Himalayan Chandra Telescope Archives - Astrobiology

Observed spectra after dividing by the out-of-transit spectrum (residuals), shown in the stellar rest frame. Vertical orange and green dotted lines indicate the positions of the Na D2 and D1 lines, respectively. The region between the two horizontal dotted lines corresponds to in-transit observations, while regions outside represent out-of-transit data. The tilted red lines at the positions of Na D2 and D1 indicate the expected shift of the planetary absorption signal. -- astro-ph.EP

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

An Initial Assessment Of The Hanle Echelle Spectrograph For Exoplanet Atmosphere Studies

by Keith CowingSeptember 24, 2025September 24, 2025

Transmission spectroscopy is an effective technique for probing exoplanetary atmospheres.

Top: Extinction map of the local ISM viewed top-down taken from Dharmawardena et al. (2024). The Sun (yellow circle) is at X, Y = 0, 0 and the Galactic centre is at X, Y = 8.2, 0 kpc. The twelve targets (cf. Table 1) are represented by colored stars. The two stars analyzed in this paper are shown in red and the other ten are shown in blue. The small gray star near the center of this figure indicates 10 Lac (AV = 0.21 mag), which was used as a reference star. The contours represent extinction in steps of 0.2 mag. Bottom: Dust map of the Milky Way galactic plane derived from Gaia photometry (see Andrae et al. (2023) for more details) with the twelve targets following the same color scheme as above. Note that some of the targets overlap in this projection. -- astro-ph.GA

Astrochemistry, Astronomy & Telescopes, Biochemistry & Organic Chemistry, Biophysics, Biosignatures & Paleobiology, Imaging & Spectroscopy, Interstellar, Status Report

Investigating Silicate, Carbon, And Water In The Diffuse Interstellar Medium: The First Shots From WISCI

by Keith CowingJune 26, 2025June 26, 2025

The dusty interstellar medium (ISM) of the Milky Way is distributed in a complex, cloudy structure.