14 DAY TRIAL // Scientists at the University of Notre Dame, in Indiana, reveal in a new study that they were recently able to photograph one of the rarest types of brown dwarfs, which are objects heavier than gas giant-class planets, but smaller than regular stars.
Unlike conventional stars, brown dwarfs are not fully formed, in the sense that they are not able to support nuclear fusion at their cores. They do tend to be hotter than gas giants, but act as plants at the same time. They lie in a sort of gray area, which astronomers known very little about.
The fact that the UND group, led by the Freimann assistant professor of physics Justin R. Crepp, was able to photograph such an object directly should prove very useful in boosting our understanding of this entire class of cosmic features. The study is detailed in a recent issue of the Astrophysical Journal.
The first indications that a brown dwarfs exists at the target location were found by the TRENDS (TaRgetting bENchmark-objects with Doppler Spectroscopy) high-contrast imaging survey, which is being conducted at the W. M. Keck Observatory, on Mauna Kea, Hawaii.
Additional data were collected using the High Resolution Echelle Spectrometer (HIRES) instrument on the 10-meter (33-foot) Keck I Telescope. The object in question is designated HD 19467 B, and was cataloged as a T-dwarf, meaning it is around 100,000 times dimmer than its parent star.
Due to the fact that the distance between Earth and this object is known with great precision, experts were able to use this data to refine their estimates of the planet's mass, age, orbit, and chemical composition. These information was obtained without analyzing light spectra from this alien world.
“This object is old and cold and will ultimately garner much attention as one of the most well-studied and scrutinized brown dwarfs detected to date. With continued follow-up observations, we can use it as a laboratory to test theoretical atmospheric models,” Crepp explains.
“Eventually we want to directly image and acquire the spectrum of Earth-like planets. Then, from the spectrum, we should be able to tell what the planet is made out of, what its mass is, radius, age, etc., basically all relevant physical properties,” the team leader goes on to say.