Milky Way Has Burping Black Hole Neighbor
X-ray: NASA/CXC/Univ of Texas/E.Schlegel et al; Optical: NASA/STScI
Using Chandra observations, astronomers have discovered one of the nearest supermassive black holes to Earth that is currently undergoing powerful outbursts. This image shows the galaxy M51 and its smaller component NGC 5195. In the close-up, a pair of arcs can be seen in the Chandra data and is evidence for outbursts from the supermassive black hole at the center of NGC 5195.
Space Stories 2015
Every year, Discovery News turns to our faithful readers to see which space stories excited you the most and 2015 has been yet another incredible year for astronomy, spaceflight, planetary science and solar system discovery. After pulling together the nominations by considering web traffic over the past 12 months,the selection was put up for a vote
across social media and the top 10 quickly became obvious -- with a very clear winner. Can you guess which stories made it into the top 10? Read on to find out.
(Want to compare this year's top 10 with last year? Read "Top 10 Space Stories of 2014: Readers' Choice
With NASA's Dawn mission arriving at Ceres and New Horizons flying past Pluto, 2015 will forever be known as the "Year of the Dwarf Planet." But Ceres will forever be known as the dwarf planet we visited
. In March, the mission, that had made the slow transit from massive asteroid Vesta,arrived in Ceres orbit
, revealing a fascinating, pock-marked surface. A puzzle quickly presented itself -- what the heck are those bright spots? Although Dawn is orbiting the tiny world closer than ever,these bright patches still perplex scientists
, highlighting just what a mysterious and fascinating place Ceres is.PHOTOS: Ceres Delights: Dawn's Latest Dwarf Planet Views
20th Century Fox
Sure, it's a movie, but it's a movie that starred Matt Damon and co-starred SCIENCE! Not only did "The Martian" become a box office success, it was a rare movie that pleased scientists and the general public alike. There were afew scientific missteps
, but overall, it was a science fiction movie that realized that scientific accuracy can drive a great story forward without having to unnecessarily stray into scientific fantasy.
The Martian: Science vs. Fiction
Tour 'The Martian' Movie Set... On Mars
While many of the headlines focus on its younger roving cousin, Curiosity, NASA's Mars Exploration Rover Opportunity is still exploring the Red Planet despite 10 years of dusty wear and tear. The veteran robothas even completed an extraterrestrial marathon this year
, proving thatyears of steady progress
, despiterecently suffering more "amnesia" problems
, can pay off. Be sure to keep an eye on this mission, it's not done with Mars quite yet.MORE: 10 Years On Mars: Opportunity’s First Sols
The NASA/ESA Hubble Space Telescope is nothing short of a scientific and cultural phenomenon. Since 1990, the powerful space telescope has been pushing the boundaries of astronomical breakthroughs, refining our understanding of our place in the cosmos. And this year it celebrated its
quarter of a century
in space -- an incredible feat. As we look forward to the launch of NASA's James Webb Space Telescope (scheduled for 2018), we can only hope that Hubble's successor will have the longevity of the world's most famous space telescope.
Hubble at 25: The Space Telescope by the Numbers
Hubble at 25: What's Next for the Space Telescope?
Hubble at 25: Space Telescope's Top Science Discoveries
Hubble at 25: Brief History of the Hubble Space Telescope
continues to wow the world with incredible images and science from the slopes of Mount Sharp in the center of Gale Crater. The robotic geologist has not only revealed the stunning array of surface features the region has to offer, but it has also discovered potential for past habitable environments andan abundance of evidence for past liquid water flowing on Mars' surface
. It is a mission of epic proportions and has been a Reader's Choice favorite since it landed on the Red Planet in 2012 -- we can't wait to see what adventures Curiosity has in store for us in 2016.PHOTOS: Curiosity Plays in Sandy Martian Dunes
After a decade of orbiting Saturn, NASA's Cassini mission has startedits farewell tour
. Having most recently carried out its final flyby of enigmatic moon Enceladus, the spacecraft will begin maneuvers in 2016 that will ultimately see the mission fly through the planet's ring plane. Then, the spacecraftwill conclude its "Grand Finale"
, burning up in Saturn's atmosphere. 2015 has been a huge year for Cassini, revealing more incredible science about Saturn's system of moons, rings and dynamic atmosphere and we look forward to more science and beautiful images like this onebefore mission end
.MORE: Cassini's Final Flyby of Ice Moon Enceladus
This story rapidly became 2015's viral story of the year because...
Actually, it'sprobably a cloud of comets
, but the mere hint ofa possible alien megastructure orbiting a star some 1,500 light-years away
was enough to throw the internet into a spin. But the best thing about this story is that NASA's Kepler space telescope was thrown into the limelight and the stunning science of exoplanet detection became an international talking point. Since the original detection of the weird transit signal discovered by citizen scientists of the Planet Hunters project, the SETI Institute has turned its powerful Allen Telescope Array at Tabby's Starto find no transmitting aliens
. Still, it doesn't mean it's
aliens, it just means there are far more likely explanations.MORE: Has Kepler Discovered an Alien Megastructure?
Ahhh, water on Mars. Yes, we already know that there's water ICE on Mars, but this time it's different. Well, it MIGHT be different. Way back in 2011, some strange seasonal channels were spotted by NASA's Mars Reconnaissance Orbiter on Martian slopes. Though they looked like channels created by flows of liquid water, scientists urged caution -- Mars' atmosphere is so cold and thin, only short-lived water ice should exist, right? But after orbital analysis this year, the chemical residue of these channels was analyzed, revealing that these channels may well be causedby gushing liquid water
. However, this water isn't your fresh mountain spring variety --it's highly toxic water
laced with perchlorates,if it is indeed liquid water...
MORE: So Liquid Water Flows on Mars -- Now What?
Commercial access to space has been ramping-up in recent years and 2015 has seen some of the biggest advances.Orbital Sciences has bounced back
after itsAntares rocket explosion
in 2014 and, though suffering its own huge setback witha Falcon 9 rocket explosion
in June, SpaceX returned with adramatic launch and 1st stage rocket return this month
. Add these historic advances toBlue Origins own suborbital rocket return
and we have seen 12 exciting months of commercial spaceflight successes not only to resupply the space station, but also to launch satellites and refine rocket technology. Next stop Mars?Who knows
.MORE: Lesson of SpaceX Rocket Landing: Try, Try, Try Again
It's been a long wait, but in July, NASA's New Horizons mission flew through the Pluto-Charon system for itshistoric and long awaited flyby
. The spacecraft, which took nearly a decade to reach the outer solar system, is now blasting through the Kuiper Belt and mission scientists aresteering it toward a Kuiper Belt object (KBO)
for another flyby in 2019. But its Pluto flyby was just the beginning -- the spacecraft recorded so much data that it continues to beam back detailed information about the dwarf planet,its weirdly dynamic surface
, it'scrazy assortment of moons
and someperplexing mysteries along the way
. This has been a historic year; we're finally seeing Pluto up-close and in high-definition for the first time since it was discovered by American astronomer Clyde Tombaugh in 1930.PHOTOS: Dive Onto Pluto's High-Resolution Landscape
A supermassive black hole at the center of a neighbor galaxy apparently “burped” after swallowing up nearby matter, a phenomenon that may have been instrumental in shaping the early universe, new research shows.
Scientists using NASA’s Chandra X-ray telescope found two streams of X-ray emissions near the heart of NGC 5195, a small galaxy located about 27 million light-years away. The galaxy is in the process of merging with another galaxy, NGC 5194, a large spiral also known as “The Whirlpool.”
A second set of observations from the Kitt Peak National Observatory’s 0.9-meter optical telescope revealed a thin region of relatively cool hydrogen gas just beyond the outer arc of X-rays.
Scientists believe hot gas, which generated the X-ray emissions, plunged into the cooler regions, like a snowplow.
“This is the best example of snow-plowed material I’ve ever seen. This is clearly a way of ejecting gas from a galaxy,” astronomer Eric Schlegel, with the University of Texas, San Antonio, said at the American Astronomical Society meeting in Kissimmee, Florida, on Tuesday.
“We would expect this would happen a lot more often in the early universe. You get galaxies at a higher density, they’re going to collide more often and you’re going to get this kind of effect,” he added.
The research indicates that a black hole not only consumes matter that strays into the region of space warped by its gravity, but that the black hole can eject material as well.
Schlegel said it’s possible the arcs of X-rays stem from material that was gravitationally catapulted by the galaxies’ merger.
“I’m skeptical that that would be an explanation,” Schlegel told reporters. “The more interesting possibility is the supermassive black hole itself has actually reacted to all this mass coming in.”
Follow-up observations of NGC 5195 in other wavelengths of light should flesh out scientists’ understanding of what is happening.
“It gives us a local object to study,” Schlegel said.
In related research, scientists found a supermassive black hole that may have been stripped of surrounding stars by a companion black hole. The pair, located about 1 billion light years away, co-reside in the galaxy SDSS J1126+2944.
The rare pair -- one of only 12 known galaxies with two supermassive black holes -- likely are the result of two galaxies merging, astrophysicist Julie Comerford, with the University of Colorado, Boulder, said at the AAS conference.
Scientists aren’t sure why one of the galaxy’s black holes has 500 times fewer stars than its mate.
One option is that is extreme gravitational and tidal forces, caused by the galaxies’ merger, have ripped away most of the stars from one black hole.
Another possibility is that the star-starved black hole is actually a rare “intermediate” black hole, with a mass of 100- to 1 million times the mass of the sun. If so, the smaller black hole likely came from a dwarf galaxy, with proportionally fewer stars.
“Intermediate mass black holes are hard to find ... and it’s hard to know where to look for them,” Comerford said
If the galaxy has an intermediate black hole, it likely will eventually merge with its supermassive sister, creating an even bigger black hole, Comerford added.
The research was presented at the AAS meeting and appears in the Nov. 10 issue of Astrophysical Journal.