Protoplanetary Disk Archives

NH3-H2O co-deposition experiments. All experiments have been performed on a gold substrate. The TPDs have a ramp of 0.2K/s. The solid lines represent the desorption of NH3 while the dashed-dotted lines represent the desorption of water. Lines of the same colour belong to the same set of experiments. Inset: TPD of NH3 from a gold surface used to calibrate all the consequent experiments. -- astro-ph.SR

Astrochemistry, Astrogeology, Biochemistry & Organic Chemistry, Comets and Asteroids, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Interstellar, Status Report

Experimental Study Of The Binding Energy Of NH3 On Different Types Of Ice And Its Impact On The Snow Line Of NH3 And H2O

by Keith CowingDecember 3, 2023December 2, 2023

N-bearing molecules (like N2H+ or NH3) are excellent tracers of high-density, low-temperature regions like dense cloud cores and could shed light into snowlines in protoplanetary disks and the chemical evolution […]

A summary of planet properties at the onset of XUV photoevaporation from models in Figure 6 with constant equilibrium temperatures of 600K, 900K, 1200K, and 1500K in blue, green, orange and red respectively. We assume the disc disperses at 𝑡disp = 3 × 106 yrs with a disc dispersal timescale of 𝜏disp = 105 yrs, all of which lead to XUV photoevaporation dominating at ∼ 4 Myrs, which coincides with the local protoplanetary disc having completely dispersed in these models. The left-hand panel shows the atmospheric mass fraction. Green lines with squares represent results from Owen & Wu (2016), for which boil-off was performed at 900K with initial atmospheric mass fractions of 0.3 and 0.1 in dot-dashed and dotted lines, respectively (note that initial atmospheric mass fractions in our models are calculated self-consistently through gaseous accretion). The right-hand panel shows planet sizes, including those that have been stripped of their atmosphere (atmospheric mass fraction < 10−4 ) and sit on an Earth-like composition line (grey dashed). This panel can be interpreted as a primordial mass-radius distribution. -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Gaia - Planetary Perspectives, Habitable Zones, Status Report

Under The Light Of A New Star: Evolution Of Planetary Atmospheres Through Protoplanetary Disc Dispersal And Boil-off

by Keith CowingNovember 22, 2023November 22, 2023

The atmospheres of small, close-in exoplanets are vulnerable to rapid mass-loss during protoplanetary disc dispersal via a process referred to as `boil-off’, in which confining pressure from the local gas […]

Astrochemistry, Astrogeology, Status Report

Protoplanetary Disk Chemistry

by Keith CowingSeptember 13, 2023September 13, 2023

Planets form in disks of gas and dust around young stars. The disk molecular reservoirs and their chemical evolution affect all aspects of planet formation, from the coagulation of dust […]

Comparison between the observed giant exoplanet population (gray dots) and all the simulations for the threeplanet systems. The initial values of these planets are denoted as orange for the case where the planets located in a wide configuration while brown dots denote planets located in a compact configuration, where the small numbers indicate the position of the first, second, and third planet. Purple, green and red data points symbolize the simulations for the different α, 10−3 , 3.16 · 10−4 and 10−4 respectively, whereas the coloured numbers shows the mean value and the standard deviation of the eccentricity for each case for all the simulated three- planet systems. The horizontal lines refers to the perihelion and aphelion of the planet a(1 ± e). The black dashed vertical line represents the current Radial Velocity (RV) detection limit at 5 AU. -- astro-ph.EP

Exoplanets, -moons, -comets, Status Report

Do All Gaps In Protoplanetary Discs Host Planets?

by Keith CowingJuly 27, 2023July 27, 2023

Following the assumption that the disc substructures observed in protoplanetary discs originate from the interaction between the disc and the forming planets embedded therein, we aim to test if these […]

Two dimensional map of the H2O and CO2 abundances of one quadrant of a disk around a low-mass star without a cavity (left) and with a 1 au cavity (right) 97. The dashed lines indicate the 70 and 200 K temperature contours; the blue line the τmid−IR = 1 line at 15 µm. The cavity radius is located between the H2O and CO2 snowlines. The disk model parameters are taken from ref. -- astro-ph.EP

Astrochemistry, Astrogeology, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Imaging & Spectroscopy, Status Report

The Diverse Chemistry Of Protoplanetary Disks As Revealed By JWST

by Keith CowingJuly 26, 2023July 26, 2023

Early results from the JWST-MIRI guaranteed time programs on protostars (JOYS) and disks (MINDS) are presented. Thanks to the increased sensitivity, spectral and spatial resolution of the MIRI spectrometer, the […]

Full MIRI/MRS spectrum of the Sz 98 disk. The extent per region is indicated, along with the detected species. The Spitzer LRS spectrum from the CASSIS database is shown in light grey (Lebouteiller et al. 2011). -- astro-ph.EP

Astrochemistry, Astronomy & Telescopes, Interstellar, Status Report

MINDS. Abundant Water And Varying C/O Across The Disk Of Sz 98 As Seen By JWST/MIRI

by Keith CowingJuly 19, 2023July 19, 2023

MIRI/MRS on board the JWST allows us to probe the inner regions of protoplanetary disks. Here we examine the disk around the classical T Tauri star Sz 98, which has […]

The distribution of upper level energies Eu and Einstein-A coefficients (top left and right plots, with color-coding reflecting Eu values) across infrared wavelengths naturally traces radial temperature gradients in inner disks within and across the water snowline (bottom plot, where the spectrum is scaled to a distance of 130 pc). Adapted from Figure 1 in Blevins et al. (2016) and Figure 13 in Banzatti et al. (2023). The MIRI lines used in the analysis in Section 3 are marked with black circles. -- astro-ph.EP

Astrochemistry, Astronomy & Telescopes, Imaging & Spectroscopy, Status Report

JWST Reveals Excess Cool Water Near The Snowline In Compact Disks, Consistent With Pebble Drift

by Keith CowingJuly 11, 2023July 11, 2023

Previous analyses of mid-infrared water spectra from young protoplanetary disks observed with the Spitzer-IRS found an anti-correlation between water luminosity and the millimeter dust disk radius observed with ALMA.

Example probability distributions of being unstable within 109 orbits for four different sets of adjacent pairs. An additional planet was inserted between the adjacent pair and the system was sampled 5000 times (using Rayleigh distributions with 𝜎𝑒 = 0.01, 𝜎𝑖 = 0.5 ◦ ). Each panel is a 2D histogram on a 25 by 25 grid showing the mean probability of all sampled configurations with an inserted planet whose mass and period fall within the bounds of each grid cell (white spaces have no inserted planets in that region). The white X shows the inserted planet’s mass and period for the adjacent pair’s FM13-style test. Each panel’s title shows its KIC, the placement of the inserted planet (0 is between the innermost planet and the second planet), the mean probability (p𝑚𝑒𝑎𝑛), the most stable configuration probability (p𝑀𝑆𝐶), and the probability of the pair’s FM13-style test (p𝐹𝑀13). Inserted planet periods are distributed uniformly in period and the masses according to Figure 1 (the vertical limits correspond to 95% of masses and 68% of masses fall within the region marked by the horizontal dashed lines). -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

On The Degree of Dynamical Packing In The Kepler Multi-planet Systems

by Keith CowingJune 27, 2023June 27, 2023

Current planet formation theories rely on initially compact orbital configurations undergoing a (possibly extended) phase of giant impacts following the dispersal of the dissipative protoplanetary disk.

An artist’s concept of a planet-forming disk around a young star. Astronomers using the MIRI spectrograph. © ALMA (ESO/NAOJ/NRAO) / MPIA

Astrochemistry, Astrogeology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release

JWST Looks Into The Chemical Components Of Exoplanet Formation

by Keith CowingApril 13, 2023

Researchers using the James Webb Space Telescope (JWST) have taken a first look at their data that probe the chemistry of the regions of disks around young stars where rocky […]

A schematic highlighting the physical evolution

Astrochemistry, Astrogeology, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Status Report

UV-driven Chemistry As A Signpost For Late-Stage Planet Formation

by Keith CowingJanuary 21, 2023January 21, 2023

The chemical reservoir within protoplanetary disks has a direct impact on planetary compositions and the potential for life.

Protoplanetary Disk

Experimental Study Of The Binding Energy Of NH3 On Different Types Of Ice And Its Impact On The Snow Line Of NH3 And H2O

Under The Light Of A New Star: Evolution Of Planetary Atmospheres Through Protoplanetary Disc Dispersal And Boil-off

Protoplanetary Disk Chemistry

Do All Gaps In Protoplanetary Discs Host Planets?

The Diverse Chemistry Of Protoplanetary Disks As Revealed By JWST

MINDS. Abundant Water And Varying C/O Across The Disk Of Sz 98 As Seen By JWST/MIRI

JWST Reveals Excess Cool Water Near The Snowline In Compact Disks, Consistent With Pebble Drift

On The Degree of Dynamical Packing In The Kepler Multi-planet Systems

JWST Looks Into The Chemical Components Of Exoplanet Formation

UV-driven Chemistry As A Signpost For Late-Stage Planet Formation

Impact Crater Hydrothermal Systems Support Rapid Microbial Enrichment and Diverse Metabolic Potential

Photometric and Spectroscopic Observations of Comet 2P/Encke’s Nucleus in the Mid-Infrared Wavelength Region

A New Method Maps An Exoplanet’s True Shape

Wavefront-Conditioned Photon Measurements for Exoplanet Spectroscopy: Contrast Limits and Conditional Gains

ExoPAG 35 – Early Career Talks Invitation