We Found The Perfect Spot To Land Our Moon Rover

When Dead Stars Collide!

Gravity has been making waves - literally.  Earlier this month, the Nobel Prize in Physics was awarded for the first direct detection of gravitational waves two years ago. But astronomers just announced another huge advance in the field of gravitational waves - for the first time, we’ve observed light and gravitational waves from the same source.

There was a pair of orbiting neutron stars in a galaxy (called NGC 4993). Neutron stars are the crushed leftover cores of massive stars (stars more than 8 times the mass of our sun) that long ago exploded as supernovas. There are many such pairs of binaries in this galaxy, and in all the galaxies we can see, but something special was about to happen to this particular pair.

Each time these neutron stars orbited, they would lose a teeny bit of gravitational energy to gravitational waves. Gravitational waves are disturbances in space-time - the very fabric of the universe - that travel at the speed of light. The waves are emitted by any mass that is changing speed or direction, like this pair of orbiting neutron stars. However, the gravitational waves are very faint unless the neutron stars are very close and orbiting around each other very fast.

As luck would have it, the teeny energy loss caused the two neutron stars to get a teeny bit closer to each other and orbit a teeny bit faster.  After hundreds of millions of years, all those teeny bits added up, and the neutron stars were *very* close. So close that … BOOM! … they collided. And we witnessed it on Earth on August 17, 2017.  

Credit: National Science Foundation/LIGO/Sonoma State University/A. Simonnet

A couple of very cool things happened in that collision - and we expect they happen in all such neutron star collisions. Just before the neutron stars collided, the gravitational waves were strong enough and at just the right frequency that the National Science Foundation (NSF)’s Laser Interferometer Gravitational-Wave Observatory (LIGO) and European Gravitational Observatory’s Virgo could detect them. Just after the collision, those waves quickly faded out because there are no longer two things orbiting around each other!

LIGO is a ground-based detector waiting for gravitational waves to pass through its facilities on Earth. When it is active, it can detect them from almost anywhere in space.

The other thing that happened was what we call a gamma-ray burst. When they get very close, the neutron stars break apart and create a spectacular, but short, explosion. For a couple of seconds, our Fermi Gamma-ray Telescope saw gamma-rays from that explosion. Fermi’s Gamma-ray Burst Monitor is one of our eyes on the sky, looking out for such bursts of gamma-rays that scientists want to catch as soon as they’re happening.

And those gamma-rays came just 1.7 seconds after the gravitational wave signal. The galaxy this occurred in is 130 million light-years away, so the light and gravitational waves were traveling for 130 million years before we detected them.

After that initial burst of gamma-rays, the debris from the explosion continued to glow, fading as it expanded outward. Our Swift, Hubble, Chandra and Spitzer telescopes, along with a number of ground-based observers, were poised to look at this afterglow from the explosion in ultraviolet, optical, X-ray and infrared light. Such coordination between satellites is something that we’ve been doing with our international partners for decades, so we catch events like this one as quickly as possible and in as many wavelengths as possible.

Astronomers have thought that neutron star mergers were the cause of one type of gamma-ray burst - a short gamma-ray burst, like the one they observed on August 17. It wasn’t until we could combine the data from our satellites with the information from LIGO/Virgo that we could confirm this directly.

This event begins a new chapter in astronomy. For centuries, light was the only way we could learn about our universe. Now, we’ve opened up a whole new window into the study of neutron stars and black holes. This means we can see things we could not detect before.

The first LIGO detection was of a pair of merging black holes. Mergers like that may be happening as often as once a month across the universe, but they do not produce much light because there’s little to nothing left around the black hole to emit light. In that case, gravitational waves were the only way to detect the merger.

Image Credit: LIGO/Caltech/MIT/Sonoma State (Aurore Simonnet)

The neutron star merger, though, has plenty of material to emit light. By combining different kinds of light with gravitational waves, we are learning how matter behaves in the most extreme environments. We are learning more about how the gravitational wave information fits with what we already know from light - and in the process we’re solving some long-standing mysteries!

Want to know more? Get more information HERE.

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Our universe is FULL of strange and surprising things.

And luckily, our Hubble Space Telescope is there to be our window to the unimaginable! Hubble recently ran into an issue with its payload computer which controls and coordinates science instruments onboard the spacecraft. On July 16, teams successfully switched to backup hardware to compensate for the problem! A day later, the telescope resumed normal science operations. To celebrate, we’re taking you back to 2016 when our dear Hubble captured perhaps one of the most intriguing objects in our Milky Way galaxy: a massive star trapped inside a bubble! The star inside this Bubble Nebula burns a million times brighter than our Sun and produces powerful gaseous outflows that howl at more than four million miles per hour. Based on the rate the star is expending energy, scientists estimate in 10 to 20 million years it will explode as a supernova. And the bubble will succumb to a common fate: It’ll pop.

Is there any chance that something could go wrong?

I've been very curious about the basis on which the landing site is decided! I read that it will land in the Jerezo crater, so is there a particular reason behind choosing that place for the landing?

"I used to measure the heavens; now I shall measure the shadows of the earth. Although my soul was from heaven, the shadow of my body lies here."

-Johannes Kepler-

Will the robot be able to send vedio footage?

See the Universe in a New Way with the Webb Space Telescope's First Images

Are you ready to see unprecedented, detailed views of the universe from the James Webb Space Telescope, the largest and most powerful space observatory ever made? Scroll down to see the first full-color images and data from Webb. Unfold the universe with us. ✨

Carina Nebula

This landscape of “mountains” and “valleys” speckled with glittering stars, called the Cosmic Cliffs, is the edge of the star-birthing Carina Nebula. Usually, the early phases of star formation are difficult to capture, but Webb can peer through cosmic dust—thanks to its extreme sensitivity, spatial resolution, and imaging capability. Protostellar jets clearly shoot out from some of these young stars in this new image.

Southern Ring Nebula

The Southern Ring Nebula is a planetary nebula: it’s an expanding cloud of gas and dust surrounding a dying star. In this new image, the nebula’s second, dimmer star is brought into full view, as well as the gas and dust it’s throwing out around it. (The brighter star is in its own stage of stellar evolution and will probably eject its own planetary nebula in the future.) These kinds of details will help us better understand how stars evolve and transform their environments. Finally, you might notice points of light in the background. Those aren’t stars—they’re distant galaxies.

Stephan’s Quintet

Stephan’s Quintet, a visual grouping of five galaxies near each other, was discovered in 1877 and is best known for being prominently featured in the holiday classic, “It’s a Wonderful Life.” This new image brings the galaxy group from the silver screen to your screen in an enormous mosaic that is Webb’s largest image to date. The mosaic covers about one-fifth of the Moon’s diameter; it contains over 150 million pixels and is constructed from almost 1,000 separate image files. Never-before-seen details are on display: sparkling clusters of millions of young stars, fresh star births, sweeping tails of gas, dust and stars, and huge shock waves paint a dramatic picture of galactic interactions.

WASP-96 b

WASP-96 b is a giant, mostly gas planet outside our solar system, discovered in 2014. Webb’s Near-Infrared Imager and Slitless Spectrograph (NIRISS) measured light from the WASP-96 system as the planet moved across the star. The light curve confirmed previous observations, but the transmission spectrum revealed new properties of the planet: an unambiguous signature of water, indications of haze, and evidence of clouds in the atmosphere. This discovery marks a giant leap forward in the quest to find potentially habitable planets beyond Earth.

Webb's First Deep Field

This image of galaxy cluster SMACS 0723, known as Webb’s First Deep Field, looks 4.6 billion years into the past. Looking at infrared wavelengths beyond Hubble’s deepest fields, Webb’s sharp near-infrared view reveals thousands of galaxies—including the faintest objects ever observed in the infrared—in the most detailed view of the early universe to date. We can now see tiny, faint structures we’ve never seen before, like star clusters and diffuse features and soon, we’ll begin to learn more about the galaxies’ masses, ages, histories, and compositions.

These images and data are just the beginning of what the observatory will find. It will study every phase in the history of our Universe, ranging from the first luminous glows after the Big Bang, to the formation of solar systems capable of supporting life on planets like Earth, to the evolution of our own Solar System.

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Credits: NASA, ESA, CSA, and STScI

reiterate the science they hate...

Roman’s Heat-Vision Eyes Are Complete!

Our Nancy Grace Roman Space Telescope team recently flight-certified all 24 of the detectors the mission needs. When Roman launches in the mid-2020s, the detectors will convert starlight into electrical signals, which will then be decoded into 300-megapixel images of huge patches of the sky. These images will help astronomers explore all kinds of things, from rogue planets and black holes to dark matter and dark energy.

Eighteen of the detectors will be used in Roman’s camera, while another six will be reserved as backups. Each detector has 16 million tiny pixels, so Roman’s images will be super sharp, like Hubble’s.

The image above shows one of Roman’s detectors compared to an entire cell phone camera, which looks tiny by comparison. The best modern cell phone cameras can provide around 12-megapixel images. Since Roman will have 18 detectors that have 16 million pixels each, the mission will capture 300-megapixel panoramas of space.

The combination of such crisp resolution and Roman’s huge view has never been possible on a space-based telescope before and will make the Nancy Grace Roman Space Telescope a powerful tool in the future.

Learn more about the Roman Space Telescope!

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