Europe Launches Satellite to Map 1 Billion Stars

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Europe Launches Satellite to Map 1 Billion Stars
BERLIN December 19, 2013 (AP)
By FRANK JORDANS and DANICA COTO Associated Press



The European Space Agency launched its star-surveying satellite Gaia into space Thursday, hoping to produce the most accurate three-dimensional map of the Milky Way and to better understand the evolution of our galaxy.

The satellite was lifted into space from French Guiana at 6:12 a.m. (0912 GMT; 4:12 a.m. EST) aboard a Russian-made Soyuz rocket, the agency said.

Soon after the launch, Gaia unfurled its 10-meter (33-feet) circular sun shield — a crucial moment in the mission. The shield protects the spacecraft's sensitive instruments from the rays of the sun while simultaneously collecting solar energy to power the spacecraft.

"Everything was super smooth," said Paolo Ferri, head of mission operations at the Paris-based European Space Agency.

Gaia is now heading for a stable orbit around a point known as Lagrange 2 — some 1.5 million kilometers (930 million miles) away on the opposite side of the Earth from the sun. Once it gets there next month, the satellite's instruments will be switched on and it will follow what Ferri described as "a very peculiar pattern" designed to keep its back always turned to the sun.

Timo Prusti, ESA's project scientist, likened the mission's goal to the switch from two-dimensional movies to 3D. At the moment, he said scientists are working with a largely "flat" map of the galaxy.

"We want to have depth," he said.

Using its twin telescopes, Gaia will study the position, distance, movement, chemical composition and brightness of a billion stars in the galaxy, or roughly 1 percent of the Milky Way's 100 billion stars.

The data will help scientists determine the Milky Way's origin and evolution, according to Jos de Bruijne, deputy project scientist for the Gaia program.

"The prime importance of this mission is to do galactic archaeology," he said in a phone interview from French Guiana. "It will reveal the real history of our galaxy."

The project is the successor to ESA's Hipparcos satellite, which was launched in 1989 and measured the position of 100,000 stars in the Milky Way.

Gaia, which is named after an ancient Greek deity, will go far beyond that. Scientists have compared its measuring accuracy to measuring the diameter of a human hair from 1,000 kilometers (600 miles) away.

"There is still a lot that we don't understand about the Milky Way," said Andrew Fox, an astronomer with the Space Telescope Science Institute in Baltimore, Maryland. He is not involved in the project, but his position at the science center is funded by the European Space Agency.

ESA has dubbed Gaia the "ultimate discovery machine" because its sophisticated instruments will allow scientists to look for small wobbles in stars' movements that indicate the presence of nearby planets.

"Those are the stars that people are going to go out and look for planets around, and ultimately for signs of life," said Fox.

Equipped with dozens of cameras capable of piecing together 1,000-megapixel images, scientists also expect to find hundreds of thousands of previously undiscovered asteroids and comets inside our solar system.

Beyond that, scientists hope that Gaia can also be used to test a key part of Albert Einstein's General Theory of Relativity that predicts "dips" and "warps" in space caused by the gravity of stars and planets.

Carmen Jordi, an astronomer at the University of Barcelona who is involved in the mission, said the satellite's findings will become the main reference for scientists in the years to come.

"Almost all the fields of astrophysics will be affected," said Jordi.

The mission's scientific operations will begin in about 4 ½ months. The 740 million-euro ($1-billion) mission, which was delayed by about a month due to a technical problem with another satellite, has a planned lifetime of five years.

If Gaia is still operational after that, scientists say they might extend its mission for up to two years.


http://abcnews.go.com/Technology/wireStory/european-satellite-map-billion-stars-21273109

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Liftoff! European Spacecraft Launches to Map 1 Billion Stars
SPACE.com
By Elizabeth Howell, SPACE.com Contributor  8 hours ago



Artist representation of the Gaia spacecraft mapping the stars in the Milky Way galaxy.



A European probe roared into space Thursday (Dec. 19), kicking off an ambitious mission to map a billion Milky Way stars in high resolution.

The European Space Agency's Gaia spacecraft lifted off its pad at Europe's spaceport in Kourou, French Guiana at 4:12 a.m. EST (0912 GMT) Thursday, carried aloft by a Russian Soyuz-Fregat rocket. Gaia is on its way to a gravitationally stable point about 930,000 miles (1.5 million kilometers) from Earth, which it should reach in about three weeks.

Over the next five years, Gaia aims not only to pinpoint the locations of 1 billion stars in our Milky Way galaxy, but also to determine where these stars are moving, what they are made of and how luminous they are. These are all steps to help scientists better understand the history of the universe, ESA officials have said.

As a side benefit, Gaia's powerful twin telescopes will likely find thousands of new exoplanets, asteroids and other small, faint and hard-to-see objects.

?"Gaia will conduct the biggest cosmic census yet, charting the positions, motions and characteristics of a billion stars to create the most precise 3D map of our Milky Way," ESA officials said in a statement.



Artist's conception of the Gaia launch, showing the fairing jettison.


A long journey

Thursday's launch ended a long wait for the Gaia team, who saw the $1 billion (740 million euros) mission delayed from an initial 2011 launch due to telescope mirror issues, among other things.

But there is more waiting yet to come, as Gaia still has a lot of ground to cover before reaching its ultimate destination, a spot called the sun-Earth Lagrange Point 2 (L2). Lagrange points are regions in space where gravitational and orbital interactions allow spacecraft to essentially park in one spot.

And once at L2, Gaia will undergo a four-month commissioning period to make sure the spacecraft, its  telescopes and other gear are working properly.

Gaia also sports a sunshield, which has two purposes: To hold solar panels to generate electricity, and to be a barrier around Gaia's base against the heat of the sun. The spacecraft's instruments require a temperature of minus 166 degrees Fahrenheit (minus 110 degrees Celsius) to function. With the sunshield deployed, Gaia will stretch more than 33 feet (10 meters) across.


Mapping the sky

During science operations, Gaia will spin to get a view of the entire sky. Images will be stored using a single digital camera that has almost 1 billion pixels of resolution, making it the largest digital camera ever to fly in space.

Gaia is designed to be 100 times more accurate than Hipparcos, the last high-profile ESA star-mapping mission, which flew between 1989 and 1993. Hipparcos tracked down the locations of 100,000 stars precisely, and 1 million stars with less accuracy.

Gaia's name originally stood for Global Astrometric Interferometer for Astrophysics, but the interferometer was dropped early in the mission design because astronomers felt they could get a better view of fainter stars with an optical telescope. The name remained for project continuity.


http://news.yahoo.com/liftoff-european-spacecraft-launches-map-1-billion-stars-120821760.html

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Europe launches billion-dollar Milky Way telescope
AFP
By Richard INGHAM   5 hours ago



This handout picture released on August 8, 2013 by the European Space Agency (ESA) shows an artist impression of Gaia



Paris (AFP) - The European Space Agency on Thursday launched an advanced telescope designed to detect a billion stars and provide the most detailed map yet of the Milky Way and our place in it.

The Gaia telescope was successfully hoisted by a Soyuz-STB-Fregat rocket from ESA's space base in Kourou, French Guiana, the agency reported in a webcast.

The star-hunter separated from the last of the rocket's four stages 42 minutes after launch, and mission controllers said everything was fine.

The 740-million-euro ($1.02-billion) device, the most sophisticated space telescope ever built by Europe, aims at building an "astronomical census" of a billion stars, or around one percent of all the stars in the Milky Way.

By repeating the observations as many as 70 times throughout its mission, Gaia can help astronomers calculate the distance, speed, direction and motion of these stars and build a 3-D map of our section of the galaxy.

The stellar haul will be 50 times greater than the bounty provided by Hipparcos, a telescope of the early 1990s whose work provided a gold-standard reference guide still widely used by professional astronomers today.



Presentation of the Gaia space telescope, which aims to provide a 3D map of the Milky Way (AFP Photo/)


"Gaia is the culmination of nine years of intensive work which will enable exceptional advances in our understanding of the Universe, its history and laws," said Jean-Yves Le Gall, head of France National Centre of Space Studies (CNES), which is taking a lead role in the mission.

"We are at the dawn of revolutionising our understanding of the history of the Milky Way," said Stephane Israel, boss of Arianespace, which launched the satellite.

A Soviet-era workhorse of space with an excellent record of reliability, Soyuz is deployed at Kourou under a deal to widen Arianespace's options for the world's satellite launch market.

Gaia will also help in the search for planets beyond our Solar System -- as many as 50,000 so-called extrasolar planets could be spotted during the satellite's five-year life, astronomers hope.

It will do this by measuring the "wobble" in light that occurs when a planet passes in front of a star. The tug of its gravity causes a minute deflection in the stellar light reaching the telescope.



A picture released by the European Space Agency (ESA) and France's National Centre for Space Studies


Gaia will also observe the asteroid belt between Mars and Jupiter to help the search for any rocks that may one day threaten Earth, and keep a watch for distant exploding stars, called supernovae, which are rarely observed in real time.

The 2.03-tonne telescope "is so sensitive that it can measure the equivalent of the diameter of a hair at a distance of 1,000 kilometres", or 600 miles, CNES says on its website.

"If Hipparcos could measure the angle that corresponds to the height of an astronaut on the Moon, Gaia will be able to measure his thumbnail," according to ESA.

Gaia will start its star survey in May after taking up position at the so-called Lagrange point L2, located 1.5 million kilometres (937,000 miles) from the Earth, which offers year-round observation of the cosmos without the view being disturbed by the Sun, Earth or Moon.

To stay at L2, the spacecraft will have to perform tiny manoeuvres each month, scrutinised by a network of telescopes on Earth to ensure a hoped-for accuracy of 100 metres (yards).

ESA members have set up a network of 30 centres, manned by 450 people, to crunch the raw data, including a supercomputer at CNES's base in Toulouse, southwestern France, capable of carrying out six thousand billion operations a second.

Even so, it will take years to transform the million billion bytes of input into useable maps and catalogues.


http://news.yahoo.com/billion-dollar-39-discovery-machine-39-set-launch-021515712.html