TESS Archives - Page 29 of 33 - Astrobiology

Mass-radius diagram showing confirmed planets with mass uncertainties < 20% in grey circles, with TOI-544 b shown as the black circle. Left: the coloured tracks show different potential planet compositions from Zeng et al. (2019), assuming a planetary equilibrium temperature of 1000 K. The dashed lines show compositions of an Earth-like rocky core surrounded by a layer of H-He in varying percentages by mass, the solid lines show water world compositions with varying water mass fractions, the dotted lines show rocky and Earth-like rocky compositions. TOI-544 b is closest to the tracks with 100% H2O and 50% H2O with 50% rock. Right: the same as the left panel but the the dashed lines show compositions of an Earth-like rocky core surrounded by a layer of H-He in varying percentages by mass from Lopez & Fortney (2014) using the models for a 10Gyr planet, with solar metalicity and flux of 10F⊕, the solid lines show compositions from Aguichine et al. (2021) of irradiated ocean worlds with varying water mass fractions, and the dotted lines show the same rocky and Earth-like rocky compositions from Zeng et al. (2019). TOI-544 b is closest to models with either 30% water mass fraction, or a rocky core with a Hydrogen envelope of between 0.5 - 1%. The data is downloaded from the NASA Exoplanet Archive. -- astro-ph.EP

Astronomy & Telescopes, Atmospheres, Climate, Weather, Biosignatures & Paleobiology, Exploration Gear & Tech, Habitable Zones, Icy Worlds, Imaging & Spectroscopy, Status Report, Water/Hycean Worlds & Oceanography

TOI-544 b: A Potential Water-world Inside The Radius Valley In A Two-planet System

by Keith CowingOctober 24, 2023October 24, 2023

We report on the precise radial velocity follow-up of TOI-544 (HD 290498), a bright K star (V=10.8), which hosts a small transiting planet recently discovered by the Transiting Exoplanet Survey […]

TESS observations of TOI-904. Panel (a): Raw observations of each TESS sector, with 2-minute data shown in light grey and 10-minute binned data shown in dark grey. We show the Tukey biweight trend calculated with the wotan (Hippke et al. 2019) library of the variability is shown in dark blue. Each planet transit is denoted by an arrow at the bottom of the graph, with blue denoting transits of TOI-904 b and gold denoting transits TOI-904 c. Panel (b): TESS data detrended by the same fit, with each transit high-lighted in the same color as the arrows in the previous figure. Panel (c): The phase folded light curves of transits of TOI-904 b with the transit fit including a shaded region denoting 1σ uncertainty. Panel (d): The phase-folded light curves of TOI-904 c with the transit fit including a shaded region denoting 1σ uncertainty. -- astro-ph.EP

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

Separated Twins Or Just Siblings? A Multi-planet System Around An M Dwarf Including A Cool sub-Neptune

by Keith CowingOctober 24, 2023October 24, 2023

We report the discovery of two TESS sub-Neptunes orbiting the early M dwarf TOI-904 (TIC 261257684). Both exoplanets, TOI-904 b and c, were initially observed in TESS sector 12 with […]

Individual components of our 3-planet RV model of TOI-1266 and corresponding GLS periodograms. From top to bottom: the raw LBL RVs, stellar RV activity, TOI-1266 b, TOI-1266 c, the planet candidate TOI-1266 d, and the residuals. The residuals do not show any evidence for unaccounted periodicities in the GLS. The vertical shaded regions in the left column highlight each TESS sector’s observing window (annotated at the top) and reveals where we have contemporaneous TESS and spectroscopic observations. Similarly, the vertical dashed lines highlight the epochs of our ground-based transit observations of either TOI-1266 b or c, using the ARCTIC and WIRC cameras. The vertical dashed lines in the right column depict the orbital periods of the transiting TOI-1266 planets, the candidate planet d, and the stellar rotation period inferred from our 𝐻 𝛼 time series. -- astro-ph.EP

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Status Report

Masses, Revised Radii, and a Third Planet Candidate in the “Inverted” Planetary System Around TOI-1266

by Keith CowingOctober 24, 2023October 24, 2023

Is the population of close-in planets orbiting M dwarfs sculpted by thermally driven escape or is it a direct outcome of the planet formation process? A number of recent empirical […]

Mass-radius diagram for TOI-1801 b, together with all known exoplanets (grey dots) with a precision better than 8% in radius (through transit) and 20% in mass (from RV). The population of young transiting exoplanets (< 900 Myr) with measured masses is plotted as coloured dots, according to their ages. The uncertainties on TOI-1801 b are shown as coloured shaded regions with 1, 2, and 3σ levels of confidence. In the left panel, the iso-density lines are displayed as dashed grey lines. In the remaining panels where the population of exoplanets is plotted along with TOI-1801 b, coloured lines indicate different composition models without gas (middle panel) and with a gas envelope (right panel) from Zeng et al. (2019). In the right panel, the solid and dotted lines show the models with temperatures of 300 K and 500 K, respectively, of the corresponding specific entropy at 100 bar level in the gas envelope. The Earth and Neptune are also depicted as reference. We include B22 and M22 as references because different results have been published for the same planet, and this refers to Barragán et al. (2022) and El Mufti et al. (2023), respectively. -- astro-ph.EP

Exoplanets, -moons, -comets, Habitable Zones, Status Report

TOI-1801 b: A Temperate Mini-Neptune Around A Young M0.5 Dwarf

by Keith CowingOctober 17, 2023October 17, 2023

We report the discovery, mass, and radius determination of TOI-1801 b, a temperate mini-Neptune around a young M dwarf. TOI-1801 b was observed in TESS sectors 22 and 49, and […]

Broadband light curves of the flare-affected transits of TRAPPIST-1b and f. The transit models are shown in orange, and the exponential fit to the integrations in both the transit and flare is shown in blue. The exponential fit is necessary to determine the shape of the transit light curve. As shown in the O-C diagrams at the bottom, we use an initial guess of c1 and c2 to fit the exponential, then subtract the exponential to obtain final values of c1 and c2. We note c1 and c2 represent the coefficients of the quadratic limb darkening equation. The first and third O-C diagrams are directly comparable and show the light curve with the final transit model removed. The middle O-C diagram shows an intermediate step in the determination of the TRAPPIST-1f transit model fit in which the initial guess on the transit model is subtracted prior to fitting and subtracting the exponential. The residuals of the middle panel therefore show the quality of the exponential fit. -- astro-ph.SR

Exoplanets, -moons, -comets, Habitable Zones, Radiation, Space Weather & Heliophysics, Status Report, TRAPPIST-1

Characterizing The Near-infrared Spectra Of Flares From TRAPPIST-1 During JWST Transit Spectroscopy Observations

by Keith CowingOctober 9, 2023October 9, 2023

We present the first analysis of JWST near-infrared spectroscopy of stellar flares from TRAPPIST-1 during transits of rocky exoplanets. Four flares were observed from 0.6–2.8 μm with NIRISS and 0.6–3.5 […]

The architecture and HZ of the GJ 357 system, where the scale of the figure is 0.57 AU along each side. The CHZ is shown in light green, the OHZ extensions to the HZ are shown in dark green, and the orbits of the known planets are shown as solid circles. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Habitable Zones, Status Report

GJ 357 d: Potentially Habitable World or Agent of Chaos?

by Keith CowingOctober 4, 2023October 4, 2023

Multi-planet systems provide important laboratories for exploring dynamical interactions within the range of known exoplanetary system architectures.

The TP profiles for the 6 exoEarth atmospheres (left panel) and the chemical abundance profiles for the 400 ppm exoEarth (right panel).

Astrogeology, Astronomy & Telescopes, Biosignatures & Paleobiology, Exoplanets, -moons, -comets, Habitable Zones, Imaging & Spectroscopy, Status Report, Venus

Investigating The Ability Of JWST To Identify Discerning Features In exoEarth And exoVenus Transmission Spectra

by Keith CowingOctober 4, 2023October 4, 2023

The success of the Transiting Exoplanet Survey Satellite (TESS) mission has led to the discovery of an abundance of Venus Zone (VZ) terrestrial planets that orbit relatively bright host stars.

Comparison between spectroscopically derived Teff from GALAH, APOGEE, and LAMOST to our photometrically derived Teff values for both main sequence fitting (left) and pre-main sequence fitting (right). For each survey, we list the number of targets and the median spectroscopic Teff uncertainty in parentheses. -- astro-ph.SR

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

Using Photometrically-Derived Properties of Young Stars to Refine TESS’s Transiting Young Planet Survey Completeness

by Keith CowingAugust 27, 2023August 27, 2023

The demographics of young exoplanets can shed light onto their formation and evolution processes. Exoplanet properties are derived from the properties of their host stars.

Results of the transit injection-and-recovery tests performed on the TESS (upper panel) and CHEOPS (lower panel) data to assess the detectability of potential additional transiting planets in the TOI-178 system. For both panels, the red stars show the locations of the 6 known planets in the system. -- astro-ph.EP

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

Refining The Properties Of The TOI-178 System With CHEOPS And TESS

by Keith CowingAugust 23, 2023August 23, 2023

The TOI-178 system consists of a nearby late K-dwarf transited by six planets in the super-Earth to mini-Neptune regime, with orbital periods between 1.9 and 20.7 days.

Starfield around TOI-4336.01 in TESS Sector 38 used by TRICERATOPS in its FPP and nearby false positive probability (NFPP) calculations. Left: plot of the positions of each star within 2.5 arcminutes centered on the target with the color of each point representing the TESS magnitude of the star. The overlaid grid denotes the TESS pixel borders with pixel column and row numbers labeled on the X and Y axis, respectively. The dashed gray circle represents a distance of 2.5 arcminutes and the red squares denote the extraction aperture used by the SPOC when generating the PDC SAP light curve for this TESS sector. Right: Same as left but instead of displaying each background star near the target, TESS data are shown. The SPOC extraction aperture is in red and the colormap represents the flux captured by each TESS pixel. -- astro-ph.EP

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

Identification Of The Top TESS Objects Of Interest For Atmospheric Characterization Of Transiting Exoplanets With JWST

by Keith CowingAugust 21, 2023August 21, 2023

JWST has ushered in an era of unprecedented ability to characterize exoplanetary atmospheres. While there are over 5,000 confirmed planets, more than 4,000 TESS planet candidates are still unconfirmed and […]