Sediment Archives

March 11, 2021March 11, 2021 by Matt Williams

Microbes Found That Survive on the by-Products of Radioactive Decay

The rocks seen here along the shoreline of Lake Salda in Turkey were formed over time by microbes that trap minerals and sediments in the water. These so-called microbialites were once a major form of life on Earth and provide some of the oldest known fossilized records of life on our planet. NASA's Mars 2020 Perseverance mission will search for signs of ancient life on the Martian surface. Studying these microbial fossils on Earth has helped scientists prepare for the mission. Image Credit: NASA/JPL-Caltech

In addition to investigating the big questions about life in our Universe (origins, evolution, distribution, etc.), one of the chief aims of astrobiologists is to characterize extraterrestrial environments to determine if life could exist there. However, there are still unresolved questions about the range of conditions under which life can survive and thrive. Placing better constraints on this will help astrobiologists search for life beyond Earth.

To get a better understanding of how ecosystems can exist beneath the ocean floor (so far from the Sun) a team of researchers led by the University of Rhode Island’s Graduate School of Oceanography (GSO) conducted a study on microbes in ancient seafloor sediment. What they found, to their surprise, was that these lifeforms are sustained primarily by chemicals created by the natural irradiation of water molecules.

May 13, 2020May 13, 2020 by Evan Gough

Sediments on Mars, Created By Blowing Wind or Flowing Water

The HiRISE Picture of the Day from May 9th 2020. Sedimentary rocks in and impact crater on Mars. Image Credit: NASA/JPL/UArizona

The HiRISE (High-Resolution Imaging Science Experiment) instrument on NASA’s Mars Reconnaissance Orbiter (MRO) has given us a steady stream of images of the Martian surface. It’s been in orbit around Mars since March 2006, and has greatly outlived its intended mission length.

One of the latest Hi-PODs, or HiRISE Pictures of the Day, is this one, of sedimentary rock on Mars being eroded away.

April 30, 2020April 30, 2020 by Evan Gough

NASA’s Perseverance Rover is Going to Jezero Crater, Which is Looking Better and Better as a Place to Search for Evidence of Past Life on Mars

Jezero Crater on Mars is the landing site for NASA's Mars 2020 rover. Image Credit: NASA/JPL-Caltech/ASU

In 2018, NASA decided that the landing site for its Mars 2020 Perseverance rover would be the Jezero Crater. At the time, NASA said the Jezero Crater was one of the “oldest and most scientifically interesting landscapes Mars has to offer.” That assessment hasn’t changed; in fact it’s gotten stronger.

A new research paper says that the Jezero Crater was formed over time periods long enough to promote both habitability, and the preservation of evidence.