Have Astronomers Seen a Forming Planet in Action?

Monday, September 29, 2014

Have Astronomers Seen a Forming Planet in Action?

Have Astronomers Seen a Forming Planet in Action?:

Image at 7 mm wavelength of the dusty disk around the star HD 169142 obtained with the Very Large Array (VLA) at 7 mm wavelength. The positions of the protoplanet candidates are marked with plus signs (+) (Osorio et al. 2014, ApJ, 791, L36). The insert in the upper right corner shows, at the same scale, the bright infrared source in the inner disk cavity, as observed with the Very Large Telescope (VLT) at 3.8 micron wavelength (Reggiani et al. 2014, ApJ, 792, L23).

Image of the dusty disk around the star HD 169142 obtained with the Very Large Array. The positions of the protoplanet candidates are marked with plus signs (Osorio et al. 2014, ApJ, 791, L36). The insert in the upper right corner shows the bright infrared source in the inner gap, as observed with the Very Large Telescope. (Reggiani et al. 2014, ApJ, 792, L23).

Huge disks of dust and gas encircle many young stars. Some contain circular gaps — likely the result of forming planets carving out cavities along their orbital paths — that make the disks look more like ripples in a pond than flat pancakes.

But astronomers know only a few examples, including the archetypal disk surrounding Beta Pictoris, of this transitional stage between the original disk and the young planetary system. And they have never spotted a forming planet.

Two independent research teams think they’ve observed precisely this around the star HD 169142, a young star with a disk that extends up to 250 astronomical units (AU), roughly six times greater than the average distance from the Sun to Pluto.

Mayra Osorio from the Institute of Astrophysics of Andalusia in Spain and colleagues first explored HD 169142’s disk with the Very Large Array (VLA) in New Mexico. The 27 radio dishes configured in a Y-shape allowed the team to detect centimeter-sized dust grains. Then combining their results with infrared data, which traces the presence of microscopic dust, the group was able to see two gaps in the disk.

One gap is located between 0.7 and 20 AU, and the second larger gap is located between 30 and 70 AU. In our Solar System the first would begin at the orbit of Venus and end at the orbit of Uranus, while the second would begin at the orbit of Neptune, pass Pluto’s orbit, and extend beyond.

“This structure already suggested that the disk was being modified by two planets or sub-stellar objects, but, additionally, the radio data reveal the existence of a clump of material within the external gap, located approximately at the distance of Neptune’s orbit, which points to the existence of a forming planet,” said Mayra Osorio in a news release.

Maddalena Reggiani from the Institute for Astronomy in Zurich and colleagues then tried to search for infrared sources in the gaps using the Very Large Telescope. They found a bright signal in the inner gap, which likely corresponds to a forming planet or a young brown dwarf, an object that isn’t massive enough to kick start nuclear fusion.

The team was unable to confirm an object in the second gap, likely due to technical limitations. Any object with a mass less than 18 times Jupiter’s mass will remain hidden in the data.

Future observations will shed more light on the exotic system, hopefully allowing astronomers to better understand how planets first form around young stars.

Both papers have been published in the Astrophysical Journal Letters.

Tagged as: exoplanets, Planetary Disks, protoplanets, Very Large Array, Very Large Telescope

FASHION WEEK - USA Fashion and Music News
GOOGLE NEWS - Google News Blogger
PINTEREST ACROSS THE UNIVERSE - Google Images Nasa Images
LAST FM - Download Music Legally Direct From Artist
WOMEN COMMUNITY - Women Communty Photography Videos Beauty
DISNEY CHANNEL - Photos and Music News
BABY JUSTIN BIEBER - Google Images Google News
LADY GAGA - Google Images Google News
ACROSS THE UNIVERSE - Google Images Universe Pictures
VICTORIA´S SECRET COMMUNITY - Victoria´s Secret Fashion Show Photos

No comments:

Post a Comment

NASA Photos Photography

The National Aeronautics and Space Administration (NASA) is the United States government agency responsible for the civilian space program as well as aeronautics and aerospace research. President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA's predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

UFO SIGHTINGS PHOTO PHOTOGRAPHY

The Oxford English Dictionary defines a UFO as "An unidentified flying object; a 'flying saucer'." The first published book to use the word was authored by Donald E. Keyhoe. The acronym "UFO" was coined by Captain Edward J. Ruppelt, who headed Project Blue Book, then the USAF's official investigation of UFOs. He wrote, "Obviously the term 'flying saucer' is misleading when applied to objects of every conceivable shape and performance. For this reason the military prefers the more general, if less colorful, name: unidentified flying objects. UFO (pronounced Yoo-foe) for short." Other phrases that were used officially and that predate the UFO acronym include "flying flapjack", "flying disc", "unexplained flying discs", "unidentifiable object", and "flying saucer". The phrase "flying saucer" had gained widespread attention after the summer of 1947. On June 24, a civilian pilot named Kenneth Arnold reported seeing nine objects flying in formation near Mount Rainier. Arnold timed the sighting and estimated the speed of discs to be over 1,200 mph (1,931 km/h). At the time, he described the objects' shape as being somewhat disc-like or saucer-like, leading to newspaper accounts of "flying saucers" and "flying discs". In popular usage the term UFO came to be used to refer to claims of alien spacecraft. and because of the public and media ridicule associated with the topic, some investigators prefer to use such terms as unidentified aerial phenomenon (or UAP) or anomalous phenomena, as in the title of the National Aviation Reporting Center on Anomalous Phenomena (NARCAP).

UFO PHOTO PHOTOGRAPHY

UFO - Unidentified Flying Object An unidentified flying object, or UFO, in its most general definition, is any apparent anomaly in the sky that is not identifiable as a known object or phenomenon. Culturally, UFOs are associated with claims of visitation by extraterrestrial life or government-related conspiracy theories, and have become popular subjects in fiction. While UFOs are often later identified, sometimes identification may not be possible owing to the usually low quality of evidence related to UFO sightings (generally anecdotal evidence and eyewitness accounts). Stories of fantastical celestial apparitions have been told since antiquity, but the term "UFO" (or "UFOB") was officially created in 1953 by the United States Air Force (USAF) to serve as a catch-all for all such reports. In its initial definition, the USAF stated that a "UFOB" was "any airborne object which by performance, aerodynamic characteristics, or unusual features, does not conform to any presently known aircraft or missile type, or which cannot be positively identified as a familiar object." Accordingly, the term was initially restricted to that fraction of cases which remained unidentified after investigation, as the USAF was interested in potential national security reasons and/or "technical aspects" (see Air Force Regulation 200-2). During the late 1940s and through the 1950s, UFOs were often referred to popularly as "flying saucers" or "flying discs". The term UFO became more widespread during the 1950s, at first in technical literature, but later in popular use. UFOs garnered considerable interest during the Cold War, an era associated with a heightened concern for national security. Various studies have concluded that the phenomenon does not represent a threat to national security nor does it contain anything worthy of scientific pursuit (e.g., 1951 Flying Saucer Working Party, 1953 CIA Robertson Panel, USAF Project Blue Book, Condon Committee).

Photos of Nature | Nature Photography What is The Universe

Photos of Nature | Nature Photography What is The Universe

Monday, September 29, 2014