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Glittering Frisbee Galaxy: This image from Hubble’s shows a section of a spiral galaxy located about 50 million light-years from Earth. We tend to think of spiral galaxies as massive and roughly circular celestial bodies, so this glittering oval does not immediately appear to fit the visual bill. What’s going on? Imagine a spiral galaxy as a circular frisbee spinning gently in space. When we see it face on, our observations reveal a spectacular amount of detail and structure. However, the galaxy frisbee is very nearly edge-on with respect to Earth, giving it an appearance that is more oval than circular. The spiral arms, which curve out from the galaxy’s dense core, can just about be seen.

Although spiral galaxies might appear static with their picturesque shapes frozen in space, this is very far from the truth. The stars in these dramatic spiral configurations are constantly moving as they orbit around the galaxy’s core, with those on the inside making the orbit faster than those sitting further out. This makes the formation and continued existence of a spiral galaxy’s arms something of a cosmic puzzle, because the arms wrapped around the spinning core should become wound tighter and tighter as time goes on - but this is not what we see. This is known as the winding problem.

Image credit: ESA/Hubble & NASA

For more information on this image, visit: https://go.nasa.gov/2niODGL

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Faintest Galaxies Ever Seen Explain The ‘Missing Link’ In The Universe

“By warping space, the light from background objects gets magnified, revealing extraordinarily faint galaxies. The only problem? The cluster itself is closer and overwhelmingly luminous, making it impossible to tease out the distant signals. Until now. Thanks to a superior new technique devised by Rachael Livermore, light from the foreground cluster galaxies can be modeled and subtracted, revealing faint, distant galaxies never seen before.”

One of the biggest puzzles in science is exactly how the Universe became transparent to visible light. Neutral atoms – cosmic dust – blocks visible light, and yet before there were stars, that’s all we had. According to theory, it should be large numbers of small, faint, ultra-distant galaxies that made it transparent, but they’ve never been seen. However, thanks to the combined power of the Hubble Space Telescope, gravitational lensing and a new foreground light-removal technique, galaxies 100 times fainter thank the ones visible in the Hubble eXtreme Deep Field – the longest-exposure image ever – have now been revealed. These galaxies, seen in two Frontier Fields’ clusters so far, are the ‘missing link’ needed to explain reionization.

Come get the full, stunning story in visuals and no more than 200 words on today’s Mostly Mute Monday!

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How Lucky Was Hubble To Find The Most Distant Galaxy Ever?

“If you take the world’s most powerful space telescope, point it into the cosmic abyss for days, and collect all the light possible, you’ll see something fantastic. But you won’t see the Universe’s most distant galaxy.”

Arriving at our eyes after a journey of 13.4 billion years, the light from galaxy GN-z11 has been traveling towards us for 97% of the Universe’s present age. It’s detection and discovery, however, was a lot more complicated than simply opening up your telescope’s eyes and collecting enough light; a confluence of four separate things needed to happen all at once to make it possible. The telescope itself needed to be configured to detect light that had been shifted by the Universe’s expansion from ultraviolet to infrared. The volume of the Universe, from here to there, needed to be reionized enough to allow light to pass through it. Gravitational lensing needed to magnify the background galaxy to make it detectable. And spectroscopic confirmation was needed to ensure that the galaxy wasn’t an impostor.

After all that, we arrive at the undisputed record-holder for most distant galaxy in the Universe. Come get its full story today!

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ripples: Crab Nebula, photographed by Hubble, autumn 2005.

10 images in 558 nm (green) light, September-December 2005.

The Crab Nebula is a cloud of gas 11 light years across, created by the collapse and explosion of a giant star in 1054 AD (a Type II supernova). At the centre of the nebula is a neutron star, the Crab Pulsar, the incredibly dense remnant of the original star; 1.5 to 2 times the mass of the Sun, but only 30 km across. Intense solar wind from the pulsar creates visible ripples in the surrounding nebula.

From Proposal 10526. Some more gifs of the Crab Nebula seen by Hubble.

Image credit: NASA/ESA/STScI. Animation: AgeOfDestruction.

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The James Webb Space Telescope Will Truly Do What Hubble Only Dreamed Of

“By the same token, the James Webb Space Telescope will teach us an incredible amount about the Universe, including further details about how stars form, what the earliest stellar populations look like, will show us gas giants and rogue planets in unprecedented detail and will tell us what made up the Universe at any given time in the past. It will show us a whole slew of things that Hubble cannot, by virtue of it reaching to much longer wavelengths of light than Hubble could ever hope to see. And with its huge, large-aperture primary mirror, it will be able to collect more light in a single day than Hubble could in a week. The most exciting things, of course, will be the unexpected: the things we’ll discover that we don’t even know to look for yet.

But even if you don’t learn about any of the science that James Webb will bring to us, there’s one thing it will deliver that everyone can enjoy: the James Webb Space Telescope will show us how the Universe grew up.”

The Hubble Space Telescope, for all of its scientific findings and how it revolutionized our understanding of the Universe itself, touched us all in a way that no piece of knowledge could ever encapsulate. In perhaps the greatest find of all, Hubble answered a question that many of us have had on our minds every time we’ve gazed up at a night sky: what does the Universe actually look like? From its images of star-forming regions, stellar deaths, galaxies, gravitational lenses and the deep abyss of empty space, it’s awed us in a way no other observatory ever has. But James Webb is poised to do us one better, and show us something Hubble never could. It will show us how the Universe went from a state with no stars, no planets, and no galaxies to the Universe we know, recognize and inhabit today.

In short, the James Webb Space Telescope will show us how the Universe grew up. Come learn exactly what that means, and see if you aren’t awed by the possibility!

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How the Hubble Space Telescope changed the Universe

“And so this camera has taught us a lot about how stars die. But what it’s also told us about is how and where they’re born! You see, these nebulae don’t just dissipate after a few thousand years; they often spit out entire star systems worth of gas, and trigger the formation of new stars. One of the most spectacular pictures took place deep inside the Eagle Nebula.

And when Hubble imaged the pillars at the center of it, it was one of the most amazing things ever.”

Over its more than 25 year lifetime, the Hubble Space Telescope has shown us what the Universe truly looks like. It’s done so in a myriad of ways, from planets to stars – dying and forming – to galaxies to gravity’s effects to the deepest abysses of blackness of all. Nothing in space is the same as it was before humanity knew Hubble. Yet even the camera most responsible for our iconic images, WFPC2, isn’t the end of the story. That camera was removed in 2009, and in the 8 years since, we’ve deepened our views and our understanding even further. Even before the launch of the James Webb Space Telescope, our journey into the unknown Universe continues with Hubble in a way we never could have imagined when the observatory was first launched.

Come see for yourself in far more images than you’ve ever seen at once before!