New research from the Niels Bohr Institute, among others, shows that a young, newly formed star in the Milky Way had such an explosive growth, that it was initially about 100 times brighter than it is now. The results are published in the scientific journal, Astrophysical Journal Letters.
The picture shows the young protostar in the center surrounded by the gas and dust cloud. The red color shows the organic molecule, methanol, for which the radiation is concentrated close to the center. The blue color shows the HCO+ molecule with a clear extended ring-structure. The inner yellow ring is an indication where the temperature is 100 degrees above the absolute zero (-173 C) with the current luminosity of the star while the outer yellow ring shows where this temperature was reached when the star was a hundred times brighter.
Credit: (Credit: Jes Jørgensen (Niels Bohr Institute).
The young star was formed within the past 100,000 years in our own galaxy, the Milky Way. Using the large international telescope, the Atacama Large Millimeter Array (ALMA) in northern Chile, an international research team led by Jes Jørgensen from the Niels Bohr Institute studied the star and its surroundings.
"We studied the chemistry of the gas and dust cloud surrounding the early protostar (an early stage of star formation). In this dense cloud, a chemical reaction takes place that enables the formation of several kinds of complex molecules, including methanol. One would expect that all of the molecules would be near the star, but with one of them we saw a clear ring structure. Something had removed a certain molecule, HCO+, from a wide area around the protostar, explains astrophysicist Jes Jørgensen, Associate Professor at the Niels
Bohr Institute and the Centre for Star and Planet Formation at the University of Copenhagen, Denmark. He explains that what is special about the HCO+ molecule is that it is particularly sensitive to water vapour. Even small amounts of water vapour dissolve the molecule and the absence of HCO+ molecule can be used to discover what happened during the star formation process.
Violent eruption of light and heat
At first, the gas and dust cloud is extremely cold and simple molecules such as carbon monoxide and water settle on the grains of dust and solidify into ice. Here, where the molecules are close to each other, they bond together to form more complex molecules like methanol, ethanol, simple sugars, etc. and water in the form of ice. The gravity of the early protostar attracts much of the surrounding gas and dust cloud and when the material falls close to the young star, it slows down and the energy is converted into heat. This heat melts the ice, which turns into water vapour.
"From the area where the HCO+ molecule has been dissolved by water vapour we can now calculate how bright the young star has been. It turns out that that the area is much greater than expected compared to the star's current brightness. The protostar has been up 100 times brighter than the star is now. From the chemistry we can also say that this change happened within the last 100-1000 years – that is to say, very recently from an astronomical point of view," explains Jes Jørgensen.
Such an eruption of hot brightness can also explain the content of condensed methanol and the high content of molecules with carbon, as found in the gas cloud. This could also have a great influence on the chemical processes that lead to the formation of complex organic molecules that can later be incorporated into planetary systems. Jes Jørgensen believes that there has not only been a single burst of light and heat radiation, but that it could happen several times during the formation process.
"One of the major questions if we take a long view, is whether this is a common phenomenon – whether all young stars undergo similar 'eruptions' and if so, how often," wonders Jes Jørgensen, who as a scientist is always on the hunt to solve more of the mysteries of the universe.
For more information contact:
Jes Jørgensen, astrophysicist, Associate Professor at the Niels Bohr Institute and the Centre for Star and Planet Formation at the University of Copenhagen. +45 4250-9970, email@example.com
Gertie Skaarup | EurekAlert!
SF State astronomer searches for signs of life on Wolf 1061 exoplanet
20.01.2017 | San Francisco State University
Molecule flash mob
19.01.2017 | Technische Universität Wien
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences