Astronomers Propose New Definition of Planet
Established in 2006 by the International Astronomical Union, the current definition specifies that to qualify as a planet, a celestial body must orbit the Sun within our Solar System. But…
Scientists Revise Famous Drake Equation
Within the uncertainties of involved astronomical and biological parameters, the Drake equation typically predicts that there should be many exoplanets (< 100 to millions) in our Milky Way Galaxy hosting active,…
Study: Jupiter’s Moon Io Has Been Volcanically Active for All of Its History
Sulfur and chlorine isotopes in Io’s atmosphere indicate that it has been volcanically active for the entire 4.57 billion-year history of the Solar System. This global view of Io was…
Uninhabitable Venus Offers Lessons about Potential for Extraterrestrial Life
Fully understanding how a rocky planet becomes habitable and remains so is a fundamental challenge for planetary scientists and astrobiologists, given the diversity and complexity of intrinsic and extrinsic processes…
SOHO Observatory Discovers Its 5,000th Comet
On March 25, 2024, Hanjie Tan, an astronomy Ph.D. student in Prague, Czech Republic, spotted a comet in an image from the ESA/NASA Solar and Heliospheric Observatory (SOHO) spacecraft, which…
Tricarbon Molecule Detected in Atmosphere of Titan
The tricarbon molecule (C3) is likely produced in the upper atmosphere of Titan by the reaction of abundant acetylene with atomic carbon. This view of Titan is among the last…
Asteroid Moonlet Dimorphos May Have Been Reshaped Following Impact from NASA’s DART Mission
On September 26, 2022, NASA’s Double Asteroid Redirection Test (DART) mission successfully impacted Dimorphos, the natural satellite of the binary near-Earth asteroid Didymos. New numerical simulations indicate that the DART…
Webb Finds Evidence of Hydrothermal Processes in Interiors of Eris and Makemake
The icy dwarf planets Eris and Makemake have surfaces bearing methane ice of unknown origin. According to an analysis of data from the NASA/ESA/CSA James Webb Space Telescope, Eris and…
SOFIA Detects Molecular Water on Nominally Dry Asteroids
Using the FORCAST instrument on NASA’s retired Stratospheric Observatory for Infrared Astronomy (SOFIA), astronomers have obtained mid-infrared spectra of four S-type (silicate-rich) asteroids: Iris, Parthenope, Melpomene, and Massalia. They’ve detected…
New Research Sheds Light on Internal Structure of Dwarf Planet Eris
The trans-Neptunian dwarf planet Eris is tidally locked to its small moon Dysnomia. Recently obtained bounds on the mass of Dysnomia demonstrate that Eris must be unexpectedly dissipative (‘squishy’) for…