The triumphant Cassini mission to Saturn will be coming to an end on September 15, when the spacecraft dives into the planet. Running out of fuel, NASA chose to end the mission that way rather than run the risk of having the vehicle wander and ultimately land on Europa or Enceladus, potentially contaminating two …
Primordial Asteroids, And The Stories They Are Telling
Asteroid, we've long been told, started tiny in our protoplanetary disk and only very gradually became more massive through a process of accretion. They collected dust from the gas cloud that surrounded our new star, and then grew larger through collisions with other growing asteroids. But in recent years, a new school of thought …
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In Search of Panspermia (and Life on Icy Moons)
Sometimes personal affairs intervene for all of us, and they have now for your Many Worlds writer and his elderly father. But rather than remain off the radar screen, I wanted to repost this column which has a new import. It turns out that versions of the instrument described below -- a miniature gene …
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Phobos and Deimos: Captured Asteroids or Cut From Ancient Mars?
Illustration of Mars with its two moons, Phobos and Deimos. (NASA/JPL-Caltech/Malin Space Science Systems/Texas A&M Univ.) The global success rate for sending missions to land on the moons of Mars has hardly been impressive -- coming in at zero out of three attempts. They were all led by the Russian (or former Soviet) space agencies, …
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Where Should We Look for Ancient Biosignatures on Mars in 2020?
One of the great successes of the Curiosity mission to Mars is that the rover landed at what turned out to be a goldmine of a location. The mission has once and for all determined that the planet was habitable at least during its early days, that it contains the organic building blocks of life, …
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The Very Influential Natalie Batalha
I'd like to make a slight detour and talk not about the science of exoplanets and astrobiology, but rather a particular exoplanet scientist who I've had the pleasure to work with. The scientist is Natalie Batalha, who has been lead scientist for NASA's landmark Kepler Space Telescope mission since soon after it launched in 2009, …
NASA Panel Supports Life-Detecting Lander for Europa; Updated
As I prepare for the Astrobiology Science Conference (Abscicon) next week in Arizona, I'm struck by how many speakers will be discussing Europa missions, Europa science, ocean worlds and habitability under ice. NASA's Europa Clipper mission to orbit that moon, scheduled for launch to the Jupiter system in the mid 2020s, explains part of the …
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Ocean Worlds: Enceladus Looks Increasingly Habitable, and Europa’s Ocean Under the Ice More Accessible to Sample
It wasn't that long ago that Enceladus, one of 53 moons of Saturn, was viewed as a kind of ho-hum object of no great importance. It was clearly frozen and situated in a magnetic field maelstrom caused by the giant planet nearby and those saturnine rings. That view was significantly modified in 2005 when scientists …
What Scientists Expect to Learn From Cassini’s Upcoming Plunge Into Saturn
Seldom has the planned end of a NASA mission brought so much expectation and scientific high drama. The Cassini mission to Saturn has already been a huge success, sending back iconic images and breakthrough science of the planet and its system. Included in the haul have been the discovery of plumes of water vapor spurting …
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Ceres, Asteroids And Us
For most of us, asteroids exist primarily as a threat. An asteroid that landed around the Yucatan peninsula, after all, is generally considered to have set into motion the changes that resulted in the elimination of the dinosaurs. Other large in-coming asteroids laid waste to swaths of Siberia in 1908, dug the world's largest crater …
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