Oxygen in the atmosphere may not be an entirely reliable ‘biosignature,’ but there are ways to distinguish false positives from signs of life, scientists say. In the search for life on other planets, the presence of oxygen in a planet’s atmosphere is one potential sign of biological activity that might be detected by future telescopes. A new study, however, describes several scenarios in which a lifeless rocky planet around a sun-like star could evolve to have oxygen in its atmosphere.  By varying the initial inventory of volatile elements in a model of the geochemical evolution of rocky ..read more

First we need to know more about molecules in the atmosphere. Scientists shed more light on molecules linked to life on other planets. To confirm life on other planets, we need to detect far more molecules in their atmospheres than we currently do to rule out non-biological chemical processes. Phosphine detected in the atmosphere of Venus has scientists divided about whether or not it signifies primitive life on the planet. Image: Shutterstock The search for life on other planets has received a major boost after scientists revealed the spectral signatures of almost 1000 atmospheric molecules t ..read more

Three decades after Cornell astronomer Carl Sagan suggested that Voyager 1 snap Earth’s picture from billions of miles away – resulting in the iconic Pale Blue Dot photograph – two astronomers now offer another unique cosmic perspective. Some exoplanets – planets from beyond our own solar system – have a direct line of sight to observe Earth’s biological qualities from far, far away. 30 years ago, Carl Sagan requested the Voyager 1 spacecraft take one last picture of Earth. This is the legacy of the Pale Blue Dot. Lisa Kaltenegger, associate professor of astronomy in the College of ..read more

This composite image of the cloud-covered planet Venus uses data from the Japanese probe Akatsuki. Institute of Space and Astronautical Science/Japan Aerospace Exploration Agency A growing body of research suggests the planet Venus may have had an Earth-like environment billions of years ago, with water and a thin atmosphere. Yet testing such theories is difficult without geological samples to examine. The solution, according to Yale astronomers Samuel Cabot and Gregory Laughlin, may be closer than anyone realized. Cabot and Laughlin say pieces of Venus — perhaps billions of them — are likely ..read more

New research from The University of Texas at Austin has used dry Martian lake beds to determine how much precipitation was present on the ancient planet. A new study from The University of Texas at Austin is helping scientists piece together the ancient climate of Mars by revealing how much rainfall and snowmelt filled its lake beds and river valleys 3.5 billion to 4 billion years ago. The study, published in Geology, represents the first time that researchers have quantified the precipitation that must have been present across the planet, and it comes out as the Mars 2020 Perseverancerov ..read more

An artist’s rendering of the Nancy Grace Roman Telescope. Graphic courtesy NASA. An upcoming NASA mission could find that there are more rogue planets – planets that float in space without orbiting a sun – than there are stars in the Milky Way, a new study theorizes. Samson Johnson “This gives us a window into these worlds that we would otherwise not have,” said Samson Johnson, an astronomy graduate student at The Ohio State University and lead author of the study. “Imagine our little rocky planet just floating freely in space – that’s what this mission will help us find.” The s ..read more

The dwarf planet Ceres, about 940 kilometers (585 miles) in diameter, is the largest body in the main asteroid belt. NASA’s Dawn spacecraft mapped the planet and found evidence — a low-density region of the crust (blue) — of an underground brine reservoir. A crater named Occator is to the left of the blue area This composite image shows gravity anomalies (red is high, blue is low) on the right side and Ceres’ real colors on the left. The bright spots are near the center of Occator. (Image courtesy of Anton Ermakov, UC Berkeley, NASA/JPL) An analysis of low-altitude data from flyovers of Ceres ..read more

In this illustration, NASA’s Ingenuity Mars Helicopter stands on the Red Planet’s surface as NASA’s Perseverance rover (partially visible on the left) rolls away. Image Credit: NASA/JPL-Caltech The first helicopter attempting to fly on another planet is a marvel of engineering. Get up to speed with these key facts about its plans. When NASA’s Mars 2020 Perseverance rover launches from Cape Canaveral Air Force Station in Florida later this summer, an innovative experiment will ride along: the Ingenuity Mars Helicopter. Ingenuity may weigh only about 4 pounds (1.8 kilograms), but it has some out ..read more

The trigger for “Snowball Earth” global ice ages may have been drops in incoming sunlight that happened quickly, in geological terms, according to an MIT study. Image: Wikimedia, Oleg Kuznetsov At least twice in Earth’s history, nearly the entire planet was encased in a sheet of snow and ice. These dramatic “Snowball Earth” events occurred in quick succession, somewhere around 700 million years ago, and evidence suggests that the consecutive global ice ages set the stage for the subsequent explosion of complex, multicellular life on Earth. Scientists have considered multiple scenarios for what ..read more

Using advanced techniques, scientists have detected organic compounds containing nitrogen in Martian meteorites which were ejected from Mars’ surface ~ 15 million years ago, proving that evidence for early life can be preserved and detected today A research team including research scientist Atsuko Kobayashi from the Earth-Life Science Institute (ELSI) at Tokyo Institute of Technology, Japan and research scientist Mizuho Koike from the Institute of Space and Astronautical Science at Japan Aerospace Exploration Agency, have found nitrogen-bearing organic material in carbonate minerals in a Marti ..read more