines up with the space station’s orbit. If weather or a technical problem keeps the rocket on the ground, SpaceX will have to wait until 3:44 a.m. Tuesday for the pad and orbit to line up again.
After reaching orbit, the Dragon capsule is to perform a series of test maneuvers. On the third day, it is scheduled to fly 1.5 miles under the space station to demonstrate its navigation and communication systems. If it passes the tests, NASA will give the go-ahead for the final approach on Tuesday, when Donald R. Pettit, a NASA astronaut, will use the space station’s robotic arm to grab the Dragon and pull it to a docking port.
If successful, the Dragon would be the first commercial spacecraft to visit the space station, and SpaceX would collect the remaining payments on a $396 million agreement with NASA to develop the cargo ship. SpaceX would then enter a $1.6 billion contract for a dozen cargo flights to the station.
If the flight fails, SpaceX would have to repeat the demonstration flight until it succeeds.
SpaceX has so far avoided the early failures that typically accompany a new rocket like the Falcon 9. The maiden flight, in June 2010, was almost flawless. The second flight — the first under the NASA agreement — was in December 2010, putting into orbit a Dragon capsule that successfully parachuted back to Earth.
The successes have, however, taken longer than anticipated. SpaceX originally predicted its first visit to the space station would be in 2009. The delays were not a big surprise, Mr. Musk said, given the complexities.
“Certainly, we would have hoped to have been further ahead,” he said, “but I wouldn’t have expected that with great confidence.”
For the students at Chaminade Preparatory looking forward to the winemaking experiment, the launching will be particularly exciting. If the capsule makes it to the space station, one of the astronauts there will mix the grape juice and yeast and let it ferment for five days.
Max Holden and his lab partner, Paige D’Andrea, a 10th grader, will perform the same experiment, and when the space wine is returned to Earth about a month later, they will compare the two.
“When we get it back, we’re going to get one of the priests to bless it,” said Nancy McIntyre, the director of the project for Chaminade, a Catholic school.
To figure out which one is more alcoholic, the students will not taste any of the fermented grape juice, but instead will measure the amount of carbon dioxide produced by the yeast.
SpaceX poised to dock with ISS
May 17th
New Delhi: SpaceX, owned by the billionaire Internet entrepreneur, Elon Musk , is all poised to be the first private company to send its own cargo ship to the International Space Station (ISS).
The space mission will begin before dawn Saturday (4:55 am, 0855 GMT) with the launch of the unmanned Dragon spacecraft aboard a Falcon 9 rocket from Cape Canaveral Air Force Station in Florida.
If all goes well as planned, the bid would propel the company even further ahead in the race to fill the void left by the US Space Shuttle program which ended in July last year. Otherwise, it would be a setback for SpaceX, one of several firms working to build and launch a spacecraft that could tote astronauts to the ISS by 2015.
“The attention given to this flight creates a set of high expectations and it’s still a test flight but the consequences of failure would be very serious,” said John Logsdon, space policy expert at George Washington University. “NASA is putting a big bet on this succeeding.”
The company has so far received $381 million from NASA as part of a multi-year $1.6-billion contract to expand the capability to carry cargo to and from the ISS.
NASA has also made a similar deal with a second company, Orbital Sciences, though it is yet to attempt its first cargo mission.
While, SpaceX became the first commercial enterprise to successfully launch its space capsule into low-Earth orbit and back for a safe ocean recovery in 2010, the compay has also been able to develop the Falcon 9 rocket launch vehicle at a third of the cost — $1.7 billion.
“They are playing with their own money and they have real incentives to hold down costs,” said Howard McCurdy, an author and space policy expert at American University in Washington. He said “SpaceX is in the lead but whether or not they are going to wind up in the lead at the end, we don’t know, that’s what makes it fascinating to watch”.
Source : http://zeenews.india.com/news/space/spacex-poised-to-dock-with-iss_775851.html
Australia seventh-worst polluter on Earth
May 16th
MELBOURNE: Australia has been ranked as the seventh top polluter mainly due to carbon emissions, a report said.
Conservation group World Wildlife Fund (WWF) in its report said the spiralling global population and over-consumption are threatening the future health of the planet, ABC news reported.
WWF released this year’s Living Planet Report, which has estimated humans are using 50 per cent more resources than the planet can provide. If everyone lived like the average Australian, it would take 3.76 planets to support the world’s population, the report said.
Qatar ranked on the top followed by Kuwait, UAE, Denmark, the United States and Belgium. WWF Australia ecologist Martin Taylor said it’s a top 10 ranking the nation should be ashamed of.
The results of the survey were calculated by comparing renewable resources consumed against the Earth’s regenerative capacity. The demand on natural resources has become unsustainable and is putting “tremendous” pressure on the planet’s biodiversity, the WWF said.
The report found that high-income countries have an ecological footprint on average five times that of low-income ones. “If the rest of the world lived the way we did, we’d need four planets,” Taylor said adding “We’ve only got one I’m afraid so something has to give at some point.”
Carbon emissions are the top contributor to Australia’s footprint, which the report measures in “global hectares” – a measure of the productive land and water area required to support our consumption and pollution levels.
Expedition 31 Blasts Off!
May 15th
After a six-week delay, the crew of Expedition 31 successfully launched aboard a Soyuz TMA-04M rocket on Tuesday, May 15 at 0301 GMT (11:01 p.m. EDT May 14) from Russia’s historic Baikonur Cosmodrome, located in the steppes of Kazakhstan.
The rocket will deliver NASA astronaut Joe Acaba and Russian cosmonauts Gennady Padalka and Sergei Revin to the International Space Station. After a two-day journey, their Soyuz capsule will dock with the ISS at 11:38 p.m. CDT on Wednesday.
The crew was originally slated to launch on March 30, but problems with a pressure test forced a delay until a new Soyuz rocket could be brought into service. In the meantime ISS crew members Don Pettit, ESA astronaut Andre Kuipers and cosmonaut Oleg Kononenko have had the station to themselves since April 27.
The three new crew members will remain on Space Station until mid-September, serving as flight engineers under Expedition 31 commander Oleg Kononenko until July 1, when the current crew will depart and Padalka will assume command, marking the beginning of Expedition 32.
For more news on Expedition 31, visit NASA’s ISS website here. Also, you can follow NASA astronaut Joe Acaba on Twitter @AstroAcaba.
Source : http://www.universetoday.com/95174/expedition-31-blasts-off/
Nasa to put man on asteroid by 2020s
May 14th
Astronauts Being Trained For Mission To Look For Minerals, Get Info On How To Destroy It
WASHINGTON: Nasa is reportedly training a team of astronauts for a mission to land on an asteroid by the end of the next decade.
The US space agency is training the astronauts to land on an asteroid to explore its surface, search for minerals and even learn the skills they may need to destroy it should one pose a threat to the Earth, ‘The Daily Telegraph’ reported.
Nasa plans to send the team to make contact with an asteroid up to three million miles away by the late 2020s; it would take them far beyond the current limit of the Moon, which is 239,000 miles from Earth.
Travelling at around 50,000 miles per hour around the Sun with almost non-existent gravity due to their small size, landing safely on these space rocks will present a significant challenge.
But, Major Tim Peake, a British astronaut with the European Space Agency, who is also being trained for the asteroid mission, said: “With the technology we have available and are developing today, an asteroid mission of up to a year is definitely achievable .” He added: “Asteroids are interesting on a number of different levels. Nasa is focused on the science you can achieve as asteroids are essentially a historical record of billions of years of universe where we can take samples from.
“These objects are also coming extremely close to Earth all the time, but we rarely hear about it. With enough warning we would probably send a robotic mission to deflect an asteroid, but if something is spotted late… we may have to look at manned missions to deflect it.
“That is when the skills we are learning about how to work on an asteroid could be useful.”
In fact, Nasa hopes to launch an unmanned spacecraft that will use a robotic arm to collect samples from an asteroid by 2016 before sending a manned mission by the late 2020s. A manned mission will aim to rendezvous with an asteroid up to three million miles from the Earth, taking around a year to make the entire round trip.
The astronauts could stay on the asteroid for up to 30 days. According to Nasa officials, such missions to asteroids could help test technology for future human missions to other planets including Mars. Nasa hopes that such missions will provide new scientific information about the early universe while also providing valuable information for ways of defending Earth from collisions with asteroids.
Mars Discovery: Giant Dunes Moving Around
May 11th
The Martian winter is over, and scientists are scouring the planet from ground and sky.
The latest findings? Like a giant sand box, the Red Planet’s massive sculpted sand dunes are often moving around.
Long thought to be ancient artifacts of a more windy and seismic past, dunes at the Nili Paterna crater and beyond appear static from Earth. But NASA’s Mars Reconnaissance Orbiter turned its HiRise high-resolution camera on the dunes for a period of 105 days, and found the Martian mounds were moving at a pace very similar to the dune fields of Antarctica here at home.
The Mars rover Opportunity is also on the move in the new spring, headed north on the planet to study dust and bedrock.
The new data will help researchers in a better global understanding of the Martian surface and development of future robotic and human missions to our red neighbor. Maybe a sand worm hunt. Or a spice harvest?
Himalayan forests at greater risk from climate change: Govt
May 10th
NEW DELHI: Climate change will be an additional stress on Indian forests, especially in upper Himalayan stretches, which are already subjected to multiple challenges including over-extraction, livestock grazing and human impact, a government report said here on Wednesday.
India’s second National Communication to the UN Framework Convention on Climate Change, released by environment minister Jayanthi Natarajan said that the assessment of climate impacts showed that at the national level, 45 per cent of forested grids are likely to undergo changes. In the report, a digital forest map of the country was used to determine spatial location of all the forested areas.
This map was based on a high-resolution mapping, wherein the entire area of India was divided into over 165,000 grids. Out of these, 35,899 grids were marked as forested grids – along with the forest density and forest types. Vulnerability assessment showed that sensitive forested grids are spread across India. “However, their concentration is higher in the upper Himalayan stretches, parts of Central India, northern Western Ghats and Eastern Ghats,” said the MoEF report towards fulfillment of reporting obligation under the convention.
