Birth Of A Planet: Astronomers Detect Star's Dust Cloud Give Birth To Icy Giant World
Astronomers have spotted a possible birth of a new planet from a nearby young star named TW Hydrae. The baby world might just have started to grow, but it has already become one ice giant whose size is possibly a bit larger than that of Neptune.
A team of researchers in Japan had been using the Atacama Larger Millimeter/submilliliter Array (ALMA) to observe the TW Hydrae. Led by Takashi Tsukagoshi of Ibaraki University, the team observed the young star to gain more knowledge about the formation of planets with the help of Atacama Large Millimeter Array (ALMA).
ALMA, which consists of 66 radio antennae, has the ability to peer into the star system with astonishing accuracy. Using the observations, astronomers are able to use it as a kind of proto-planetary experimental object because of its close proximity (only 175 light-years) to Earth and also its unexpected orientation. The star's proto-planetary disk is almost perfectly facing Earth, allowing astronomers to study the planetary birth in action.
By taking into consideration, two separate wavelengths of radio frequency emissions from the warm dust present in the TW Hydrae disk, dust particles of different sizes can be studied. According to the theoretical models, the dark rings rooted inside the bright disk should be containing smaller dust particles than the particles in the rest of the disk in case a baby exo-planet is present.
TW Hydrae, researchers believe, is perfect to study about how icy giant planets such as Uranus and Neptune were earlier formed. The young star is only 10 million years old and its axis points to Earth, giving us a clear view of every step of the possible planetary formation.
Previous studies about TW Hydrae have shown that the young star is still surrounded by a disk of dust grains, for which the disk is the formation site, states Space.com. Based on the observations of ALMA, the disk does have multiple gaps. Smaller dust grains appear in the gap of the disk while bigger dust grains could not be found. Hence, the question arises about why the dust grains are distributed this way.
New models suggest that the behavior of the dust grains is due to their gravitational interaction with the giant planet, states a UPI report. Researchers have predicted that the gaps found in the disk are produced due to presence of massive planets. The gravitational force and friction that exists between gas and dust grains pushes the bigger dust grains out of the disk while the smaller dust grains remain in the gap, Science Daily reports.
Meanwhile, the researchers have also determined the massiveness of the baby planet by analyzing the distribution of dust grains in the stellar system. "Combining the orbit size with the brightness of the TW Hydrae, the planet could be an icy giant planet just like Neptune," stated Tsukagoshi.