Wednesday, July 18, 2018

Twelve New Moons Discovered Orbiting Around Jupiter

 A team led by astronomers from Carnegie Institution for Science have discovered twelve new moons orbiting Jupiter. This brings the total number of known moons around Jupiter to 79.
 Nine of the new moons revolve around Jupiter in a distant retrograde orbit, moving in the opposite direction of Jupiter's spin rotation. They are believed to be the remnants of three once-larger parent bodies that broke apart during collisions with asteroids, comets or other moons. The two other moons revolve around Jupiter in a closer, regular orbit. As they have similar orbital distance and angles of inclinations around Jupiter, they are thought to be fragments of a larger moon that broke apart.
 The final moon is Jupiter's smallest known moon, being less than one kilometre in diameter. Orbiting farther from Jupiter than the two inner moons, this moon orbits prograde (in the direction of Jupiter's spin) and crosses the outer retrograde moons. As a result, head-on collisions are much more likely to occur between this oddball moon and the retrograde moons.
 It is believed that this smaller prograde moon could be the last visible remnant of a once-larger prograde-orbiting moon that formed some of the retrograde moons visible today during past head-on collisions.
 The new moons were first seen in March of last year from the Cerro Tololo Inter-American Observatory in Chile, but it took more than a year to confirm that the bodies were indeed locked in orbit around the planet.
  “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  Scott S. Sheppard, the team lead at Carnegie.

Read the full press release at: https://carnegiescience.edu/node/2367
Or view the full reports here: https://minorplanetcenter.net/mpec/RecentMPECs.html

Image Credit: Carnegie Institution for Science

Tuesday, July 17, 2018

Rate of the Expansion of the Universe Measured with Greatest Precision Yet

 According to a new study published by astronomers using the NASA/ESA Hubble Space Telescope and ESA's Gaia Space Observatory, the rate of the expansion of the Universe has been made through the most precise calculations to date. The study provides further evidence of the discrepancy between the expansion rate of the nearby Universe and the distant, primeval Universe.
 Through this study, the uncertainty of the expansion of the universe has been reduced to an uncertainty of just 2.2%. This rate was found to be about 73.5 km (45.6 miles) per second per megaparsec through data collected from the nearby Universe. In other words, for every 3.3 million light-years farther away a galaxy is from us, it appears to be moving 73.5 kilometres per second faster.
 Yet data from another mission, ESA's Planck mission, predicts that the Universe should be expanding today at a slower 67 km (41.6 miles) per second per megaparsec. This older study was based on the mapping of the primeval Universe as it appeared only 360,000 years after the Big Bang.
 This discrepancy suggests that there could be new physics behind the foundations of the Universe. This could partly be influenced by the interaction strength of dark matter, dark energy being even more exotic than previously thought, or an unknown new particle in the space.

Read more about this fascinating story at: http://www.sci-news.com/astronomy/universes-expansion-hubble-gaia-06205.html
Or read the full study at: http://iopscience.iop.org/article/10.3847/1538-4357/aac82e

Saturday, July 14, 2018

Photo of the Week

 This week for Photo of the Week, we would like to feature a serene shot of the Milky Way and the Magellanic Clouds. Taken in Egmont National Park in New Zealand by the talented photographer Cortland McCullum, the peak of Mt. Taranaki can be seen in the foreground, silhouetted by the beautiful star-filled sky and the majestic Milky Way. On this night, it was a little chilly, worthy of a few layers of clothing and a warm blanket. But as the Milky Way rose above the horizon, all that cool air disappeared as the starry sky filled the night, beautiful in all of its glory.
 For more fantastic photos, be sure to check out McCullum's Instagram @cortland_mc at https://www.instagram.com/cortland_mc/

Friday, July 13, 2018

Neutrino Detection Suggests Blazar as Cosmic Ray Source

 According to new papers released by researchers using the National Science Foundation's (NSF) Icecube detector at the South Pole, evidence suggests that a blazar is the source of high-energy neutrinos. This blazar, a giant elliptical galaxy with a massive spinning black hole at its core, was first singled out by a neutrino alert on September 22, 2017.
 Cosmic neutrinos are ghostly subatomic particles that are capable of travelling unhindered for billions of lights years from the most extreme environments in the universe to Earth. On the other hand, cosmic rays are highly energetic charged particles. Their paths are difficult to trace back to their source because the powerful magnetic fields that fill space warp their trajectories. Yet the source of these rays also produce neutrinos.
  “The evidence for the observation of the first known source of high-energy neutrinos and cosmic rays is compelling,” said Francis Halzen, a University of Wisconsin–Madison professor of physics and the lead scientist for the IceCube Neutrino Observatory.
 When the neutrino alert was sent out on September 22, telescopes worldwide were on high alert for follow-u observatories. From telescopes such as NASA"s Fermi Gamma-ray Space Telescope to the Major Atmospheric Gamma Imaging Cherenknov Telescope in the Canary Islands, a flare of high0energy gamma rays was detected originating from the blazar, implicating the galaxy as the most likely source.
"Fermi was the first telescope to identify enhanced gamma-ray activity from TXS 0506+056 within 0.06 degrees of the IceCube neutrino direction," stated the press released from IceCube. "In a decade of Fermi observations of this source, this was the strongest flare in gamma rays, the highest-energy photons. A later follow-up by MAGIC detected gamma rays of even higher energies."
“Fermi has been monitoring some 2,000 blazars for a decade, which is how we were able to identify this blazar as the neutrino source,” said Regina Caputo, the analysis coordinator for the Fermi Large Area Telescope collaboration. “High-energy gamma rays can be produced either by accelerated electrons or protons. The observation of a neutrino, which is a hallmark of proton interactions, is the first definitive evidence of proton acceleration by black holes.”

Read the full press releases at:
https://icecube.wisc.edu/news/view/586
https://nsf.gov/news/news_summ.jsp?cntn_id=295955

Or read the full studies at:
http://science.sciencemag.org/content/361/6398/eaat1378
http://science.sciencemag.org/content/361/6398/147

Or watch the press conference here: https://www.youtube.com/watch?v=iChBhHpFtMI

Image: Artist's impression of neutrino interacting in the NSF's IceCube detector via Nicolle R. Fuller/NSF/IceCube





Thursday, July 12, 2018

Plasma Waves Discovered Moving Between Saturn, Enceladus - Hear Them Now

 According to new research based on data collected from NASA's Cassini spacecraft's Grand Finale orbits, a powerful and dynamic interaction of plasma waves was discovered to be occurring between Saturn, through its rings, to its moon Enceladus.
 These waves were found to be travelling on magnetic field lines connecting Saturn with Enceladus, allowing for energy to flow back and forth between the two bodies. Similarly like air and water, plasma (the fourth state of matter) generates waves to carry energy.
 Researchers converted the recording of plasma waves into an audio file that could be heard - similar in how a radio converts electromagnetic waves into music.
  “Enceladus is this little generator going around Saturn, and we know it is a continuous source of energy,” said Ali Sulaiman, planetary scientist at the University of Iowa, Iowa City, and a member of the RPWS team. “Now we find that Saturn responds by launching signals in the form of plasma waves, through the circuit of magnetic field lines connecting it to Enceladus hundreds of thousands of miles away.”


Read the full press release at: https://www.nasa.gov/feature/jpl/listen-sound-of-electromagnetic-energy-moving-between-saturn-enceladus

Wednesday, July 11, 2018

'Sausage' Galaxy Collided with Milky Way 8-10 Billion Years Ago

 According to a new study published by a team of British astronomers, an unknown dwarf galaxy dubbed the 'Sausage' galaxy collided with the Milky Way Galaxy around 8 to 10 billion years ago. This collision left the dwarf galaxy in shreds, leaving behind a wreckage of stars still visible today.
 Unlike other collisions such as the Milky Way's ongoing collision with the Sagittarius dwarf galaxy, the Sausage galaxy was much more massive. Totalling more than 10 billion times the mass of our Sun, the collision left the Milky Way's disk either puffed up or completely fractured following the impact. As for the dwarf galaxy, its detritus would have been scattered across the inner parts of the Milky Way, contributing to the bright centre of the Milky Way galaxy and its surrounding 'stellar halo'.
 “Evidence of this galactic remodeling is seen in the paths of stars inherited from the dwarf galaxy. The Sausage stars are all turning around at about the same distance from the center of the Galaxy,” said Dr. Alis Deason, from Durham University. “These U-turns cause the density in the Milky Way’s stellar halo to decrease dramatically where the stars flip directions.”

Read more about this fascinating story at: http://www.sci-news.com/astronomy/sausage-galaxy-milky-way-collision-06167.html
Or read the studies at the Monthly Notices of the Royal Astronomical Society and the Astrophysical Journal Letters.

Image: Artists impression of the collision between the Sausage Galaxy and the Milky Way Galaxy. Credits: V. Belokurov / Juan Carlos Muñoz / ESO.

Tuesday, July 10, 2018

NASA's Kepler Space Telescope Enters Hibernation Mode

 NASA's Kepler space telescope has officially entered into its low-fuel hibernation state. According to state officials, the telescope which is famous for discovering over 2,500 exoplanets known to date is nearing the end of its life.
 In a move to attempt to ensure that Kepler is able to beam its latest data haul back to its scientist handlers next month, NASA scientists are putting it into hibernation to ensure it has enough fuel for its last haul.
  "To bring the data home, the spacecraft must point its large antenna back to Earth and transmit the data during its allotted Deep Space Network time, which is scheduled in early August," NASA officials wrote in a statement on July 6. (The Deep Space Network is the global array of radio telescopes that NASA uses to communicate with its spacecrafts.)
 "Until then, the spacecraft will remain stable and parked in a no-fuel-use safe mode," added the team. "On August 2, the team will command the spacecraft to awaken from its no-fuel-use state and manoeuvre the spacecraft to the correct orientation and downlink the data. If the manoeuvre and download are successful, the team will begin its 19th observation campaign on August 6 with the remaining fuel.

Read the full press release at: https://www.nasa.gov/feature/ames/nasa-s-kepler-spacecraft-pauses-science-observations-to-download-science-data