Galaxy Evolution Explorer Retired

After 10 years of absolute success, after ten years of looking across 10 billion years of time and hundreds of millions of galaxies NASA has retired its Galaxy Evolution Explorer (GALEX) telescope. During its time in the skies GALEX achieved all of its main objectives and worked for far longer than its original time schedule. Some of the most poignant moments in its lifetime were the discovery of a massive comet-like tail behind a star called Mira, the catching of a black hole munching on a star, observing giant rings of new stars around old dead galaxies and independently confirming the nature of dark energy. Last year the telescope was loaned to the California Institute of Technology by NASA which then used it to study hundreds of thousands of galaxies around 5 billion light years away; this data will be made public in the coming year. The telescope will remain in orbit for another 65 years before falling to Earth and burning up on reentry.

Check out a slideshow of the most popular images taken by GALEX!

Can we just talk for a moment about these two precious people here?

Sometimes I just get hit by an overwhelming surge of emotion for these two because for me, their story will forever be one of the most heartbreaking love stories ever told.

At first she hates his world and his ways and him and all she wants is to leave, and he hates her for being too similar to and yet so different from Sam. But with everything they go through together, they develop this beautiful relationship whereby they trust each other implicitly, and considering that they are two people not apt to fully trust others, that’s amazing. And then he falls in love with her sexy, confident, no-nonsense exterior and the frailties she hides inside of herself, and she falls in love with the rude, sarcastic, alpha-male image he likes to perpetuate and the fears and the insecurities he does his best to hide from even himself. 

But they never get a chance. Not one single chance to even acknowledge that they love each other, let alone act on it or tell each other. They’re both torn a million different ways by a million different other factors - they go through so much together, they reach breaking point time and time again, but time and time again they come through it, together, and it takes my breath away how deep the trust between them really ran in the end. The dynamic between them is so complex - far more complex than I could ever summarise here or in any fanfiction, but that moment where Alex is standing there and Gene is on the floor, broken, and she says ‘I’m not leaving him’. That moment is one of the most powerful of the series and it breaks my heart. They deserved so much better than their fates - they deserved each other. 

And then when they finally did get the glimmer of a chance, when the possibility of an opportunity to be open with each other, to be together, came along… He sent her away. And she went. 

And that will never not kill me. 

A dying star is refusing to go quietly into the night, as seen in this combined infrared and ultraviolet view from NASA’s Spitzer Space Telescope and the Galaxy Evolution Explorer (GALEX), which NASA has lent to the California Institute of Technology in Pasadena. In death, the star’s dusty outer layers are unraveling into space, glowing from the intense ultraviolet radiation being pumped out by the hot stellar core.

This object, called the Helix nebula, lies 650 light-years away in the constellation of Aquarius. Also known by the catalog number NGC 7293, it is a typical example of a class of objects called planetary nebulae. Discovered in the 18th century, these cosmic works of art were erroneously named for their resemblance to gas-giant planets.

Planetary nebulae are actually the remains of stars that once looked a lot like our sun. These stars spend most of their lives turning hydrogen into helium in massive runaway nuclear fusion reactions in their cores. In fact, this process of fusion provides all the light and heat that we get from our sun. Our sun will blossom into a planetary nebula when it dies in about five billion years.

When the hydrogen fuel for the fusion reaction runs out, the star turns to helium for a fuel source, burning it into an even heavier mix of carbon, nitrogen and oxygen. Eventually, the helium will also be exhausted, and the star dies, puffing off its outer gaseous layers and leaving behind the tiny, hot, dense core, called a white dwarf. The white dwarf is about the size of Earth, but has a mass very close to that of the original star; in fact, a teaspoon of a white dwarf would weigh as much as a few elephants!

The intense ultraviolet radiation from the white dwarf heats up the expelled layers of gas, which shine brightly in the infrared. GALEX has picked out the ultraviolet light pouring out of this system, shown throughout the nebula in blue, while Spitzer has snagged the detailed infrared signature of the dust and gas in red, yellow and green. Where red Spitzer and blue GALEX data combine in the middle, the nebula appears pink. A portion of the extended field beyond the nebula, which was not observed by Spitzer, is from NASA’s all-sky Wide-field Infrared Survey Explorer (WISE). The white dwarf star itself is a tiny white pinprick right at the center of the nebula.

More information about Spitzer is online at http://spitzer.caltech.edu and http://www.nasa.gov/spitzer . More information about GALEX is at http://www.galex.caltech.edu .


more info on this nebula here