Changing Planet

Billion Star Sky Surveyor Launches

Europe’s Gaia Space Telescope promises to create the most accurate map of the Milky Way galaxy ever attempted. Credit: ESA/ATG medialab; background: ESO/S. Brunier

Astronomers plan on rewriting the star-charts with the latest space telescope, which aims at unlocking the secrets behind the birth and evolution of our home galaxy.

Europe’s new Milky Way Galaxy mapping-mission, called Gaia, is about to embark on a space mission that should create the most detailed three-dimensional star chart of the nearest billion stars. Each and every target star will have its position, distance, movement, and changes in brightness followed at least 70 times over a five year period. (See also “Mystery Deepens Over Where Sun Was Born“.)

The two-ton space telescope,  launched on Thursday on a Russian Soyuz rocket, headed into orbit from the European Space Agency’s spaceport in French Guiana.

Light from the cosmos will focus onto Gaia’s eye, a single digital camera equipped with a billion-pixel CCD chip-set, the largest and most sensitive light-detector ever flown in space.

With 100 individual mini-detectors working in concert, star positions will be measured with stunning precision, down to 10 micro arc-seconds of accuracy. “This is an astonishing step up in accuracy. To give an example, Gaia will measure the difference in position of one side of a human hair compared to the other side of it—in Paris, as viewed from London,” said mission scientist Mark Cropper, from the Mullard Space Science Laboratory in a statement.

Expectations are that Gaia will also be able to peer at extremely faint objects too—down to magnitude 20—about 400,000 times fainter than what the naked eye can see looking up at the night sky.

Astronomers hope that the flood of data returned will unlock some of the mysteries behind the origin and evolution of our Milky Way Galaxy and create a brand new catalog of tens of thousands of new and exotic objects, including supernovae, blazars, dwarf stars, exoplanets, and even asteroids in our own solar system.


Follow Andrew Fazekas, the Night Sky Guy, on Twitter and Facebook.

Andrew Fazekas, aka The Night Sky Guy, is a science writer, broadcaster, and lecturer who loves to share his passion for the wonders of the universe through all media. He is a regular contributor to National Geographic News and is the national cosmic correspondent for Canada’s Weather Network TV channel, space columnist for CBC Radio network, and a consultant for the Canadian Space Agency. As a member of the Royal Astronomical Society of Canada, Andrew has been observing the heavens from Montreal for over a quarter century and has never met a clear night sky he didn’t like.
  • Darren

    That’s awesome

  • dara

    is it just me or does this thing look exactly like a flying saucer?

  • stinker

    Here’s a novel idea: buy food for the homeless with the money that you are using to make a useless 3D map of the stars.

  • sami ullah


  • Eric

    Looking at the stars always fascinate me

  • Silviu

    Stinker… You can share your ideea with your government… See how it works…
    Merry Christmas!!!

  • kf

    Here’s a better idea Stinker. Cancel your internet and give that money and all the time you waste on the internet to help the homeless and feed the poor. It’s probably a much better use of your resources.

  • Rastaman

    @Stinker, Should guess you know the importance of the universe by now and its understanding as your on the national geographic channel and not mother teresa 24/7. ”Astronomers hope that the flood of data returned will unlock some of the mysteries behind the origin and evolution of our Milky Way Galaxy and create a brand new catalog of tens of thousands of new and exotic objects,” if those hopes are met, who knows, life on earth will be very very different as understanding of the bigger picture gets better. and maybe just maybe everybody will finnaly open their eyes, and see the importance of this.

  • MJM

    I’m pretty sure that’s actually a picture of the spaceship in Star Trek: The Motion Picture.

  • kmonsoor

    Use that money to explore our sea floors which we can readily gather resources from, and meet mass people’s necessity …

  • chuk

    Help the poor get off there butts and change there government that’s what u should be doing stinker. Let’s reach for the stars

  • Dwayne LaGrou

    I have heard of all the things listed except “Blazars”! Can anyone explain what those are exactly?
    Thank You & Happy Holidays To All

  • robert Whitford

    Of course I’m excited, about Space technology, and exploration, but for me a bit more than Half a Century in age, I’ve been waiting, for Universal peace, the end of Hunger and Human,as well as the Suffering of all beings, I think We should take care these issues first before, We get a map of the Other places, We intend on Conquering, and Messing up, imposing Our views upon. But it seems W’ere more about escaping Our mistakes then fixing them. That’s Human.

  • arup ghosh

    excelent picture and details about this is good.

  • Dale

    @ D L: A blazar is a very compact quasar, (quasi-stellar radio source), associated with a presumed super-massive black hole at the center of an active, giant elliptical galaxy. Blazars are among the most energetic phenomena in the universe and are an important topic in extragalactic astronomy

  • Martin Hunt

    These scientific advances are truly amazing and I believe any research and development that gets funding these days either from a private investor or government funding is inspiring for the next generation of budding scientists and astronomers. For all the cynics out there who think scientific funding could be better spent solving world hunger and desease, you would be amazed at how much time and money gets wasted on just trying to get food aid to starving countries, currupt diplomats and greedy governments who don’t want their people to become strong and healthy make sure this is always an up hill struggle….. Maybe I am cynical too but it takes lots of different colours to make this patch work quilt we call a world.

  • Sarah Arnold

    I have been talking to a women named Allison and she believes in the big bang. But,whoever is a christian on this blog,I hope you can soften sombodys Heart to believe in the true creator.Just so you people know I am only 11 years old,but I still share the gospel.

  • Sarah Arnold

    Stinker,maybe you should stop thinking about your self.and Dara I think it looks like a flying saucer,too.

  • Sarah Arnold

    Question-When did earth and space began?I am only asking unbeleivers.And DON’T TRY TO FIND ANY WRONG EVIDENCE!!!

  • KTL

    Humans use materials and tools to create. God could be using science and evolution as tools to create. The Bible and science may not be conflicting–only being judged as the same topic when actually they are different but connected.

  • thales

    que legal, ciência está evoluindo muito rápido!

  • Sarah Arnold

    Ktl,no that’s not right,God created us and other creation on his own.

  • Jamie Arnold

    I think we have aliens invading!!!

  • Ben

    Organized religion is a sham and a crutch for weak-minded people who need strength in numbers. It tells people to go out and stick their noses in other people’s business. I live by the golden rule: Treat others as you’d want them to treat you. The religious right wants to tell people how to live.

  • Nick

    Looks like a hat…

  • Sarah Arnold

    I agree Nick.

  • TASmith

    Stinker, the reason this project isn’t useless is because we’re effectively opening our eyes. For almost all of human history, we’ve flown about the sun with the lights out, oblivious to everything but the brightest planets and stars. But we’ve always been curious. The oldest myths all refer to gods drawn as constellations in the stars. This project matters because, with our eyes finally open, who knows what we’ll see? That’s why Hubble matters. That’s why this matters.

  • kaya

    Hi guys hope you visit my blog is about the universe i have alots of questions there please comment…

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