Categories: world

Unknown treasure chest of planets hiding in dust – ScienceDaily

"Super-Earths" and Neptune-sized planets could be formed around young stars in much greater numbers than researchers thought, showing new research…

“Super-Earths” and Neptune-sized planets could be formed around young stars in much greater numbers than researchers thought, showing new research by an international team of astronomers.

Observation of a selection of young stars in a star forms the region of the constellation Taurus, researchers found that many of them would be surrounded by structures that could best be explained as traces created by invisible, young planets in the production. The research, published in the Astrophysical Journal helps researchers better understand how our own solar system came.

Some 4.6 billion years ago our solar system was a fun, swelling swirl of gas and dust around our newborn sun. In the early stages, the so-called protoplanetic disc had no distinguishable characteristics, but soon parts of it began to accumulate in lumps of matter &#821

1; future planets. When they picked up new material along their journey around the sun, they grew and began to plow patterns of slots and rings in the disc that they formed. Over time, the dusty disc became the relatively arranged arrangement we know today, consisting of planets, moons, asteroids and occasional comets.

Researchers are building this scenario on how our solar system came upon observations of protoplanetary discs around other stars that are young enough to be currently in the process of born planets. Using the Atacama Large Millimeter Array, or ALMA, which consisted of 45 radio antennas in the Chilean Atacama desert, the team conducted a survey of young stars in the Taurus starring region, a large cloud of gas and dust locating a modest 450 light years from Earth. When the researchers depicted 32 stars surrounded by protoplanetary discs, they found that 12 of them – 40 percent – have rings and gaps, structures that, according to the team’s measurements and calculations, can best be explained by the presence of nascent planets. [19659003] “This is fascinating because it is the first time exoplanet statistics suggest that the super-earth and neptune are the most common type of planets, coinciding with observations of protoplanetary disks,” said the paper’s author, Feng Long, a doctoral student at Kavli- Institute for Astronomy and Astrophysics at Beijing University in Bejing, China.

While some protoplanetic dishes appear as uniform, pancake-like objects lack any characteristics or patterns, concentric bright rings apart from gaps have been observed but earlier surveys have focused on the brightest of these objects because they are easier to find, it was unclear how common dishes with ring and gap structures are really in his universe. This study presents the results of the first object survey by selecting the target discs independently of their brightness – in other words, the researchers did not know if any of their goals had ring structures when they selected them for the survey. [19659003] “Most previous observations had been aimed at detecting the presence of very massive planets, which we know are rare, which had cut out large internal holes or slots in light disks,” said the other author of the paper Paola Pinilla, a NASA Hubble- fellow at the University of Arizona’s Steward Observatory. “While massive planets had expired in some of these candles, a little had been known about the tougher dishes.”

The team, which also includes Nathan Hendler and Ilaria Pascucci at UA’s Lunar and Planetary Laboratory, measured the properties of rings and gaps observed with ALMA and analyzed data to evaluate possible mechanisms that could cause the observed rings and gaps. Although these structures can be cut by planets, previous research has suggested that they can also be created by other effects. In a generally proposed scenario, so-called ice lines cause changes in dust chemistry across the disc in response to the distance to the host star and its magnetic fields create pressure variations across the disc. These effects can create variations in the disc, manifest as rings and gaps.

The researchers conducted analyzes to test these alternative explanations and could not establish any relationship between star features and patterns of gaps and rings that they observed.

We can therefore rule out the widely proposed idea of ​​ice lines that cause the rings and gaps, “said Pinilla. “Our thinking leaves growing planets as the most likely reason for the patterns we observed, although some other processes may also be at work.”

Because it is impossible to detect the individual planets, it is impossible because of the overwhelming brightness of the host star. The team performed calculations to get an idea of ​​what planets can be formed in the Taurus constellation region. According to the results, Neptune-sized gas planets or so-called super-earth planets of up to 20 earthmasses should be the most common. Only two of the recorded discs could potentially end behemoth’s rivaling Jupiter, the largest planet in the solar system.

“Since most exoplanet surveys can not penetrate the thick dust of the protoplanetary disk, all exoplanets, with an exception, have been discovered in more developed systems where a disc is no longer present,” said Pinilla.

The research group plans to move ALMAs antennas farther apart, which would increase the resolution to about five astronomical units (an AU equals the average distance between the ground and the sun) and to make antennas sensitive to other frequencies sensitive to other types of dust.

“Our results is an exciting step to understand this key phase of planetary formation, “In short,” and by making these adjustments, we hope to better understand the origins of the rings and gaps. “

Share
Published by
Faela