In the early pre-dawn hours on December 19, 2013, with a rumble and a roar, a Soyuz rocket blazed through the clouds above the jungle-lined coast of French Guiana, ferrying ESA’s long-awaited Gaia spacecraft into orbit and beginning its mission to map the stars of the Milky Way. The fascinating time-lapse video above from ESA shows the Gaia spacecraft inside the clean room unfurling like a flower during its sunshield deployment test, the transfer of the Soyuz from the assembly building to the pad, and then its ultimate fiery liftoff.
That’s a lot going on in two minutes! But once nestled safely in its L2 orbit 1.5 million kilometers out, Gaia will have over five years to complete its work… read more here.
Credit: ESA–S. Corvaja, M. Pedoussaut, 2013. Source: ESA
Early this morning, at 09:12 UTC, the cloudy pre-dawn sky above the coastal town of Kourou, French Guiana was brilliantly sliced by the fiery exhaust of a Soyuz VS06, which ferried ESA’s “billion-star surveyor” Gaia into space to begin its five-year mission to map the Milky Way.
Ten minutes after launch, after separation of the first three stages, the Fregat upper stage ignited, successfully delivering Gaia into a temporary parking orbit at an altitude of 175 km (108 miles). A second firing of the Fregat 11 minutes later took Gaia into its transfer orbit, followed by separation from the upper stage 42 minutes after liftoff. 46 minutes later Gaia’s sunshield was deployed, and the spacecraft is now cruising towards its target orbit around L2, a gravitationally-stable point in space located 1.5 million km (932,000 miles) away in the “shadow” of the Earth.
The launch itself was really quite beautiful, due in no small part to the large puffy clouds over the launch site. Watch the video below:
A global space astrometry mission, Gaia will make the largest, most precise three-dimensional map of our galaxy by surveying more than a billion stars over a five-year period.
“Gaia promises to build on the legacy of ESA’s first star-mapping mission, Hipparcos, launched in 1989, to reveal the history of the galaxy in which we live,” says Jean-Jacques Dordain, ESA’s Director General.
Repeatedly scanning the sky, Gaia will observe each of the billion stars an average of 70 times each over the five years. (That’s 40 million observations every day!) It will measure the position and key physical properties of each star, including its brightness, temperature and chemical composition.
By taking advantage of the slight change in perspective that occurs as Gaia orbits the Sun during a year, it will measure the stars’ distances and, by watching them patiently over the whole mission, their motions across the sky.
The motions of the stars can be put into “rewind” to learn more about where they came from and how the Milky Way was assembled over billions of years from the merging of smaller galaxies, and into “fast forward” to learn more about its ultimate fate.
“Gaia represents a dream of astronomers throughout history, right back to the pioneering observations of the ancient Greek astronomer Hipparchus, who catalogued the relative positions of around a thousand stars with only naked-eye observations and simple geometry. Over 2,000 years later, Gaia will not only produce an unrivaled stellar census, but along the way has the potential to uncover new asteroids, planets and dying stars.”
– Alvaro Giménez, ESA’s Director of Science and Robotic Exploration
Of the one billion stars Gaia will observe, 99% have never had their distances measured accurately. The mission will also study 500,000 distant quasars, search for exoplanets and brown dwarfs, and will conduct tests of Einstein’s General Theory of Relativity.
“Along with tens of thousands of other celestial and planetary objects,” said ESA’s Gaia project scientist Timo Prusti, “this vast treasure trove will give us a new view of our cosmic neighbourhood and its history, allowing us to explore the fundamental properties of our Solar System and the Milky Way, and our place in the wider Universe.”
The Universe is expanding. Distant galaxies are moving away from us in all directions. It’s natural to wonder, is everything expanding? Is the Milky Way expanding? What about the Solar System, or even objects here on Earth. Are atoms expanding?
Nope. The only thing expanding is space itself. Imagine the Universe as loaf of raisin bread rising in the oven. As the bread bakes, it’s stretching in all directions – that’s space. But the raisins aren’t growing, they’re just getting carried away from each other as there’s more bread expanding between them.
Space is expanding from the Big Bang and the acceleration of dark energy. But the objects embedded in space, like planets, stars, and galaxies stay exactly the same size. As space expands, it carries galaxies away from each other. From our perspective, we see galaxies moving away in every direction. The further galaxies are, the faster they’re moving.
There are a few exceptions. The Andromeda Galaxy is actually moving towards the Milky Way, and will collide with us in about 4 billion years.In this case, the pull of gravity between the Milky Way and Andromeda is so strong that it overcomes the expansion of the Universe on a local level.
Within the Milky Way, gravity holds the stars together, and same with the Solar System. The nuclear force holding atoms together is stronger than this expansion at a local scale. Is this the way it will always be? Maybe. Maybe not.
A few decades ago, astronomers thought that the Universe was expanding because of momentum left over from the Big Bang. But with the discovery of dark energy in 1998, astronomers realized there was a new possibility for the future of the Universe. Perhaps this accelerating dark energy might be increasing over time.
In billions years from now, the expansive force might overcome the gravity that holds galaxies together. Eventually it would become so strong that star systems, planets and eventually matter itself could get torn apart.This is a future for the Universe known as the Big Rip. And if it’s true, then the space between stars, planets and even atoms will expand in the far future.
Is this going to happen? Astronomers don’t know. Their best observations so far can’t rule it out, or confirm it. And so, future observations and space missions will try to calculate the rate of dark energy’s expansion.
So no, matter on a local level isn’t expanding. The spaces between planets and stars isn’t growing. Only the distances between galaxies which aren’t gravitationally bound to each other is increasing. Because space itself is expanding.
This new panorama of the Milky Way by astrophotographer Miguel Claro is really amazing, and you definitely want to click on the image to have access to larger versions! This is an 18-image mosaic taken with a Canon 60Da, with 60 second exposures, and it rivals wide-field images taken by larger ground-based telescopes. The images, were, however, taken from the home of some of the darkest skies and largest telescopes in the world, near Roque de Los Muchahos, in La Palma, Canary Islands. Visible is the hazy band of white light that comes from unresolved stars and other material that lie within the galactic plane, contrasting with interesting shapes within the dark regions of the band, corresponding to areas where light from distant stars is blocked by interstellar dust.
Thanks to Miguel Claro for sharing his images with Universe Today!
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
Here’s a beautiful view of the Milky Way arching through the sky over the Isle of Wight, an island just off the south coast of England, known for having limited light pollution. This gorgeous image was taken by photographer Chad Powell. You can see more of Chad’s work on his website or his Facebook page.
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
Although the Zodiac is best known for astrology nonsense, it has a purpose in astronomy too. The constellations of the Zodiac define the plane of the ecliptic: the region where the Sun, Moon and planets appear to travel through the sky. What are the constellations of the Zodiac, and how do astronomers use them as way points?
We record Astronomy Cast as a live Google+ Hangout on Air every Monday at 12:00 pm Pacific / 3:00 pm Eastern. You can watch here on Universe Today or from the Astronomy Cast Google+ page.
Sunday’s Virtual Star Party felt like a reunion, with Mike Phillips, Gary Gonella, and Roy Salisbury supplying images and Scott Lewis co-hosting. We were joined by newcomer James McGee streaming a beautiful view of the Moon – when it wasn’t blocked by his apartment tower.
The Moon was just past full, so it commanded attention, but we still got a beautiful view of some fainter nebulae, galaxies and star clusters.
Astronomers: Mike Phillips, Gary Gonella, Roy Salisbury, James McGee
Hosts: Fraser Cain, Scott Lewis
Objects: The Moon, Pac Man Nebula, Eagle Nebula, Swan Nebula, Lagoon Nebula, Andromeda Galaxy, M15 globular cluster, Dumbbell Nebula, Veil Nebula and more.
We hold the Virtual Star Party every Sunday night when it gets dark on the West Coast of North America. You can watch it live on Universe Today, on Google+, or from the Universe Today YouTube Channel.
Need a little inspiration to go out and do some stargazing this weekend? Look no further than this gorgeous timelapse by Jack Fusco. There are awesome views of both sea and sky, the Milky Way, star trails, awesome cloud scenes and funky, directionally-challenged moving lights in the sky.
I’ve been working on a timelapse of the night sky over the New Jersey coastline,” Jack told us via email. “New Jersey definitely isn’t the best location for stargazing, but I think given the circumstances, many people will be surprised. I hope it inspires people to set some time aside to stargaze where they live even if they previously thought it wasn’t worth trying.”
Jack said he’s been working on this one for 10 months, and it’s definitely worth the hard work he’s put in.
Jack also gives a shout out to those affected by Hurricane Sandy last year. “A special thank you to all of those who have worked so hard to restore the homes of those lost during Sandy,” he writes on Vimeo. “Thank you to every volunteer that has spent time bringing the beauty back to our boardwalks and our beaches. The last year has been filled with heartbreak and devastation with much work still being done.”
Amateur astronomers from Illinois frequently venture out to Jim Edgar Panther Creek State Park, a 26-square mile conservation area of prairie and forest, famous for having the darkest skies in the state. But of course, lots of folks head out to the park to enjoy other things like the picturesque landscapes, the wildlife, and the solitude.
This past week my friend Ben Romang went to do some camping at Panther Creek, and with a borrowed camera, wanted to make his first attempt at photographing the night sky. He was hoping to nab some Perseid meteors, but instead was overwhelmed with the beauty of the expansive sky overhead. For his first try, I think he did a pretty good job of capturing the view, don’t you?
Ben used a Canon 7D, with an EF 24-70mm lens.
If you’d like to see these amazing dark skies for yourself, the perfect time would be during the annual Illinois Dark Sky Star Party, held every year by the local astronomy group in my area, the Sangamon Astronomical Society. It’s a great event, with a wonderful observing site, lots of room for camping, great food, interesting speakers (so claims their website — I’ve spoken there a few times!), and very friendly folks who are passionate about amateur astronomy. This year the Dark Skies Party is October 3-6, 2013. Find out more about the event here.
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.