Huge "balloon-like structures" have been spotted in the middle of our Milky Way galaxy, scientists say.
The pair of vast bubbles – which stretch for hundreds of light years – are throwing out radio signals and are some of the biggest features ever found at the centre of our galaxy.
They are so huge that they dwarf all of the other radio structures around the middle of our galactic neighbourhood.
They were probably born after a huge energetic burst that exploded near the supermassive black hole that floats at the centre of the Milky Way, researchers said.
"The centre of our galaxy is relatively calm when compared to other galaxies with very active central black holes," said Ian Heywood of the University of Oxford, who is the lead author of an article in the journal Nature describing the discovery.
"Even so, the Milky Way's central black hole can - from time to time - become uncharacteristically active, flaring up as it periodically devours massive clumps of dust and gas. It's possible that one such feeding frenzy triggered powerful outbursts that inflated this previously unseen feature."
The vast structure was spotted by the South African Radio Astronomy Observatory (SARAO) MeerKAT telescope, which Professor Heywood and his team used to map the regions found in the middle of our galaxy. They did so by looking for radio emissions at a very specific wavelength – they can be used to find particularly energetic regions in space, looking through the dense clouds that block us from being able to see the middle of the galaxy by looking for light.
Related Slideshow: Spectacular images from space (Provided by Photo Services)
Hurricane Dorian
Celebrating Spitzer's Sweet Sixteen
Full Infrared View of the M81 Galaxy
Hurricane Dorian's Eye
What Are We Looking At?
A Passing Fancy
Caught in the Act
NGC 3351, also known as Messier 95, was first discovered in 1781 by Pierre Méchain, a French astronomer and surveyor who worked alongside Charles Messier. NGC 3351 is a type of galaxy known as a barred spiral galaxy and it is located in the constellation of Leo (The Lion). New observations of this object have shown stellar feedback in action. Stellar feedback is the process of redistributing energy into the interstellar medium (the space in between the stars) within star-forming galaxies. In this particular galaxy, star formation is occurring in the ring surrounding the galaxy nucleus at such a violent rate that massive bubbles of hot gas can actually be seen being ejected.
Engines Ready
'First Light' From Chandra
NASA’s Chandra X-ray Observatory has captured many spectacular images of cosmic phenomena over its two decades of operations, but perhaps its most iconic is the supernova remnant Cassiopeia A. Located about 11,000 light-years from Earth, Cas A (as it’s nicknamed) is the glowing debris field left behind after a massive star exploded. When the star ran out of fuel, it collapsed onto itself and blew up as a supernova, possibly briefly becoming one of the brightest objects in the sky. (Although astronomers think that this happened around the year 1680, there are no verifiable historical records to confirm this.) The shock waves generated by this blast supercharged the stellar wreckage and its environment, making the debris glow brightly in many types of light, particularly X-rays. Shortly after Chandra was launched aboard the Space Shuttle Columbia on July 23, 1999, astronomers directed the observatory to point toward Cas A.
It was featured in Chandra's official “First Light” image, released Aug. 26, 1999, and marked a seminal moment not just for the observatory, but for the field of X-ray astronomy.
Image credit: X-ray: NASA/CXC/RIKEN/T. Sato et al.; Optical: NASA/STScI
Blazing a Safe Trail
The Northrop Grumman built attitude control motor (ACM) on Orion's launch abort system was successfully tested on August 22, at their facility in Elkton, Maryland. The 30-second trial by fire was the second to last test before it’s qualified for human spaceflight on Artemis 2 -- the first mission with astronauts. During the static test, the ACM produced more than 7,000 pounds of thrust from eight valves, providing enough force to steer Orion and its crew to a safe distance.
The launch abort system is designed to transport Orion and its crew to safety in the event of an emergency during launch or ascent. It consists of three solid rocket motors: the abort motor pulls the crew module away from the launch vehicle; the ACM steers and orients the capsule; then the jettison motor ignites to separate the launch abort system from Orion for parachute deployment and a safe crew landing. All three motors will be certified for future crewed flights after qualification tests are completed later this year. The launch abort system was stress tested earlier this year during the successful Ascent Abort-2 test. These achievements brings Orion closer to safe flights with astronauts, paving the way for the first woman and the next man to land on the Moon by 2024.
Comet Capture
Rolling Stones Rock
This animation illustrates NASA's InSight lander touching down on Mars, causing a rock to roll 3 feet (1 meter) as the lander touched down on Mars on Nov. 26, 2018. A little bigger than a golf ball, the rock was later nicknamed "Rolling Stones Rock" by the InSight team in honor of The Rolling Stones. A series of 10 or so divots marked the rock's course after being set in motion by the landing. It's the farthest NASA has seen a rock roll after landing a spacecraft on another planet.
Though fitting, "Rolling Stones Rock" is not an official designation by the International Astronomical Union, which is responsible to approving the names given to geographical and geological features on other planets.
The rock was imaged by the Instrument Deployment Camera (IDC) on InSight's robotic arm, which is not visible here.
Galactic Center
Connecting the Webb
Reaching a major milestone, engineers have successfully connected the two halves of the NASA/ESA/CSA James Webb Space Telescope for the first time at Northrop Grumman’s facilities in Redondo Beach, California. Once it reaches space, Webb will explore the cosmos using infrared light, from planets and moons within our Solar System to the most ancient and distant galaxies. To combine both halves of Webb, engineers carefully lifted the telescope (which includes the mirrors and science instruments) above the already-combined sunshield and spacecraft using a crane.
Team members slowly guided the telescope into place, ensuring that all primary points of contact were perfectly aligned and seated properly. The observatory has been mechanically connected; next steps will be to electrically connect the halves, and then test the electrical connections. Later, engineers will fully deploy the intricate five-layer sunshield, which is designed to keep Webb's mirrors and scientific instruments cold by blocking infrared light from the Earth, Moon and Sun. The ability of the sunshield to deploy to its correct shape is critical to mission success. Webb is scheduled for launch on a European Ariane 5 rocket from French Guiana in March 2021.
Capturing a Dying Star
This atmospheric image taken with the NASA/ESA Hubble Space Telescope shows a dark, gloomy scene in the constellation of Gemini (the Twins). The subject of this image confused astronomers when it was first studied — rather than being classified as a single object, it was instead recorded as two objects, owing to its symmetrical lobed structure (known as NGC 2371 and NGC 2372, though sometimes referred to together as NGC 2371/2). These two lobes are visible to the lower left and upper right of the frame, and together form something known as a planetary nebula. Despite the name, such nebulas have nothing to do with planets; NGC 2371/2 formed when a Sun-like star reached the end of its life and blasted off its outer layers, shedding the constituent material and pushing it out into space to leave just a superheated stellar remnant behind.
This remnant is visible as the bright star at the center of the frame, sitting neatly between the two lobes. The structure of this region is complex. It is filled with dense knots of gas, fast-moving jets that appear to be changing direction over time, and expanding clouds of material streaming outwards on diametrically opposite sides of the remnant star. Patches of this scene glow brightly as the remnant star emits energetic radiation that excites the gas within these regions, causing it to light up. This scene will continue to change over the next few thousand years. Eventually the knotty lobes will dissipate completely, and the remnant star will cool and dim to form a white dwarf.
Text credit: ESA (European Space Agency)
Blue Bahamas
X-raying Stellar Remnants
This colorful spread of light specks is in fact a record of extremely powerful phenomena taking place in a galaxy known as Messier 83, or M83. Located some 15 million light-years away, M83 is a barred spiral galaxy, not dissimilar in shape from our own Milky Way, and currently undergoing a spur of star formation, with a handful of new stars being born every year. While the starry pattern of spiral arms is barely visible in this X-ray view obtained by ESA’s XMM-Newton space observatory, this kaleidoscopic image tells a different story about the stellar remnants in this galaxy.
Most of the dots in this view represent the end points of the life cycle of stars, including remnants of supernova explosions and binary systems featuring compact stellar remnants like neutron stars or black holes that are feeding on matter from a companion star. In particular, the large speck to the lower left of the galaxy’s central region is what astronomers call an ultra-luminous X-ray source, or ULX, a binary system where the compact remnant is accreting mass from its companion at a much higher rate than an ordinary X-ray binary.
The sources located in the reddish area at the center of the image correspond to objects located in the inner portions of M83. The majority of sources scattered across the image are located in the outskirts of the galaxy, but a few of those are foreground stars in our own galaxy, and others correspond to more distant galaxies in the background.
This RGB image combines nine XMM-Newton observations performed between 2003 and 2016 at energies of 0.2–2 keV (shown in red), 2–4.5 keV (shown in green), and 4.5–12 keV (shown in blue).
Stellar Families
Wildfires in Brazil
Cache and Carry
The bit carousel, which lies at the heart of Sample Caching System of NASA's Mars 2020 mission, is attached to the front end of the rover in the Spacecraft Assembly Facility's High Bay 1 at the Jet Propulsion Laboratory in Pasadena, California. The carousel contains all of the tools the coring drill uses to sample the Martian surface and is the gateway for the samples to move into the rover for assessment and processing. The image was taken on Aug. 5, 2019.
JPL is building and will manage operations of the Mars 2020 rover for the NASA Science Mission Directorate at the agency's headquarters in Washington.
Deployment test of Webb’s secondary mirror
The secondary mirror – visible in the top right corner of the image – is among the most important pieces of equipment on the NASA/ESA/CSA James Webb Space Telescope (JWST) and is essential to the success of the mission.
Folded together with the other observatory components during launch, the secondary mirror will be deployed as part of an intricate choreography that will bring the observatory to life once in space. When deployed, like in this view, it faces Webb’s iconic honeycomb-like pattern of 18 hexagonal, gold-coated primary mirror segments. This primary mirror structure is seen in the lower left of the image in its folded configuration, showing only 12 segments.
Once the observatory is in space, light from distant stars and galaxies will first reach its primary mirror, which reflect it into a focused beam towards the secondary mirror. From there, the beam is then sent through the ‘hole’ in the primary mirror structure into the tertiary and fine steering mirrors, and eventually to the four scientific instruments, which sit behind the primary mirror in this view.
Technicians and engineers recently tested a key part of the telescope unfolding choreography by successfully commanding Webb to deploy the support structure that holds its secondary mirror in place. This is a critical milestone in preparing the observatory for its journey to orbit, as the proper deployment and positioning of the telescope’s secondary mirror is critical to perform the mission’s revolutionary science.
New Portrait of Jupiter
Galaxy’s Outer Reaches
Believe it or not, this long, luminous streak, speckled with bright blisters and pockets of material, is a spiral galaxy like our Milky Way. But how could that be?
It turns out that we see this galaxy, named NGC 3432, oriented directly edge-on to us from our vantage point here on Earth. The galaxy’s spiral arms and bright core are hidden, and we instead see the thin strip of its very outer reaches. Dark bands of cosmic dust, patches of varying brightness and pink regions of star formation help with making out the true shape of NGC 3432 — but it’s still somewhat of a challenge! Because observatories such as the NASA/ESA Hubble Space Telescope have seen spiral galaxies at every kind of orientation, astronomers can tell when we happen to have caught one from the side.
The galaxy is located in the constellation of Leo Minor (the Lesser Lion). Other telescopes that have had NGC 3432 in their sights include those of the Sloan Digital Sky Survey, the Galaxy Evolution Explorer (GALEX) and the Infrared Astronomical Satellite (IRAS).
Text credit: ESA (European Space Agency)
Our Sun Today
NASA's Solar Dynamic Observatory was the first mission to be launched for NASA's Living With a Star (LWS) Program, and is designed to understand the causes of solar variability and its impacts on Earth. SDO launched on February 11, 2010, on its journey to help us understand the Sun's influence on Earth and Near-Earth space by studying the solar atmosphere on small scales of space and time and in many wavelengths simultaneously.
SDO's goal is to understand, driving towards a predictive capability, the solar variations that influence life on Earth and humanity's technological systems by determining how the Sun's magnetic field is generated and structured, and how this stored magnetic energy is converted and released into the heliosphere and geospace in the form of solar wind, energetic particles, and variations in the solar irradiance. Each day, SDO images the sun in a variety of wavelengths.
Image released on Aug. 6.
Ready to Launch
CubeSats Dance
On June 21, 2019, NASA demonstrated the first coordinated maneuver between two CubeSats in low-Earth orbit as part of NASA’s Optical Communications and Sensor Demonstration mission.
The twin spacecraft, each approximately the size of a tissue box, were orbiting Earth about 5.5 miles apart when they established a radio frequency communications cross-link to “talk” with each other. One spacecraft issued a command to the second to activate its thruster and close the gap between the two. The fuel tanks on both spacecraft are filled with water. During this propulsive maneuver, the water was converted to steam by the thrusters to propel the spacecraft.
"Demonstrations such as this will help advance technologies that will allow for greater and more extended use of small spacecraft in and beyond Earth-orbit," said Roger Hunter, program manager of the Small Spacecraft Technology program.
The demonstration was designed with a series of safeguards to ensure that only a pre-planned and authorized maneuver could take place. While it was choreographed by human operators on the ground, the demonstration shows it is possible for a series of propulsive maneuvers to be planned with onboard processing and executed cooperatively by a group of small spacecraft.
Cosmic Seagull
ISS Transiting the Sun
Amateur astrophotographer Javier Manteca captured this transit of the Sun on Aug. 2, at 17:10 CEST from Fuenlabrada, Spain.
The International Space Station regularly transits the Sun but often along a very narrow ground path, which makes it hard to record. Once you lock down the best viewing location on Earth, timing is a critical factor: transits of the Sun last only half a second. Using a DSLR camera attached to a 150/750 telescope recording in full HD at 30 frames per second, Javier was able to capture the 0.8 seconds it took for the Station to pass. The image is made up of those stacked frames.
Sideways Galaxy
Terra Cimmeria
Approaching the ISS
Sphere of Color
This image shows a snippet of the Sun up close, revealing a golden surface marked by a number of dark, blotchy sunspots, curving filaments, and lighter patches known as ‘plages’ – brighter regions often found near sunspots.
Laser Guide Star
Over the Moon
Moonrise
View of SLS on Mobile Launcher
Ahuna Mons on Ceres
Space Race
Seismic Waves Inside Mars
Beyond Mission Launch
There is no asking for a better launch date. ESA astronaut Luca Parmitano and fellow Expedition 60/61 crew NASA astronaut Drew Morgan and cosmonaut Alexander Skvortsov lifted off to the International Space Station on July 20, the 50th anniversary of the historic Apollo 11 Moon landing.
While others were attending anniversary events or pouring through memorabilia, Luca was strapped in the most reliable spacecraft to ferry humans back and forth to space.
The Soyuz MS-13 lifted off from Baikonur cosmodrome in Kazakhstan at 18:28 CEST.
Expedition 60
Chang’e-4 Lander
At a time when ESA is looking forward to future lunar exploration, it turns out there is already some small but crucial ESA-developed hardware in operation on the far side of the Moon.
China’s Chang’e-4 lander is running on a LEON2-FT microprocessor core, especially designed for space missions by ESA and sold commercially by the Microchip company – marketed as the AT697.
The ordinary computer chips you use every day in your phone or laptop would be rapidly degraded by the radiation and environmental extremes of space. Specialized chips are therefore essential for spacecraft
Chang’e-4 touched down inside the Von Kármán crater on the Moon’s far side near the south pole on 3 January 2019. The lander and the rover it delivered are currently hibernating during the lunar night, having survived seven month-long lunar days so far.
“Most ESA missions launched after about 2010 include at least one LEON chip, and hundreds of these radiation-hardened off-the-shelf chips have also been sold to space missions both in Europe and around the globe,” explains ESA microelectronics engineer Agustin Fernandez-Leon.
“This number increases to the thousands if we additionally count customisable fully programmable gate arrays using LEON cores,” adds ESA microelectronics engineer Roland Weigand. “The overall scale of usage is such that it is impractical to keep track of all the missions making use of our microprocessor technology, but it is always nice to find out.”
A Puzzle of 10 Million Stars
When observed with the unaided eye, Omega Centauri, the object in this image, appears as a fuzzy, faint star. But the blue orb we see here is, in fact, a collection of stars – 10 million of them. You cannot count them all, but in this sharp, beautiful image you can see a few of the numerous pinpoints of bright light that make up this unique cluster.
The image was taken by Wouter van Reeven, a software engineer at ESA's European Space Astronomy Centre near Madrid, Spain, during his recent visit to Chile to observe the July total solar eclipse. From his home base in Spain the cluster only grazes the horizon, making it near-impossible to image, but from the La Silla Observatory in Chile it was high in the sky, presenting the ideal opportunity to photograph it.
Apollo 11 Projected on the Washington Monument
The image of a Saturn V, the rocket that sent Apollo 11 into orbit on July 16, 1969, is projected on the Washington Monument on July 16.
Robotic Arm Over Mongolia
Aerogel Greenhouses for Mars?
Eclipse
Moon Covers Sun
Taking to the Skies
Stellar Fireworks Show
A Whirlpool Warhol
These four panels show the Whirlpool galaxy -- which is actually a pair of galaxies also known as Messier 51 and NGC 5194/5195 -- and how different wavelengths of light can reveal different features of a cosmic object. Located approximately 23 million light-years away, it resides in the constellation Canes Venatici.
The left image (a) shows the galaxy in visible light, from the Kitt Peak National Observatory 2.1-meter (6.8-foot) telescope and shows light at 0.4 microns (blue) and 0.7 microns (green). The next image (b) combines two visible-light wavelengths (in blue and green) and infrared light (in red). The infrared was captured by NASA's Spitzer Space Telescope and emphasizes how the dark dust veins that block our view in visible light begin to light up at these longer, infrared wavelengths.
The right two panels are composed entirely of Spitzer data. In the middle-right panel (c), we see three wavelengths of infrared light: 3.6 microns (shown in blue), 4.5 microns (green) and 8 microns (red). The blended light from the billions of stars in the Whirlpool is brightest at the shorter infrared wavelengths and appear as as a blue haze. The individual blue dots across the image are mostly nearby stars and a few distant galaxies. Red features (at 8 microns) show us dust composed mostly of carbon that is illuminated by the stars in the galaxy.
The far-right panel (d) expands our infrared view to include light at a wavelength of 24 microns (in red), which is particularly good for highlighting areas where the dust is especially hot. The bright reddish-white spots trace regions where new stars are forming and, in the process, heating their surroundings.
Coming In For a Landing
Earth and Moon
First Humans on Mars (Artist's Concept)
Mass Ejection
Using those techniques to look at the huge bubbles – examining their size and shape, and finding that they appear to be almost identical – the researchers were able to find evidence that they suggest shows they were formed in an intense eruption. That seems to have happened over a short period of time, but was so extreme that it punched through the matter of space.
"The shape and symmetry of what we have observed strongly suggests that a staggeringly powerful event happened a few million years ago very near our galaxy's central black hole," said William Cotton, an astronomer with the National Radio Astronomy Observatory in Charlottesville, Virginia, and co-author on the paper.
"This eruption was possibly triggered by vast amounts of interstellar gas falling in on the black hole, or a massive burst of star formation which sent shockwaves careening through the galactic centre. In effect, this inflated bubbles in the hot, ionized gas near the galactic centre, energizing it and generating radio waves that we could eventually detect here on Earth."
The space around our galaxy's black hole is very different to that everywhere else in the Milky Way, far more turbulent and active than any other part of the galaxy. It is also largely mysterious, since it can be so hard to see – there are huge, long and narrow filaments that have not been spotted elsewhere, and which researchers still do not understand.
The new structures could help illuminate those filaments. Both might have been formed by the same mysterious energetic event.
"The radio bubbles discovered by MeerKAT now shed light on the origin of the filaments," said Farhad Yusef-Zadeh at Northwestern University in Evanston, Illinois, and a co-author on the paper. "Almost all of the more than one hundred filaments are confined by the radio bubbles."
Until now, it was not possible to see the structures because they were behind the glare of bright signals coming from the middle of the galaxy. Scientists were able to use new techniques to look through those dazzling emissions and see the new, towering formations.
"These enormous bubbles have until now been hidden by the glare of extremely bright radio emission from the center of the galaxy," said Fernando Camilo of SARAO in Cape Town and co-author on the paper.
"Teasing out the bubbles from the background noise was a technical tour de force, only made possible by MeerKAT's unique characteristics and ideal location. With this unexpected discovery we're witnessing in the Milky Way a novel manifestation of galaxy-scale outflows of matter and energy, ultimately governed by the central black hole."
The new research is published today in Nature, and is written by authors from 15 different institutions. It is the first paper to detail research from the MeerKAT's full array since it was launched last year.
https://www.msn.com/en-us/news/technology/huge-structures-found-at-the-centre-of-our-milky-way-galaxy-scientists-say/ar-AAHbojj?ocid=st
2019-09-12 10:20:00Z
52780380632039
Bagikan Berita Ini
0 Response to "Huge 'structures' found at the centre of our Milky Way galaxy, scientists say - msnNOW"
Post a Comment