Star spotted speeding near black hole at centre of Milky Way

Star spotted speeding near black hole at centre of Milky Way

Chile’s Very Large Telescope tracks S2 star as it reaches mind-boggling speeds by supermassive black hole

Source: www.theguardian.com/science/2018/jul/26/star-spotted-speeding-near-milky-way-black-hole-for-first-time

Star spotted speeding near black hole at centre of Milky Way Chile’s Very Large Telescope tracks S2 star as it reaches mind-boggling speeds by supermassive black hole Source: www.theguardian.com/science/2018/jul/26/star-spotted-speeding-near-milky-way-black-hole-for-first-time

The Octonion Math That Could Underpin Physics | Quanta Magazine

 

The Octonion Math That Could Underpin Physics | Quanta Magazine

New findings are fueling an old suspicion that fundamental particles and forces spring from strange eight-part numbers called “octonions.”

Source: www.quantamagazine.org/the-octonion-math-that-could-underpin-physics-20180720/

  The Octonion Math That Could Underpin Physics | Quanta Magazine New findings are fueling an old suspicion that fundamental particles and forces spring from strange eight-part numbers called “octonions.” Source: www.quantamagazine.org/the-octonion-math-that-could-underpin-physics-20180720/

Martian atmosphere behaves as one

 

Martian atmosphere behaves as one

New research using a decade of data from ESA’s Mars Express has found clear signs of the complex martian atmosphere acting as a single, interconnected system, with processes occurring at low and mid levels significantly affecting those seen higher up.

Source: m.esa.int/Our_Activities/Space_Science/Mars_Express/Martian_atmosphere_behaves_as_one

  Martian atmosphere behaves as one New research using a decade of data from ESA’s Mars Express has found clear signs of the complex martian atmosphere acting as a single, interconnected system, with processes occurring at low and mid levels significantly affecting those seen higher up. Source: m.esa.int/Our_Activities/Space_Science/Mars_Express/Martian_atmosphere_behaves_as_one

Supersharp Images from New VLT Adaptive Optics

Supersharp Images from New VLT Adaptive Optics

ESO’s Very Large Telescope (VLT) has achieved first light with a new adaptive optics mode called laser tomography — and has captured remarkably sharp test images of the planet Neptune, star clusters and other objects. The pioneering MUSE instrument in Narrow-Field Mode, working with the GALACSI adaptive optics module, can now use this new technique to correct for turbulence at different altitudes in the atmosphere. It is now possible to capture images from the ground at visible wavelengths that are sharper than those from the NASA/ESA Hubble Space Telescope. The combination of exquisite image sharpness and the spectroscopic capabilities of MUSE will enable astronomers to study the properties of astronomical objects in much greater detail than was possible before.

Source: www.eso.org/public/news/eso1824/

Supersharp Images from New VLT Adaptive Optics ESO’s Very Large Telescope (VLT) has achieved first light with a new adaptive optics mode called laser tomography — and has captured remarkably sharp test images of the planet Neptune, star clusters and other objects. The pioneering MUSE instrument in Narrow-Field Mode, working Continue Reading

Twelve new moons orbiting Jupiter have been found!!

Twelve new moons orbiting Jupiter have been found—11 “normal” outer moons, and one that they’re calling an “oddball.”  This brings Jupiter’s total number of known moons to a whopping 79—the most of any planet in our Solar System.

A team led by Carnegie’s Scott S. Sheppard first spotted the moons in the spring of 2017 while they were looking for very distant Solar System objects as part of the hunt for a possible massive planet far beyond Pluto.  

In 2014, this same team found the object with the most-distant known orbit in our Solar System and was the first to realize that an unknown massive planet at the fringes of our Solar System, far beyond Pluto, could explain the similarity of the orbits of several small extremely distant objects. This putative planet is now sometimes popularly called Planet X or Planet Nine.  University of Hawaii’s Dave Tholen and Northern Arizona University’s Chad Trujillo are also part of the planet search team.

“Jupiter just happened to be in the sky near the search fields where we were looking for extremely distant Solar System objects, so we were serendipitously able to look for new moons around Jupiter while at the same time looking for planets at the fringes of our Solar System,” said Sheppard.

Gareth Williams at the International Astronomical Union’s Minor Planet Center used the team’s observations to calculate orbits for the newly found moons. 

“It takes several observations to confirm an object actually orbits around Jupiter,” Williams said. “So, the whole process took a year.”

Nine of the new moons are part of a distant outer swarm of moons that orbit it in the retrograde, or opposite direction of Jupiter’s spin rotation.  These distant retrograde moons are grouped into at least three distinct orbital groupings and are thought to be the remnants of three once-larger parent bodies that broke apart during collisions with asteroids, comets, or other moons. The newly discovered retrograde moons take about two years to orbit Jupiter.

Two of the new discoveries are part of a closer, inner group of moons that orbit in the prograde, or same direction as the planet’s rotation. These inner prograde moons all have similar orbital distances and angles of inclinations around Jupiter and so are thought to also be fragments of a larger moon that was broken apart. These two newly discovered moons take a little less than a year to travel around Jupiter.

 

Source : https://carnegiescience.edu/news/dozen-new-moons-jupiter-discovered-including-one-%E2%80%9Coddball%E2%80%9D

Twelve new moons orbiting Jupiter have been found—11 “normal” outer moons, and one that they’re calling an “oddball.”  This brings Jupiter’s total number of known moons to a whopping 79—the most of any planet in our Solar System. A team led by Carnegie’s Scott S. Sheppard first spotted the moons Continue Reading

The Gaia Sausage: The Major Collision That Changed the Milky Way Galaxy

 

The Gaia Sausage: The Major Collision That Changed the Milky Way Galaxy | Simons Foundation

The Gaia Sausage: The Major Collision That Changed the Milky Way Galaxy on Simons Foundation

An international team of astronomers has discovered an ancient and dramatic head-on collision between the Milky Way and a smaller object, dubbed the “Sausage” galaxy. The cosmic crash was a defining event in the early history of the Milky Way and reshaped the structure of our galaxy, fashioning both its inner bulge and its outer halo, the astronomers report in a series of new papers.

The astronomers propose that around 8 billion to 10 billion years ago, an unknown dwarf galaxy smashed into our own Milky Way. The dwarf did not survive the impact: It quickly fell apart, and the wreckage is now all around us.

“The collision ripped the dwarf to shreds, leaving its stars moving in very radial orbits” that are long and narrow like needles, said Vasily Belokurov of the University of Cambridge and the Center for Computational Astrophysics at the Flatiron Institute in New York City. The stars’ paths take them “very close to the center of our galaxy. This is a telltale sign that the dwarf galaxy came in on a really eccentric orbit and its fate was sealed.”

The new papers in the Monthly Notices of the Royal Astronomical Society, The Astrophysical Journal Letters and arXiv.org outline the salient features of this extraordinary event. Several of the papers were led by Cambridge graduate student GyuChul Myeong. He and colleagues used data from the European Space Agency’s Gaia satellite. This spacecraft has been mapping the stellar content of our galaxy, recording the journeys of stars as they travel through the Milky Way. Thanks to Gaia, astronomers now know the positions and trajectories of our celestial neighbors with unprecedented accuracy.

The paths of the stars from the galactic merger earned them the moniker “the Gaia Sausage,” explained Wyn Evans of Cambridge. “We plotted the velocities of the stars, and the sausage shape just jumped out at us. As the smaller galaxy broke up, its stars were thrown onto very radial orbits. These Sausage stars are what’s left of the last major merger of the Milky Way.”

The Milky Way continues to collide with other galaxies, such as the puny Sagittarius dwarf galaxy. However, the Sausage galaxy was much more massive. Its total mass in gas, stars and dark matter was more than 10 billion times the mass of our sun. When the Sausage crashed into the young Milky Way, its piercing trajectory caused a lot of mayhem. The Milky Way’s disk was probably puffed up or even fractured following the impact and would have needed to regrow. And Sausage debris was scattered all around the inner parts of the Milky Way, creating the ‘bulge’ at the galaxy’s center and the surrounding ‘stellar halo.’

Sausage Stars: When looking at the distribution of star velocities in the Milky Way, the stars of the Sausage galaxy form a characteristic sausage-like shape. This unique shape is caused by the strong radial motions of the stars. As the sun lies in the center of this enormous cloud of stars, the distribution does not include the slowed-down stars currently making a U-turn back toward the galaxy’s center.Credit: V. Belokurov (Cambridge, UK) and Gaia/ESA

Numerical simulations of the galactic mashup can reproduce these features, said Denis Erkal of the University of Surrey. In simulations run by Erkal and colleagues, stars from the Sausage galaxy enter stretched-out orbits. The orbits are further elongated by the growing Milky Way disk, which swells and becomes thicker following the collision.

Evidence of this galactic remodeling is seen in the paths of stars inherited from the dwarf galaxy, said Alis Deason of Durham University. “The Sausage stars are all turning around at about the same distance from the center of the galaxy.” These U-turns cause the density in the Milky Way’s stellar halo to decrease dramatically where the stars flip directions. This discovery was especially pleasing for Deason, who predicted this orbital pileup almost five years ago. The new work explains how the stars fell into such narrow orbits in the first place.

The new research also identified at least eight large, spherical clumps of stars called globular clusters that were brought into the Milky Way by the Sausage galaxy. Small galaxies generally do not have globular clusters of their own, so the Sausage galaxy must have been big enough to host a collection of clusters.

“While there have been many dwarf satellites falling onto the Milky Way over its life, this was the largest of them all,” said Sergey Koposov of Carnegie Mellon University, who has studied the kinematics of the Sausage stars and globular clusters in detail.

  The Gaia Sausage: The Major Collision That Changed the Milky Way Galaxy | Simons Foundation The Gaia Sausage: The Major Collision That Changed the Milky Way Galaxy on Simons Foundation An international team of astronomers has discovered an ancient and dramatic head-on collision between the Milky Way and a Continue Reading

MeerKAT radio telescope inaugurated in South Africa – reveals clearest view yet of center of the Milky Way – SKA SA

MeerKAT radio telescope inaugurated in South Africa – reveals clearest view yet of center of the Milky Way – SKA SA

Deputy President of the Republic of South Africa, Mr David Mabuza, today officially inaugurated the MeerKAT radio telescope. After a decade in design and construction, this project of South Africa’s Department of Science and Technology has now begun science operations. At the launch event, a panorama obtained with the new telescope was unveiled that reveals extraordinary detail in the region surrounding the supermassive black hole at the centre of our Milky Way Galaxy. This is one of several very exciting new views of the Universe already observed by the telescope.

 

“We wanted to show the science capabilities of this new instrument”, says Fernando Camilo, chief scientist of the South African Radio Astronomy Observatory (SARAO), which built and operates MeerKAT in the semi-arid Karoo region of the Northern Cape. “The centre of the galaxy was an obvious target: unique, visually striking and full of unexplained phenomena – but also notoriously hard to image using radio telescopes”, according to Camilo. The centre of the Milky Way, 25,000 light-years away from Earth and lying behind the constellation Sagittarius (the “Teapot”), is forever enshrouded by intervening clouds of gas and dust, making it invisible from Earth using ordinary telescopes. However, infrared, X-ray, and in particular, radio wavelengths penetrate the obscuring dust and open a window into this distinctive region with its unique 4 million solar mass black hole. “Although it’s early days with MeerKAT, and a lot remains to be optimised, we decided to go for it – and were stunned by the results.”

“This image is remarkable”, says Farhad Yusef-Zadeh of Northwestern University in Evanston, Illinois, one of the world’s leading experts on the mysterious filamentary structures present near the central black hole but nowhere else in the Milky Way. These long and narrow magnetised filaments were discovered in the 1980s using the Very Large Array (VLA) radio telescope in New Mexico, but their origin has remained a mystery. “The MeerKAT image has such clarity”, continues Yusef-Zadeh, “it shows so many features never before seen, including compact sources associated with some of the filaments, that it could provide the key to cracking the code and solve this three-decade riddle”.

Yusef-Zadeh adds that “MeerKAT now provides an unsurpassed view of this unique region of our galaxy. It’s an exceptional achievement, congratulations to our South African colleagues. They’ve built an instrument that will be the envy of astronomers everywhere and will be in great demand for years to come”.

MeerKAT radio telescope inaugurated in South Africa – reveals clearest view yet of center of the Milky Way – SKA SA Deputy President of the Republic of South Africa, Mr David Mabuza, today officially inaugurated the MeerKAT radio telescope. After a decade in design and construction, this project of South Continue Reading

‘Ghost’ particles from black-hole jetstream found in Antarctic

‘Ghost’ particles from black-hole jetstream found in Antarctic

Neutrinos are the universe’s ghosts. Trillions of these particles move through us all the time at close to the speed of light. We cannot see, feel or sense them

Source: www.smh.com.au/national/ghost-particles-from-black-hole-jetstream-found-in-arctic-20180712-p4zr4t.html

‘Ghost’ particles from black-hole jetstream found in Antarctic Neutrinos are the universe’s ghosts. Trillions of these particles move through us all the time at close to the speed of light. We cannot see, feel or sense them Source: www.smh.com.au/national/ghost-particles-from-black-hole-jetstream-found-in-arctic-20180712-p4zr4t.html

NASA May Have Discovered and Then Destroyed Organics on Mars in 1976

 

NASA May Have Discovered and Then Destroyed Organics on Mars in 1976

Over 40 years ago, a NASA mission may have accidentally destroyed what would have been the first discovery of organic molecules on Mars, according to a report from New Scientist.

Source: www.space.com/41140-mars-lander-may-have-burned-organics.html

  NASA May Have Discovered and Then Destroyed Organics on Mars in 1976 Over 40 years ago, a NASA mission may have accidentally destroyed what would have been the first discovery of organic molecules on Mars, according to a report from New Scientist. Source: www.space.com/41140-mars-lander-may-have-burned-organics.html