Showing posts with label Dark matter. Show all posts
Showing posts with label Dark matter. Show all posts
Hayabusa probe 2: What Japan expects from its fragments of the asteroid Ryugu

Hayabusa probe 2: What Japan expects from its fragments of the asteroid Ryugu

Hayabusa probe 2: What Japan expects from its fragments of the asteroid Ryugu





Next week, the Japanese Space Agency will open the capsule containing rock fragments taken from the asteroid Ryugu and brought back to Earth on December 5. These samples should provide information on the origin of the Solar System and life on Earth.



The eyes of astrophysicists around the world are on the city of Sagamihara, south of Tokyo, home to a research center of the Japan Aerospace Exploration Agency (Jaxa). It is in this imposing white building that the very valuable samples taken from the asteroid Ryugu, which arrived from Australia on December 8, would be kept. A capsule believed to contain these potentially information-rich rock fragments was dropped in a desert area of southern Australia six days ago by the Japanese Hayabusa 2 probe.


The Agency will open the capsule next weekend to officially confirm the success of the operation, ITmedia Newsreported. In fact, anxious not to damage the famous samples by exposing them to air, the scientists took care to first transport the capsule to Japan, in order to open it in the ultravide.


At this point, no one is in a position to know if they have actually been able to recover asteroid fragments. A gas has been collected, but it is too early to say whether or not it comes from these fragments. Nevertheless, Hayabusa 2's mission itself is already a success. Makoto Yoshikawa of JAXA, whose remarks are reported by ITmedia News, said at the press conference held on 8 December:


"I'm so reassured that the capsule has come back to us. We still have to know."



Source:- Flash News and News Agencies

Scientists confounded by new findings on universe's mysterious dark matter | Flash News

Scientists confounded by new findings on universe's mysterious dark matter | Flash News

Scientists confounded by new findings on universe's mysterious dark matter





Dark matter, a mysterious invisible substance that makes up most of the mass of galaxies, including our own Milky Way, is again confusing scientists, with new observations of distant galaxies in conflict with current understanding of its nature.



Research published this week revealed an unexpected discrepancy between observations of dark matter concentrations in three massive galaxy clusters encompassing trillions of stars and theoretical computer simulations of how dark matter should be distributed.



"Either there is an ingredient missing in the simulations or we have made a fundamentally incorrect assumption about the nature of dark matter," astrophysicist Priyamvada Natarajan, co-author of the study published in the journal Science, said on Friday.



Dark matter is the invisible glue that holds stars together inside a galaxy.  It also creates invisible scaffolding that allows galaxies to form clusters.  But it has very specific properties.  It does not emit, absorb or reflect light and does not interact with any known particles.




It is thought that most of the matter in the universe, around 96%, is dark matter, with ordinary matter - the visible substance that makes up stars, planets, and people - just 4%.



The presence of dark matter is only known by its gravitational attraction on visible matter in space.  It differs from the equally enigmatic and invisible dark energy, which is regarded as a property of space and which is at the origin of the accelerated expansion of the universe.  Dark energy is disgusting.  Dark matter attracts by gravity.



The new study involved observations from the Hubble Space Telescope and the European Southern Observatory's Very Large Telescope in Chile.



When light from distant sources such as distant galaxies passes through matter such as another galaxy or a cluster of them, the light is deflected and bent - a phenomenon called a "gravitational lens," said the  astrophysicist and lead author of the study Massimo Meneghetti from the Observatory of Astrophysics and Space Science in Bologna and National Institute of Astrophysics in Italy.



The new observations showed that the gravitational lensing effects produced by galaxies residing inside huge galaxy clusters were much stronger than the current dark matter theory envisioned, suggesting a surprisingly high concentration of dark matter in these galaxies.


 “It's quite surprising,” Meneghetti said.






Source:- Flash News and News Agencies