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Ancient Relativity Experiment Helps Measure a White Dwarf's Mass. Great balls of fire!

Ancient Relativity Experiment Helps Measure a White Dwarf's Mass

NASA's Hubble Space Telescope has detected superhot blobs of gas, each twice as massive as the planet Mars, being ejected near a dying star. The plasma balls are zooming so fast through space it would take only 30 minutes for them to travel from Earth to the moon. This stellar "cannon fire" has continued once every 8.5 years for at least the past 400 years, astronomers estimate. The fireballs present a puzzle to astronomers, because the ejected material could not have been shot out by the host star, called V Hydrae. The star is a bloated red giant, residing 1,200 light-years away, which has probably shed at least half of its mass into space during its death throes.

This four-panel graphic illustrates how the binary-star system V Hydrae is launching balls of plasma into space. Credits: NASA, ESA, and A. Mars Had Way More Water on its Surface Than We Thought - Universe Today. Mars has an extensive network of ancient valleys that were likely carved out by water over geologic time periods.

Mars Had Way More Water on its Surface Than We Thought - Universe Today

Now a new study suggests that Mars had much more water than previously thought, and the key behind calculating that amount of water is in the valleys themselves. The issue of exactly how much liquid water Mars had on its surface has been a hotly debated topic. There’s ample evidence that there was liquid water there. Orbiters and rovers have provided most of that evidence. Sedimentary rock, hydrated minerals that only form in the presence of water, and the obvious valleys, lake basins, and deltas all show that Mars was once a world with large quantities liquid water. This false-color composite image was taken by the Mars rover Opportunity.

But to find out how much water there was in Mars’ past, we have to go beyond what we can see with our orbiters and rovers and construct models. It’s clear that at some point in the past, Mars had liquid water. By Evan Gough. Einstein was right (again)! Astronomers watch as a star’s gravity bends light from another star. For only the second time in history, astronomers watched as the gravity of a nearby star bent the light from a more distant one, changing its apparent position in the sky.

Einstein was right (again)! Astronomers watch as a star’s gravity bends light from another star

This is pretty dang remarkable*, especially since the first time it was done was in 1919, and the star doing the gravitational bending that time was the Sun. That event, nearly a century ago, was during a total solar eclipse (the Sun, you may note, is pretty bright, making it hard to see nearby stars unless it’s eclipsed by the Moon) and was correctly hailed as the first experimental confirmation of Einstein’s Theory of Relativity. This more recent observation also capitalized on relativity, and did even more than that: It solved a long-standing issue about the physical properties of dead stars. Two New Satellites for Jupiter. Just a mile across, a pair of moonlets found orbiting Jupiter bring the planet's total satellite count to 69.

Two New Satellites for Jupiter

The advent of monster telescopes equipped with super-sensitive, wide-field detectors has been a boon for astronomical discoveries, among them a bevy of tiny moonlets around the outer planets. For example, observations made from 2000 to 2003 yielded 46 moons around Jupiter — more than two-thirds of the planet's total! Now astronomer Scott Sheppard (Carnegie Institution for Science) has added two more to the planet's extended family, bringing the total of known moons to 69. The announcements for S/2016 J 1 and S/2017 J 1 ("S" for satellite, "J" for Jupiter) came via Minor Planet Electronic Circulars issued on June 2nd and June 5th, respectively. When the stars align...well, one star with a hundred billion stars. Coincidences happen.

When the stars align...well, one star with a hundred billion stars.

Even in space. Or, at least, when we look into space from Earth. The sky is big, and you can only see a few thousand stars by eye, so honestly without optical aid you don’t see many that are super close together. But part of the main function of a telescope is to gather light, collecting it like rain in a bucket. Potential “Failed Supernova” Black Hole Discovered. Astronomers may just have watched a star collapse directly into a black hole — minus the supernova.

Potential “Failed Supernova” Black Hole Discovered

The failed supernova could help us understand how stars die. This pair of Hubble Space Telescope photos shows the massive star before and after it vanished, presumably by imploding to form a black hole. The left image shows the 25-solar-mass star as it appeared in 2007. But then it seemed to vanish, as seen in the right panel image from 2015. Juno: Surprises in First Science Results. From its dynamic atmosphere to its hidden depths, Juno reveals Jupiter as never before.

Juno: Surprises in First Science Results

An artist's conception of Juno in orbit around Jupiter. NASA Forget what you thought you knew about Jupiter. The first science results are in from NASA's Juno spacecraft, currently in orbit around Jove. The findings were published in this week's Science and Geophysical Research Letters today, along with a salvo of press releases. For starters, there was this eye-popping, never-before-seen sequence of Jupiter's aurorae, captured by Juno's Ultraviolet Spectrograph. Juno's orbit takes it around Jupiter once every 53 days, from a perijove 2,500 miles (4,000 km) above the Jovian cloud tops, to a five million mile (8 million km) apojove out past the orbit of Callisto.

Comparing Gas Giants It has been a thrilling ride, as Juno scans Jupiter in detail from pole-to-pole once every pass in a whirlwind six hour science phase. A swirling white spot captured by Juno on February 2nd. Juno is Ready to Tell Us What it Found at Jupiter - Universe Today. Even a casual observer can see how complex Jupiter might be.

Juno is Ready to Tell Us What it Found at Jupiter - Universe Today

Its Great Red Spot is one of the most iconic objects in our Solar System. The Great Red Spot, which is a continuous storm 2 or 3 times as large as Earth, along with Jupiter’s easily-seen storm cloud belts, are visual clues that Jupiter is a complex place. We’ve been observing the Great Red Spot for almost 200 years, so we’ve known for a long time that something special is happening at Jupiter. We knew Jupiter was weird. Now we're finding out HOW weird. If there’s one thing that shouldn’t surprise astronomers, it’s being surprised.

We knew Jupiter was weird. Now we're finding out HOW weird.

The trend is pretty clear: Every single time we look at the Universe in a new way —bigger telescopes, different wavelengths (colors) of light, space probes equipped with better detectors— we find stuff that is massively unexpected. Being surprised is in no way surprising. Yet here we are, surprised once again, standing in awe before the mightiest of the planets: Jupiter. The Juno spacecraft entered Jupiter orbit on July 4, 2016, and is on a looping 53-day trajectory that takes it 8 million kilometers out from the planet, then drops it screaming in to just 4200 kilometers above the planet’s north pole, traveling at a terrifying 200,000 kilometers per hour (125,000 mph). It swings down the planet, over the south pole, and is flung out once again. Seventh TRAPPIST-1 Planet Confirmed.

Astronomers have confirmed the existence of the seventh planet around the ultracool dwarf star TRAPPIST-1.

Seventh TRAPPIST-1 Planet Confirmed

Artist’s concept of what the sky might look like from one of the seven known terrestrial planets in the TRAPPIST-1 system. ESO / M. Kornmesser The modest M8 red dwarf star TRAPPIST-1 became famous after astronomers discovered seven small exoplanets in orbit around it. At the time the discoverers made the announcement in February, they couldn’t say much about the outermost world, labeled h: The astronomers had seen the planet — or, at least something they thought was a planet — pass in front of the star only once.

Saturn’s moons could reassemble after a cosmic smash-up. By Jeff Hecht. Jupiter surprises in first trove of data from NASA’s Juno mission – Spaceflight Now. The first months of observations of the solar system’s biggest planet from NASA’s Juno spacecraft have revealed huge swirling polar cyclones, previously-undetected structures and motions beneath Jupiter’s distinctive clouds, and the first evidence for what lies at the core of the gas giant, scientists said Thursday. There was plenty scientists did not know about the planet when the Juno spacecraft left Earth in 2011, and the probe has sought answers to questions about Jupiter’s interior, magnetic field, auroras and radiation belts, and used a visible light camera to capture the first direct views of the poles.

“The general theme of our discoveries is really how different Jupiter looks from what we expected,” said Scott Bolton, Juno’s principal investigator at the Southwest Research Institute in San Antonio. “Juno, in many ways, is looking inside Jupiter for the first time, close-up and personal.” “This was completely unexpected,” Bolton said. “There’s a theme here. The Star That Probably Doesn't Have an Alien Megastructure (But Maybe it Does) is Dimming Again - Universe Today.

In September of 2015, scientists announced that the star known as KIC 8462852 (aka. “Tabby’s Star” or “Boyajian’s Star”) was experiencing a strange dip in luminosity. At the time, astronomers indicated that this mysterious behavior could be the result of comets transiting in front of the star, but other (perhaps more hopeful) individuals claimed that it could also be the result of an alien megastructure.

This led to a flurry of studies and articles that sought to offer entirely natural explanations for what has been observed. Even SETI weighed in, indicating that they would begin searching for indications of radio signals coming this mysterious star. Astrophoto: Eight planets and a Moon, from east to west. Tunç Tezel is an astrophotographer, and one I’ve featured on the blog many times before. He has an eye for the unusual, something I appreciate very much.

He recently sent me a note that he had tried something a bit odd once again, and as usual I was amazed at his effort. ALMA Eyes Icy Ring around Young Planetary System – National Radio Astronomy Observatory. An international team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) has made the first complete millimeter-wavelength image of the ring of dusty debris surrounding the young star Fomalhaut. This remarkably well-defined band of rubble and gas is likely the result of exocomets smashing together near the outer edges of a planetary system 25 light-years from Earth. Earlier ALMA observations of Fomalhaut — taken in 2012 when the telescope was still under construction – revealed only about one half of the debris disk. Hi, Ho! 'Snow White' the Dwarf Planet Has Its Own Moon. Hubble Spots Moon Around Third Largest Dwarf Planet. Pioneer Probe's Plaque Returns to Earth as Crowdfunded Replica. Opportunity au bord d’une ravine - Ciel & Espace.

Cassini's 'Grand Finale' Portrait of Saturn. Titan's Northern Summer Clouds. Lava Waves Behind Jupiter Moon Io’s Temperature Changes? Observatories Combine to Crack Open the Crab Nebula. Three decades ago, astronomers spotted one of the brightest exploding stars in more than 400 years. The titanic supernova, called Supernova 1987A (SN 1987A), blazed with the power of 100 million suns for several months following its discovery on Feb. 23, 1987. Since that first sighting, SN 1987A has continued to fascinate astronomers with its spectacular light show. Saturn and Titan in the Milky Way. Emily Lakdawalla • May 8, 2017. Watch Comet Johnson Sprint Through Boötes. Stunning View of the Crab Nebula Just Got Five Times Better - Universe Today. Images of the Crab Nebula are always a treat because it has such intriguing and varied structure. Also, just knowing that this stellar explosion was witnessed and recorded by people on Earth more than 900 years ago (with the supernova visible to the naked eye for about two years) gives this nebula added fascination.

A new image just might be the biggest Crab Nebula treat ever, as five different observatories combined forces to create an incredibly detailed view, with stunning details of the nebula’s interior region. Titan's Northern Summer Clouds. Does Jupiter Have a Solid Core? - Universe Today. New Japanese mission will be going to the Moons of Mars - Universe Today. NASA probe finds Saturn ring gap emptier than predicted – Spaceflight Now. Cassini Traverses "Big Empty" on First Grand Finale Pass. Caught on camera: A Martian Opportunity hole-in-one. Calendrier cosmique de Carl Sagan. Rosetta Images Show Comet's Changing Surface Close Up - Universe Today. NASA, ISS partners quietly completing design of possible Moon-orbiting space station. China progresses toward first Orbital Logistics Mission, Space Station Module finishes Assembly – Spaceflight101. NASA's Plans to Explore Europa and Other "Ocean Worlds" - Universe Today.

7 Questions For 7 New Planets - Universe Today. Prediction: More gas-giants will be found orbiting Sun-like stars. Wonderful potentially habitable worlds around TRAPPIST-1. Time To Build A Venus Rover - Universe Today. Bad Astronomy - A Journey to Jupiter, without leaving Earth - Syfy Wire. Black Hole Feeds on Star for a Decade. Sending Mars Rovers on a 'Walkabout' Could Boost Their Science Output. Cassini offers best-ever view of Saturn’s rings – Spaceflight Now. Origin of Our Galaxy's Most Distant Stars. Amazing photos of tiny moons as Cassini orbits among the rings. What Was the Carrington Event? - Universe Today. When and How Did the Moon Form?

Two asteroid missions get nod from NASA – Spaceflight Now. Earth's Moon Formed in 'Moonlet' Mashup After Many Earth Impacts. New 'Enhanced Vision Telescope' Amplifies Cosmic Light for Skywatchers. Paired Stars in Cygnus En Route to Merger. Fifty Years of the Astronomical League Observing Programs. Hubble Spots Possible Exocomets in Nearby Star System - Universe Today. Bright Comet Prospects for 2017. Pandora Up Close. Saturn's hexagon recreated in the laboratory.

Showcasing the Benefits of NASA Technology Here on Earth - Universe Today. New Horizons. New Model Explains the Moon’s Weird Orbit. Bad Astronomy. The Universe's Galaxy Population Just Grew Tenfold - Universe Today. Universe Has 10 Times More Galaxies Than Researchers Thought. Impact! New Moon Craters Are Appearing Faster Than Thought. Solar System and Beyond. New Findings are Conclusive: Europa is crying out for exploration. Moon's Birth May Have Vaporized Most of Earth, Study Shows.

Astronomy Picture of the Day. Equatorial Maba Sky: From Big Dipper to the Southern Cross.