Heralding the growth of monster black holes pulling in surrounding material while belching out the cosmic x-ray background
Space news (astrophysics: x-ray bursts; detecting high-energy x-rays emitted by supermassive black holes) – searching the COSMOS field for elusive, high-energy x-rays with a high-pitched voice –
Astronomers searching for elusive, high-energy x-rays emitted by supermassive black holes recently made a discovery using NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR). A chorus of high-energy x-rays emitted by millions of supermassive black holes hidden within the cores of galaxies spread across a field of galaxies called the COSMOS field. Singing the elusive, high-pitched song of a phenomenon scientists call the cosmic x-ray background they emitted when they pulled surrounding matter closer. A significant step in resolving the high-energy x-ray background and understanding more about the feeding habits of supermassive black holes as they grow and evolve.
“We’ve gone from resolving just two percent of the high-energy X-ray background to 35 percent,” said Fiona Harrison, the principal investigator of NuSTAR at Caltech in Pasadena and lead author of a new study describing the findings in an upcoming issue of The Astrophysical Journal. “We can see the most obscured black holes, hidden in thick gas and dust.”
The Monster of the Milky Way, the supermassive black hole believed to reside at the core of our galaxy, bulked up by siphoning off surrounding gas and dust in the past and will continue to grow. The data obtained here by NASA’s NuSTAR will help scientists learn more concerning the growth and evolution of black holes and our host galaxy. It will also give astrophysicists more insight into the processes involved the next time the Monster of the Milky Way wakes up and decides to have a little snack.
“Before NuSTAR, the X-ray background in high energies was just one blur with no resolved sources,” said Harrison. “To untangle what’s going on, you have to pinpoint and count up the individual sources of the X-rays.”
NASA’s NuSTAR’s the first telescope capable of focusing high-energy x-rays into a sharp image, but it only gives us part of the picture. Additional research’s required to clear up the picture a little more and give us a better view of the real singers in the choir. NuSTAR should allow astronomers to decipher individual voices of x-ray singers in one of the cosmos’ rowdiest choirs.
“We knew this cosmic choir had a strong high-pitched component, but we still don’t know if it comes from a lot of smaller, quiet singers, or a few with loud voices,” said co-author Daniel Stern, the project scientist for NuSTAR at NASA’s Jet Propulsion Laboratory in Pasadena, California. “Now, thanks to NuSTAR, we’re gaining a better understanding of the black holes and starting to address these questions.”
Astronomers plan on collecting more data on the high-energy x-ray choir of the COSMOS field, which should help clear up a few mysteries surrounding the birth, growth, and evolution of black holes. Hopefully, it gives also gives us more clues to many of the mysteries we discover during the human journey to the beginning of space and time.
Plus nearly a thousand extremely bright, dusty objects nicknamed hot DOGS
Space news (All-sky surveys: infrared; candidate supermassive black holes and dust-obscured galaxies) – The visible universe –
Astronomers working with data provided by an infrared survey of the visible sky conducted by NASA’s Wide-field Infrared Survey Explorer (WISE) have identified millions of new candidates for the quasar section in the Galaxy Zoo. All-sky images taken by WISE revealed around 2.5 million candidate supermassive black holes actively feeding on material, some over 10 billion light-years away. They also pinpointed nearly a 1,000 very bright, extremely dusty objects nicknamed hot DOGS believed to be among the brightest galaxies discovered during the human journey to the beginning of space and time.
“These dusty, cataclysmically forming galaxies are so rare WISE had to scan the entire sky to find them,” said Peter Eisenhardt, lead author of the paper on the first of these bright, dusty galaxies, and project scientist for WISE at JPL. “We are also seeing evidence that these record setters may have formed their black holes before the bulk of their stars. The ‘eggs’ may have come before the ‘chickens.”
“WISE has exposed a menagerie of hidden objects,” said Hashima Hasan, WISE program scientist at NASA Headquarters in Washington. “We’ve found an asteroid dancing ahead of Earth in its orbit, the coldest star-like orbs known and now, supermassive black holes and galaxies hiding behind cloaks of dust.”
Astronomers detected Trojan asteroid TK7 in October 2010 in images of the sky taken by NASA’s WISE, before verifying its existence on optical images taken by the Canada-France-Hawaii Telescope. Additional study and computer modeling indicate Earth’s small dance partner should stay in a safe orbit for the next 10,000 years at least.
In March 2014 astronomers studying infrared images taken by WISE announced the discovery of around 3,500 new stars lying within 500 light-years of Earth. At the same time, they searched the data looking for evidence of Planet X, or Nemesis, the mythical planet some believe to exist somewhere beyond the orbit of Pluto. Scientists analyzed millions of infrared images taken by WISE out to a distance well beyond the orbit of our former ninth planet. They didn’t detect any objects the size of a planet out to a distance of around 25,000 times the distance between the Earth and Sol. Many times beyond the orbit of Pluto. No Planet X was found.
The vast majority of the latest candidates for the Galaxy Zoo are objects previously undetected by astronomers due to dust blocking visible light. Fortunately, the infrared eyes of WISE detected glowing dust around the candidates, which allowed scientists to detect them. These latest findings are clues astronomers use to better understand the processes creating galaxies and the monster black holes residing in their centers.
“We’ve got the black holes cornered,” said Daniel Stern of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., lead author of the WISE black hole study and project scientist for another NASA black-hole mission, the Nuclear Spectroscopic Telescope Array (NuSTAR). “WISE is finding them across the full sky, while NuSTAR is giving us an entirely new look at their high-energy X-ray light and learning what makes them tick.”
Organizing the Monster Zoo
The Monster of the Milky Way, the estimated 4 million solar mass black hole astronomers believe resides at the center, periodically feeds upon material falling too deep into its gravity well, and heats up surrounding disks of dust and gas. Astronomers have even witnessed 1 billion solar mass monster black holes change their surrounding environments enough to shut down star formation processes in their host galaxy. Now, astronomers need to go through the millions of candidates and put them in the correct section of the zoo. We might even need to open a few new sections to accommodate unusual candidates found during a closer examination.
You can learn more about supermassive black holes here.
Astronomers study 40 X-ray binaries comprised of black hole or neutron star feeding on material from companion star
Space news (February 05, 2016) – 2.5 million light-years away in Andromeda –
Astronomers using NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) to study 40 X-ray binaries in Andromeda Galaxy (M31). Astrophysicists study the critical role these energetic, intense sources of X-rays could have played in heating the intergalactic gasses in which the first galaxies were born. A study expected to help scientists view more distant galaxies and develop current and new theories on cosmic evolution.
“Andromeda is the only large spiral galaxy where we can see individual X-ray binaries and study them in detail in an environment like our own,” said Daniel Wik of NASA Goddard Space Flight Center in Greenbelt, Maryland, who presented the results at the 227th meeting of American Astronomical Society in Kissimmee, Florida. “We can then use this information to deduce what’s going on in more distant galaxies, which are harder to see.”
Andromeda and the Milky Way are fated to collide billions of years in the future, which will disrupt their spiral structures. Andromeda is slightly bigger than our home galaxy and is viewable from Earth by the naked human eye on dark, clear nights. The galaxy that results from their fated meeting in the dark of space will look nothing like the pair as we see them now. Watch this video on the Hubble site called “Clash of the Titans: Milky Way & Andromeda Collision“.
Astronomers are currently going over the data obtained through their use of NuSTAR to study the 40 X-ray binaries in Andromeda. Astrophysicists are identifying the fraction containing black holes as compared to neutron stars in order to better understand X-ray binaries as a whole.
“We have come to realize in the past few years that it is likely the lower-mass remnants of normal stellar evolution, the black holes, and neutron stars, may play a crucial role in heating of the intergalactic gas at very early times in the universe, around the cosmic dawn,” said Ann Hornschemeier of NASA Goddard, the principal investigator of the NuSTAR Andromeda studies.
She continued, “Observations of local populations of stellar-mass-sized black holes and neutron stars with NuSTAR allow us to figure out just how much power is coming out from these systems. The new research also reveals how Andromeda may differ from our Milky Way.“
Fiona Harrison, the principal investigator of the NuSTAR mission, added, “Studying the extreme stellar populations in Andromeda tells us about how its history of forming stars may be different than in our neighborhood.”
You can learn more about the mission of NASA’s NuSTARhere.
Discover the history and future plans of NASA here.
Bizarre and mysterious stellar objects, studying black holes keeps astronomers up all night. One of the more puzzling mysteries of these unique objects are gigantic flares of X-rays (relativistic jets) detected erupting from disks of hot, glowing dust surrounding them. X-ray flares astronomers are presently studying in order to better understand these enigmatic, yet strangely attractive stellar objects.
Astronomers observing supermassive black holes using NASA’s Swift spacecraft and Nuclear Spectroscopic Telescope Array (NuSTAR) recently caught one in the middle of a gigantic X-ray flare. After analysis, they discovered this particular flare appeared to be a result of theCorona surrounding the supermassive black hole – region of highly energetic particles – being launched into space. A result making scientists and astronomers rethink their theories on how relativistic jets are created and sustained.
This result suggests to scientists that supermassive black holes emit X-ray flares when highly energized particles (Coronas) are launched away from the black hole. In this particular case, X-ray flares traveling at 20 percent of the speed of light, and directly pointing toward Earth. The ejection of the Corona caused the X-ray light emitted to brighten a little in an effect called relativistic Doppler boosting. This slightly brighter X-ray light has a different spectrum due to the motion of the Corona, which helped astronomers detect this unusual phenomenon leaving the disk of dust and gas surrounding this supermassive black hole.
“This is the first time we have been able to link the launching of the Corona to a flare,” said Dan Wilkins of Saint Mary’s University in Halifax, Canada, lead author of a new paper on the results appearing in the Monthly Notices of the Royal Astronomical Society. “This will help us understand how supermassive black holes power some of the brightest objects in the universe.“
Astronomers currently propose two different scenarios for the source ofcoronas surrounding supermassive black holes. The “lamppost” scenario indicates coronas are analogous to light bulbs sitting above and below the supermassive black hole along its axis of rotation. This idea proposes coronas surrounding supermassive black holes are spread randomly as a large cloud or a “sandwich” that envelopes the disk of dust and material surrounding the black hole. Some astronomers think coronas surrounding supermassive black holes could alternate between both the lamppost and sandwich configurations.
The latest data seems to lean toward the “lamppost” scenario and gives us clues to how the coronas surrounding black holes move. More observations are needed to ascertain additional facts concerning this unusual phenomenon and how massive X-ray flares and gamma rays emitted by supermassive black holes are created.
“Something very strange happened in 2007, when Mrk 335 faded by a factor of 30. What we have found is that it continues to erupt in flares but has not reached the brightness levels and stability seen before,” said Luigi Gallo, the principal investigator for the project at Saint Mary’s University. Another co-author, Dirk Grupe of Morehead State University in Kentucky, has been using Swift to regularly monitor the black hole since 2007.
“The Corona gathered inward at first and then launched upwards like a jet,” said Wilkins. “We still don’t know how jets in black holes form, but it’s an exciting possibility that this black hole’s Corona was beginning to form the base of a jet before it collapsed.”
“The nature of the energetic source of X-rays we call the Corona is mysterious, but now with the ability to see dramatic changes like this we are getting clues about its size and structure,” said Fiona Harrison, the principal investigator of NuSTAR at the California Institute of Technology in Pasadena, who was not affiliated with the study.
Astronomers will now continue their study of supermassive black holes in the cosmos in order to remove the veil of mystery surrounding the X-ray flares they emit and other bizarre mysteries surrounding these enigmatic stellar objects. In particular, they would love to discover the reasons for the ejection of Coronas surrounding black holes.
New programs selected will study neutron star-black hole binary systems, the expansion of space and galaxies in the early cosmos, the star formation cycle of the Milky Way and more
Space news (October 29, 2015) – NASA Headquarters, Washington, D.C. –
NASA’s Explorers Program was designed in the spirit of the first explorers who traveled across the deep, dark and mysterious oceans and lands in search of the unknown. Thousands of years ago, archaeologists believe ancient humans used the stars, ocean currents and waves to navigate across the seas to new lands. Today, astronauts and scientists taking part in NASA’s Explorers Program travel across space-time to stellar objects in the sky using scientific instruments and spacecraft ancient humans would perceive as God-like.
NASA’s Explorers Program began with the launch of the first spacecraft designed by engineers and scientists working for the Army Ballistic Missile Agency on January 31, 1958, making it the oldest continuously running low-cost NASA program in history.Fittingly called “Explorer”, since this first spacecraft over 90 space missions to the stars have been designed and launched as part of the Explorers Program. Space missions to the stars that have made startling discoveries about Earth’s magnetosphere and gravity field, the composition of the solar wind and solar plasma erupting from the surface of the Sun. They have traveled to other planets in the solar system and studied radio and gamma-ray astronomy, and in the future will enable the human journey to the beginning of space and time.
NASA recently announced five less-expensive Explorers Program missions designed to the fill the scientific and technical gaps their more involved and expensive space missions. The selected space missions will examine polarized X-ray emissions emitted by binary star systems composed of a neutron star and black hole and the expansion of spacetime during the early moments of the universe. They’ll also take a closer look at the formation of galaxies during the first moments of the cosmos and the birth and life cycle of stars in the Milky Way.
Located in the Goddard Space Flight Center in Greenbelt, MD, the Explorers Program provides an opportunity for human robotic-envoys to make frequent trips into space for scientific explorations of the solar system and cosmos. Relatively low-cost, small to medium size space missions requiring fewer resources and time compared to larger missions to get off the drawing board and into space.
“The Explorers Program brings out some of the most creative ideas for missions to help unravel the mysteries of the Universe,” said John Grunsfeld, NASA’s Associate Administrator for Science at NASA Headquarters, in Washington. “The program has resulted in great missions that have returned transformational science, and these selections promise to continue that tradition.”
Now, each of the three selected Small Explorers mission proposals will receive $1 million to conduct an 11-month mission concept study, while the two Missions of Opportunity proposals receive $250,000 to conduct an 11-month mission implementation concept study.
During the months ahead, NASA scientists will conduct concept studies and detailed evaluations of each proposal selected. After this, they’ll select one mission of each type to proceed to construction and launch, by 2020 at the earliest. In the end, the total cost for this part of the Explorers Program is capped at just around $190 million for the two missions selected: $125 million for each Small Explorers mission and $65 million for each Mission of Opportunity.
The three Small ExplorersProgram missions selected are:
SPHEREx explores the origin and evolution of the cosmos and galaxies in the sky and the possibility planets around other stars could harbor life.
James Bock of the California Institute of Technology in Pasadena, California is the main scientist on this mission.
Imaging X-ray Polarimetry Explorer (IXPE)
IXPE studies the processes leading to X-ray emission in neutron stars, pulsar wind nebulae, and stellar and supermassive black holes using X-ray polarimetry, the measurement, and interpretation of the polarization of electromagnetic waves.
Martin Weisskopf of NASA’s Marshall Space Flight Center in Huntsville, Alabama is the main scientist on this project.
Polarimeter for Relativistic Astrophysical X-ray Sources (PRAXyS)
PRAXyS uses X-ray polarimetry to study the geometry and behavior of X-ray sources emitted from supermassive black holes, pulsars, magnetars and supernovae.
The two Missions of Opportunity proposals selected are:
GUSTO is an observatory held aloft by a balloon designed to detect high-frequency radio emission from sources in our Milky Way and the Large MagellanicCloud in order to study the life cycle of interstellar material.
Christopher Walker of the University of Arizona in Tucson is the main scientists on this mission.
LiteBIRD is a Japanese space mission with US contributions designed to map polarized fluctuations in the Cosmic Microwave Background in order to search for signs of gravitation waves created during inflation in an effort to better understand the events that occurred during the first moments of the cosmos.
Adrian Lee of the University of California at Berkeley is a main scientist on this mission.
For more information on NASA’s Explorers Program, go here.
To learn more about NASA’s mandate to travel to the stars and beyond visit here.
Learn more about the Goddard Space Flight Center here.
Discover and explore the Marshall Space Flight Center here.
Space scientists have debated the nature and origin of high energy ultra-luminous x-ray sources for years
Space news (Oct. 28, 2014) –
Space scientists have been looking at celestial objects called ultraluminous x-ray sources (ULXs) for years in search of answers to the mystery surrounding their nature and origin. Celestial bodies radiating enormous amounts of high-energy x-rays, astronomers have been studying three nearby ULXs changing thoughts and present theory on these energetic characters.
Space scientists using the Chandra X-ray Observatory, Hubble Space Telescope, Swift Gamma-ray Burst Explorer and XMM-Newton Space Observatory have been studying two ULXs discovered in Andromeda galaxy (M31). The first is called CXOM31 and was discovered in 2009 using the Chandra X-ray Space Observatory. The second, XMMU, was discovered on Jan. 15, 2014 by the European Space Agency’s XMM-Newton spacecraft.
Space scientists believe both ULXs they observe in Andromeda are binary star systems with a black hole rapidly accreting (consuming) material from its neighbor at a rate near the theoretical Eddington limit (the maximum accretion rate of a black hole).
“There are four black hole binaries within our own galaxy that have been observed accreting at these extreme rates,” said Matthew Middleton, an astronomer at the Anton Pannekoek Astronomical Institute in Amsterdam. “Gas and dust in our own galaxy interfere with our ability to probe how matter flows into ULXs, so our best glimpse of these processes comes from sources located out of the plane of our galaxy, such as those in M31.”
“As gas spirals toward a black hole, it becomes compressed and heated, eventually reaching temperatures where it emits X-rays. As the rate of matter ingested by the black hole increases, so does the X-ray brightness of the gas. At some point, the X-ray emission becomes so intense that it pushes back on the inflowing gas, theoretically capping any further increase in the black hole’s accretion rate. Astronomers refer to this as the Eddington limit, after Sir Arthur Eddington, the British astrophysicist who first recognized a similar cutoff to the maximum luminosity of a star.”
“Black-hole binaries in our galaxy that show accretion at the Eddington limit also exhibit powerful radio-emitting jets that move near the speed of light,” Middleton said. “Although astronomers know little about the physical nature of these jets, detecting them at all would confirm that the ULX is accreting at the limit and identify it as a stellar mass black hole.”
Space scientists operating NASA’s Nuclear Array (NuSTAR) have also found the brightest ULX on record near the center of galaxy Messier 82 (M82) 12 million light-years away. Called M82 X-2, they believe this particular object is actually a dead pulsating star called a pulsar, rather than a binary star system with a black hole accreting material from its neighbor.
“Astronomers have found a pulsating, dead star beaming with the energy of about 10 million suns. This is the brightest pulsar – a dense stellar remnant left over from a supernova explosion – ever recorded. The discovery was made with NASA’s Nuclear Spectroscopic Telescope Array, or NuSTAR.”
“You might think of this pulsar as the ‘Mighty Mouse’ of stellar remnants,” said Fiona Harrison, the NuSTAR principal investigator at the California Institute of Technology in Pasadena, California. “It has all the power of a black hole, but with much less mass.”
This ULX being something other than a binary star system with an accreting black hole is surprising to astronomers. They’ll have to rethink present theories on the nature and origin of these mysterious celestial objects.
“The pulsar appears to be eating the equivalent of a black hole diet,” said Harrison. “This result will help us understand how black holes gorge and grow so quickly, which is an important event in the formation of galaxies and structures in the universe.”
“ULXs are generally thought to be black holes feeding off companion stars — a process called accretion. They also are suspected to be the long-sought-after “medium-sized” black holes – missing links between smaller, stellar-size black holes and the gargantuan ones that dominate the hearts of most galaxies. But research into the true nature of ULXs continues toward more definitive answers.”
“We took it for granted that the powerful ULXs must be massive black holes,” said lead study author Matteo Bachetti, of the University of Toulouse in France. “When we first saw the pulsations in the data, we thought they must be from another source.”
“Having a diverse array of telescopes in space means that they can help each other out,” said Paul Hertz, director of NASA’s astrophysics division in Washington. “When one telescope makes a discovery, others with complementary capabilities can be called in to investigate it at different wavelengths.”
Space scientists will now use NASA’s complete array of astronomical equipment and spacecraft to look at how this dead star is able to radiate x-rays so intensely. Plans are for NuSTAR, the Swift Gamma-ray Burst Explorer, and Chandra X-ray Space Observatory to have a look at the weird behavior of M82 X-2.
They’ll also start looking at other ULXs to see if they can find anymore that are pulsars, rather than a binary star system with an accreting black hole. This research could open a window of discovery on the true nature and origin of these energetic and enigmatic celestial objects.