News & Current Affairs

July 21, 2009

Asia set for total solar eclipse

Asia set for total solar eclipse

Total solar eclipse photographed in Egypt, 2006 (Darren Baskill)

Stargazers will travel long distances to see the eclipse

Millions of people in Asia will see the longest total solar eclipse this century on Wednesday as swaths of India and China are plunged into darkness.

Scores of amateur stargazers and scientists will travel long distances for the eclipse, which will last for about five minutes.

The eclipse will first appear in the Gulf of Khambhat just north of Mumbai.

It will move east across India, Nepal, Burma, Bangladesh, Bhutan and China before hitting the Pacific.

The eclipse will cross some southern Japanese islands and will last be visible from land at Nikumaroro Island in the South Pacific nation of Kiribati.

Elsewhere, a partial eclipse will be visible across much of Asia.

The previous total eclipse, in August 2008, lasted two minutes and 27 seconds. This one will last six minutes and 39 seconds at its maximum point.

Alphonse Sterling, a Nasa astrophysicist who will be following the eclipse from China, scientists are hoping data from the eclipse will help explain solar flares and other structures of the sun and why they erupt.

“We’ll have to wait a few hundred years for another opportunity to observe a solar eclipse that lasts this long, so it’s a very special opportunity,” Shao Zhenyi, an astronomer at the Shanghai Astronomical Observatory in China told the Associated Press news agency.

Solar scientist Lucie Green, from University College London, is aboard an American cruise ship heading for that point near the Japanese island of Iwo Jima, where the axis of the Moon’s shadow will pass closest to Earth.

“The [Sun’s] corona has a temperature of 2 million degrees but we don’t know why it is so hot,” she said.

“What we are going to look for are waves in the corona. … The waves might be producing the energy that heats the corona. That would mean we understand another piece of the science of the Sun.”

The next total solar eclipse will occur on 11 July next year. It will be visible in a narrow corridor over the southern hemisphere, from the southern Pacific Ocean to Argentina.

TOTAL SOLAR ECLIPSE
Infographic (BBC)
In the area covered by the umbra (the darkest part of the shadow), a total eclipse is seen
In the region covered by the penumbra (where only some of the light source is obscured) a partial eclipse is seen

solar

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July 19, 2009

New images of Moon landing sites

Filed under: Latest — Tags: , , , , , , , , , , , , , , — expressyoureself @ 5:25 pm

New images of Moon landing sites

Apollo 14 (Nasa)

Apollo 14: Science instruments (circled left) and the lunar module descent stage (circled right) are connected by a footprint trail

A US spacecraft has captured images of Apollo landing sites on the Moon, revealing hardware and a trail of footprints left on the lunar surface.

The release of the images coincides with the 40th anniversary of the first manned mission to land on the Moon.

The descent stages from the lunar modules which carried astronauts to and from the Moon can clearly be seen.

The image of the Apollo 14 landing site shows scientific instruments and an astronaut footpath in the lunar dust.

It is the first time hardware left on the Moon by the Apollo missions has been seen from lunar orbit.

The pictures were taken by Nasa’s Lunar Reconnaissance Orbiter (LRO) spacecraft, which launched on 18 June.

Buzz Aldrin in front of lunar module

The Apollo 11 mission touched down on the Moon on 20 July 1969

The spacecraft is carrying three cameras on board: one low-resolution wide-angle camera and two high-resolution narrow-angle cameras mounted side-by-side.

These are known collectively as the Lunar Reconnaissance Orbiter Camera (LROC) instrument.

“The LROC team anxiously awaited each image,” said the instrument’s principal investigator Mark Robinson of Arizona State University.

“We were very interested in getting our first peek at the lunar module descent stages just for the thrill – and to see how well the cameras had come into focus. Indeed, the images are fantastic and so is the focus.”

Astronaut trail

The camera instrument was able to capture five of the six Apollo sites, with the remaining Apollo 12 site expected to be photographed in the coming weeks.

Future LROC images from these sites will have two to three times greater resolution.

Long shadows from a low sun angle make the locations of the lunar modules’ descent stages particularly evident.

Apollo 11 (Nasa)

A long shadow is cast by the Apollo 11 descent stage

The image of the Apollo 14 landing site had a particularly desirable lighting condition that revealed additional details.

The Apollo Lunar Surface Experiment Package, a set of scientific instruments placed by the astronauts at the landing site, is discernable, as are the faint trails between the module and instrument package left by the astronauts’ footprints.

The LRO satellite reached lunar orbit on 23 June and captured the Apollo sites between 11 and 15 July.

Though it had been expected that LRO would be able to resolve the remnants of the Apollo missions, these first images were taken before the spacecraft had reached its final mapping orbit.

“Not only do these images reveal the great accomplishments of Apollo, they also show us that lunar exploration continues,” said LRO project scientist Richard Vondrak of Nasa’s Goddard Space Flight Center in Greenbelt, US.

“They demonstrate how LRO will be used to identify the best destinations for the next journeys to the Moon.”

Although the pictures provide a reminder of past lunar exploration, LRO’s primary focus is on paving the way for the future.

Data returned by the mission will help Nasa identify safe landing sites for future explorers, locate potential resources, describe the Moon’s radiation environment and demonstrate new technologies.

November 4, 2008

Indian Moon probe pictures Earth

Earth (ISRO)

The terrain mapping camera will eventually help compile an atlas of the Moon

India’s Chandrayaan 1 spacecraft has sent back its first images.

The probe was launched on 22 October to embark on a two-year mission of exploration at the Moon.

Ground controllers in Bangalore instructed the probe to take pictures with its Terrain Mapping Camera as the spacecraft made a pass of the Earth.

Chandrayaan also fired its engines for three minutes to carry out an orbit raising manoeuvre which takes the probe closer to the lunar body.

That was the fourth manoeuvre of its type made by the spacecraft, extending its orbit to more than half the distance to the Moon.

Just one more like it is required to take Chandrayaan into the Moon’s vicinity, at a distance of 384,000km from Earth.

Keeping up

The first images, taken at an altitude of 9,000km, show the northern coast of Australia while others, snapped at a height of 70,000km, show Australia’s southern coast.

Earth (ISRO)

The camera takes black and white images at a resolution of 5m

The Terrain Mapping Camera is one of the eleven scientific instruments aboard Chandrayaan 1. The camera takes black and white pictures at a resolution of about 5m.

Once Chandrayaan reaches the Moon, it will slip into orbit to compile a 3D atlas of the lunar surface and map the distribution of elements and minerals.

The mission is regarded as a major step for India as it seeks to keep pace with other spacefaring nations in Asia.

The health of Chandrayaan 1 is being continuously monitored from the ISRO Telemetry, Tracking and Command Network (ISTRAC) in Bangalore with support from Indian Deep Space Network antennas at Byalalu.

The Indian Space Research Organisation (ISRO) – the country’s space agency – says that all systems have been performing well.

September 10, 2008

Sri Lanka jets bomb ‘rebel base’

Sri Lanka jets bomb ‘rebel base’

Sri Lanka Air Force MiG 27s (Photo from air force website)

Jets are said to have carried out raids deep inside rebel-held territory

Sri Lanka’s military says its jets have bombed a Tamil Tiger intelligence center in the north, a day after a rebel air raid on a military base.

Fighter aircraft pounded the rebel center in the northern region of Kilinochchi, the defense ministry said.

Reports from the area confirm an air raid, injuring at least two people. The rebels said civilian homes were hit.

The attack came as UN Secretary-General Ban Ki-moon expressed deep concern over the increased hostilities in Sri Lanka.

On Monday, the government issued a notice to foreign aid workers to leave the rebel-held areas in the north saying it could not guarantee their safety. On Tuesday, UN officials said they would relocate staff.

The government says that it is on track to defeat the rebels.

Displaced

Officials said the area where the latest military operation was carried out is deep inside rebel-held territory.

map

“Taking on offensive raids into the LTTE [Liberation Tigers of Tamil Eelam] backyard, Sri Lanka air force fighter jets made precision air sorties at the LTTE’s main intelligence command and control centre located in Kilinochchi,” the defense ministry said.

The region also houses several non-governmental organizations (NGOs) and aid agencies. The UN said one of its vehicles was slightly damaged.

The Tamil Tigers said the air force had bombed a civilian settlement near Kilinochchi town centre, destroying 12 homes.

“No one was hurt because people sought safety in the bunkers,” a statement said.

Photographs on their website showed buildings they said were civilian houses damaged or destroyed by the bombing.

Hospital officials told a pregnant woman had been injured in the bombing. She lost her baby after a stone hit her abdomen during the raid. A child also fainted.

Rubble of civilian homes the Tigers say were hit in the raid

Rubble of civilian homes the Tigers say were hit in the raid

There is growing concern for the fate of civilians in the north after the government ordered aid agencies to leave Tamil Tiger controlled territory.

The UN secretary general said the fighting had “grave humanitarian consequences for civilians”.

“He reminds all concerned of their responsibility to take active steps to ensure the safety and freedom of movement of civilians, allowing humanitarian organizations to do their work in safety, as well as to reach persons affected by the fighting who need humanitarian assistance,” a statement said.

Human rights group Amnesty International called for international monitors to be allowed into the north to oversee convoys of aid and other essential supplies.

There are about 70 UN national and international workers in areas of the north controlled by the Tamil Tigers, the UN says. Most are based in the town of Kilinochchi.

Aid agencies say there are nearly 160,000 people in the Tiger-controlled north who have been displaced by the fighting.

The International Red Cross (ICRC) – one of the most prominent international agencies in the north – said that its teams were committed to remain in both rebel and government-held areas.

Offensive

But an ICRC spokesman said that situation was being monitored and negotiations were currently underway with the government in Colombo.

UN camp for displaced people in Sri Lanka

The UN says the plight of civilians in the north is worsening

Correspondents say that part of the problem for some aid agencies in the north is that their staff cannot leave because they are Tamil locals and the rebels will not issue them with passes.

The military meanwhile says that its offensive – aimed at crushing the rebels and ending their fight for a separate state for the Tamil minority – is on course.

The ministry of defence said that it shot down a rebel plane on Tuesday in a major incident in which 12 soldiers and a policemen were killed during a Tamil Tiger attack on a base in the northern area of Vavuniya.

The Tigers said 10 of their suicide fighters were killed in the raid.

They said that the raid was backed by artillery and light aircraft dropping bombs and that a radar station was destroyed in extensive damage to the base.

The Tamil Tigers have been fighting for a separate state for the Tamil minority in the north and east of Sri Lanka for 25 years.

More than 70,000 people have died.

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