This column was written by my colleague, Elizabeth Tasker. Based in Tokyo, she is a scientist and communicator at the Japanese Space Agency JAXA and the Earth-Life Science Institute (ELSI). Her book, "The Planet Factory," was published last fall. This image shows the night side of Venus in thermal infrared. It is a false-color image …
Continue reading "To Understand Habitability, We Need to Return to Venus"
What observations, or groups of observations, would tell exoplanet scientists that life might be present on a particular distant planet? The most often discussed biosignature is oxygen, the product of life on Earth. But while oxygen remains central to the search for biosignatures afar, there are some serious problems with relying on that molecule. It …
I regret that the formatting of this column was askew earlier; I hope it didn't make reading too difficult. But now those problems are fixed. Behind the front page space science discoveries that tell us about the intricacies and wonders of our world are generally years of technical and intellectual development, years of planning and …
Continue reading "Putting Together a Community Strategy To Search for Extraterrestrial Life"
Huge escarpments of quite pure water ice have been found in the Southern Highlands of Mars -- accessible enough that astronauts might some day be able to turn the ice into water, hydrogen and oxygen. Some of these deposits are more than 100 meters thick and begin only a meter or two below the surface. …
Continue reading "The Mars Water Story Gets Ever More Interesting"
Unmanned missions to planets and moons and asteroids in our solar system have been some of NASA's most successful efforts in recent years, with completed or on-going ventures to Mars, Saturn, Jupiter, the asteroid Bennu, our moon, Pluto, Mercury and bodies around them all. On deck are a funded mission to Europa, another to Mars …
Continue reading "Two Tempting Reprise Missions: Explore Titan or Bring Back a Piece of A Comet"
By Elizabeth Tasker The media was abuzz last week with the latest NASA news conference. A neural network -- a form of artificial intelligence or machine learning -- developed at Google had found two planets in data previously collected by NASA’s prolific Kepler Space Telescope. It’s a technique that could ultimately track-down our most Earth-like …
The search for biosignatures in the atmospheres of distant exoplanets is extremely difficult and time-consuming work. The telescopes that can potentially take the measurements required are few and more will come only slowly. And for the current and next generation of observatories, staring at a single exoplanet long enough to get a measurement of the …
Continue reading "A New Way to Find Signals of Habitable Exoplanets?"
https://exoplanets.nasa.gov/system/video_items/107_WaterWorldHiH264.mp4 Water worlds, especially if they have no land on them, are unlikely to be home to life, or at least lifewe can detect. Some of the basic atmospheric and mineral cycles that make a planet habitable will be absent. Cool animation of such a world. (NASA) By guest columnist Elizabeth Tasker Wherever we …
It's tempting to look for habitable planets around red dwarf stars, which put out far less luminosity and so are less blinding. But is it wise? That question has been near the top of the list for many exoplanet scientists, especially those involved in the search for habitable worlds. Red dwarfs are plentiful (about three-quarters …
Continue reading "Red Dwarf Stars and the Planets Around Them"
Along the edge of an inlet on a tiny Japanese island can be found– side by side – striking examples of conditions on Earth some 2.4 billion years ago, then 1.4 billion years ago and then the Philippine Sea of today. First is a small channel with iron red, steaming and largely oxygen-free water – …
Continue reading "2.5 Billion Years of Earth History in 100 Square Feet"
Many Worlds 