iREx researchers awarded coveted JWST time during Cycle 2

Approximately 5,000 hours of observing time have been awarded for the James Webb Space Telescope’s (JWST) second year of observations, also known as Cycle 2, for its General Observers (GO) programs.

Many Canadian astronomers were selected to lead observing programs during Cycle 2 covering a wide range of research interests, for a total of 206 hours of observing time on programs led by Principal Investigators (PIs) at Canadian institutions. Nearly half of these hours will be on three programs led by iREx researchers, including 82 hours for a Large Program led by Prof. Björn Benneke. This is the largest single GO program led by a Canadian astronomer during Cycle 2. An additional observing program will be co-led by iREx Postdoctoral Researcher, Jake Taylor, as co-PI.

Find out more about iREx researchers’ Cycle 2 JWST programs here:

Jake Taylor, Postdoctoral Researcher at iREx and Oxford University.

Program 3818: To be or not to be in equilibrium: Probing disequilibrium chemistry on the warm sub-Neptune TOI-270 d
PI: Cyril Gapp (MPIA)
Co-PIs: Luis Welbanks (Arizona State), Dana Louie (NASA GSFC), Jake Taylor (iREx/Oxford), Thomas Mikal-Evans (MPIA)
Time awarded: 7.23h using NIRSpec/BOTS
Summary: Mini Neptunes, exoplanets with sizes between that of Earth’s and Neptune, are the most commonly detected exoplanet, yet astronomers have found none in our own Solar System. This program proposes to observes the mini Neptune TOI-270 d and study its atmosphere using the technique of transmission spectroscopy. This target will already be observed using the Canadian NIRISS instrument for the NEAT Guaranteed Time Observations (GTO) program led by Prof. David Lafrenière (iREx). This GO proposal would acquire additional data from the NIRSpec instrument, allowing for the detection of carbon monoxyde and methane and a better understanding of the balance of different molecules in exoplanet atmospheres.
N.B.: Since being selected, this program has been withdraw from the observing cycle.

Program 4082: Putting it all Together: Dynamics and Chemistry Probed Through Transmission Spectroscopy of a Cloud-Free Exoplanet
PI: Michael Radica (iREx/UdeM)
co-PI: Jake Taylor (iREx/Oxford)
Time awarded: 6.69h using NIRSpec/BOTS
Summary: JWST’s first exoplanet atmospheric spectrum, revealed in July 2022 along with the reveal of JWST’s first images, was of the Hot Jupiter WASP-96 b using the NIRISS instrument. Previous Hubble observations indicated the surprising absence of clouds. Initial JWST observations confirmed the presence of water vapor, but also provided evidence for clouds and hazes, contradicting Hubble’s findings. More recent analyses of the JWST data led by iREx researchers (Radica et al. 2023, Taylor et al. 2023) have confirmed WASP-96 b to be a gas giant planet with a rare cloud-free atmosphere. This proposal will collect additional transmission spectroscopy data to obtain a more robust atmospheric composition of this planet that would take into consideration complicated physical and chemical processes at play.

Björn Benneke, Professor at iREx.

Program 4098: Exploring the existence and diversity of volatile-rich water worlds
PI: Björn Benneke (iREx/UdeM)
co-PI: Thomas Mikal-Evans (MPIA)
Time awarded: 82h using NIRISS/SOSS and NIRSpec/BOTS
Summary: This proposed program will conduct a targeted search for a new class of planets called “water worlds”, which would be rocky cores completely covered in a thick layer of water. iREx researchers have already been involved in the discovery of a few of these potential water worlds, such as TOI-1452 b and Kepler-138 d. This new JWST program will obtain atmospheric transmission spectra of five of the most promising water-world candidates, which will help scientists better understand the nature of this mysterious type of exoplanet.

Pierre-Alexis Roy, Ph.D. student at iREx.

Program 4102: Hydrogen-rich sub-Neptune or exposed Neptune mantle? Confirming the nature of the most favorable sub-Neptune for JWST emission spectroscopy
PI: Pierre-Alexis Roy (iREx/UdeM)
Co-PI: Björn Benneke (iREx/UdeM)
Time awarded: 13.38h using NIRSpec/BOTS
Summary: This proposed program will also seek to better understand the most common type of exoplanet: mini Neptunes. Despite being detected and observed for many year, it is still unclear how mini Neptunes form and whether they could lose their hydrogen-rich envelope to eventually become super Earths. The exoplanet TOI-824 b, a hot mini Neptune, could potentially be in this theorized transition stage. This program will obtain emission spectroscopy from TOI-824 b, which means that JWST will be able to observe the light of the exoplanet itself during two eclipse observations.

Many more JWST Cycle 2 GO programs will be supported by Canadian and iREx researchers as co-Investigators. To see all selected Cycle GO programs, consult the STScI website.

The competition was quite ferocious this year, we over seven times more observing hours requests than could be awarded. This pressure factor (known as an oversubscription in astronomy) has nearly doubled from a factor four during Cycle 1. Congratulations to all astronomers with awarded time, as well as all astronomers who submitted proposals! The world cannot wait to see what more amazing scientific discoveries await us thanks to the JWST and the scientists making use of its data.

The next Call for Proposals for JWST’s Cycle 3 GO Programs is expected at the end of Summer 2023 with a submission deadline on October 27, 2023.