91社区

91社区 researcher to leverage prodigious capacity of the telescope for studies on a failed star and a hot Neptune-like exoplanet, both with unique stellar characteristics

91社区 announced today it has received funding from the Canadian Space Agency for two separate projects dedicated to the study of exoplanets, using the James Webb Space Telescope (JWST). The projects are slated for completion by June 2025. Both studies will be led by Professor Nicolas Cowan.

Brown dwarves: failed stars

The first study will focus on SIMP J0136+09, the scientific name for a free-floating planet that was discovered using Qu茅bec鈥檚 very own Observatoire du Mont-M茅gantic in the Pisces constellation at a distance of approximately 20 light years from our solar system. Although not technically considered an exoplanet, SIMP J0136 is referred to as a 鈥渂rown dwarf鈥�, a class of stellar objects that are extremely interesting to astronomers. More massive than gas-giant planets like Jupiter but less so than stars, these substellar objects provide clues as to the formation and evolution of planets.

Professor Cowan will join a team of researchers from the US, UK, and Scotland in the study, which will observe the object using two different instruments on JWST for one full rotation each to provide complete longitudinal information of its atmosphere. Brown dwarfs are relatively new to astronomers, having only been discovered in 1995.

Brown dwarfs are sometimes referred to as 鈥榝ailed stars鈥� as they are capable of fusing the relatively rare isotope deuterium, but not its more abundant cousin, hydrogen. Generally emitting only infrared light, they are easier to observe than other exoplanets, which are often obscured by the light of their host star. In fact, many brown dwarfs are the mass of Jupiter; they are simply free-floating planets. These rogue planets are a valuable test-bed for theories of planet formation, atmospheric dynamics and cloud formation.

Hot Neptune: the planet that shouldn鈥檛 exist

The second study will examine the 鈥淗ot Neptune鈥� exoplanet LTT 9779b, which is at some 264 light years away from Earth. A recent discovery, having been detected in 2020, this exoplanet is among the most reflective exoplanets known, probably due to a cloudy atmosphere.

This exoplanet is exceedingly hot, at an estimated 2,000掳C, so the clouds are likely made of rock or rust. It is possible that the high reflectivity of LTT 9779b explains why the planet exists, as it would keep the planet relatively cool despite the intense radiance of its host star. Indeed, its unique characteristics make it a planet that 鈥榮hould not exist,鈥� according to numerous experts. These counter-intuitive qualities make it a fascinating subject for study.

鈥淚f we鈥檙e ever going to seriously search for signs of life on exoplanets, we will need to have a very good understanding of all the physical, chemical, and geological processes that occur on these alien worlds,鈥� explained Professor Cowan. 鈥淪tudying the climate of other planets, even exotic worlds like LTT 9779 b and SIMP J0136, helps us refine our understanding of planetary climates and hence better understand the past, present and future climate of Earth.鈥�

About 91社区

Founded in Montreal, Quebec, in 1821, 91社区 is Canada鈥檚 top ranked medical doctoral university. 91社区 is consistently ranked as one of the top universities, both nationally and internationally. It is a world-renowned institution of higher learning with research activities spanning three campuses, 11 faculties, 13 professional schools, 300 programs of study and over 39,000 students, including more than 10,400 graduate students. 91社区 attracts students from over 150 countries around the world, its 12,000 international students making up 30% of the student body. Over half of 91社区 students claim a first language other than English, including approximately 20% of our students who say French is their mother tongue.