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TESS Discovery of an Ultra-short-period Planet around the Nearby M Dwarf LHS 3844

Journal Article

Data from the newly commissioned Transiting Exoplanet Survey Satellite has revealed a "hot Earth" around LHS 3844, an M dwarf located 15 pc away. The planet has a radius of  R _⊕ and orbits the star every 11 hr. Although the existence of an atmosphere...

K2-263 b: a 50 d period sub-Neptune with a mass measurement using HARPS-N

Journal Article

This paper reports on the validation and mass measurement of K2-263 b, a sub-Neptune orbiting a quiet G9V star. Using K2 data from campaigns C5 and C16, we find this planet to have a period of 50.818947 ± 0.000094 d and a radius of 2.41 ± 0.12 R_⊕. We...

TESS Discovery of a Transiting Super-Earth in the pi Mensae System

Journal Article

We report the detection of a transiting planet around π Men (HD 39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The solar-type host star is unusually bright (V = 5.7) and was already known to host a Jovian planet on a highly...

Visible-Spanning Flat Supercontinuum for Astronomical Applications

Journal Article

We demonstrate a broad, flat, visible supercontinuum spectrum that is generated by a dispersion-engineered tapered photonic crystal fiber pumped by a 1 GHz repetition rate turn-key Ti:sapphire laser outputting ~30 fs pulses at 800 nm. At a pulse energy...

UV photostability of three 2-aminoazoles with key roles in prebiotic chemistry on the early earth†

Journal Article

Three related molecules in the 2-aminoazole family are potentially important for prebiotic chemistry: 2-aminooxazole, 2-aminoimidazole, and 2-aminothiazole, which can provide critical functions as an intermediate in nucleotide synthesis, a nucleotide...

A New Desalination Pump Help Define the pH of Ocean Worlds

Journal Article

We study ocean exoplanets, for which the global surface ocean is separated from the rocky interior by a high-pressure ice mantle. We describe a mechanism that can pump salts out of the ocean, resulting in oceans of very low salinity. Here we focus on the...

UV‐Induced Charge‐Transfer States in Short Guanosine‐Containing DNA Oligonucleotides

Journal Article

Charge transfer has proven to be an important mechanism in DNA photochemistry. In particular, guanine (dG) plays a major role as an electron donor, but the photophysical dynamics of dG‐containing charge‐transfer states have not been extensively...

The origin of life as a planetary phenomenon

Journal Article

We advocate an integrative approach between laboratory experiments in prebiotic chemistry and geologic, geochemical, and astrophysical observations to help assemble a robust chemical pathway to life that can be reproduced in the laboratory. The...

Ultraviolet-Driven Deamination of Cytidine Ribonucleotides Under Planetary Conditions

Journal Article

A previously proposed synthesis of pyrimidine ribonucleotides makes use of ultraviolet (UV) light to convert β-uc(d)-ribocytidine-2',3'-cyclic phosphate to β-uc(d)-ribouridine-2',3'-cyclic phosphate, while simultaneously selectively degrading synthetic...

Cometary Delivery of Hydrogen Cyanide to the Early Earth

Journal Article

Delivery of water and organics by asteroid and comet impacts may have influenced prebiotic chemistry on the early Earth. Some recent prebiotic chemistry experiments emphasize hydrogen cyanide (HCN) as a feedstock molecule for the formation of sugars...

How Flat Can a Planetary System Get? I. The Case of TRAPPIST-1

Journal Article

The seven planets orbiting TRAPPIST-1 in a compact near-resonant chain offer a unique case to study in planet formation theory. We demonstrate in this paper that the remarkable flatness of the system, exceeding that of any other known planetary system, is...

Detection Limits of Low-mass, Long-period Exoplanets Using Gaussian Processes Applied to HARPS-N Solar Radial Velocities

Journal Article

Radial velocity (RV) searches for Earth-mass exoplanets in the habitable zone around Sun-like stars are limited by the effects of stellar variability on the host star. In particular, suppression of convective blueshift and brightness inhomogeneities due...