Exoplanetary Science

On Habitability around Red Dwarf Stars

September 29, 2015

Learning that there is flowing water on Mars encourages the belief that human missions there will have useful resources, perhaps in the form of underground aquifers that can be drawn upon not just as a survival essential but also to produce interplanetary necessities like rocket fuel. What yesterday’s NASA announcement cannot tell us, of course, […]

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New Look at β Pictoris b

September 17, 2015

Given the scale of our own Solar System, the system circling the star Beta Pictoris can’t help but give us pause. Imagine not only the orbiting clouds of gas, dust and debris that we would expect around a young star (8-20 million years old) with a solar system in formation, but also a gas giant […]

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Nitrogen Detection in the Exoplanet Toolkit

September 9, 2015

Extending missions beyond their initial goals is much on my mind as we consider the future of New Horizons and its possible flyby past a Kuiper Belt Object. But this morning I’m also reminded of EPOXI, which has given us views of the Earth that help us study what a terrestrial world looks like from […]

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Building the Gas Giants

August 20, 2015

Yesterday’s article on supernovae ‘triggers’ for star and planet formation shed some light on how a shock wave moving through a cloud of gas and dust could not only cause the collapse and contraction of a proto-star but also impart angular momentum to an infant solar system. Today’s essay focuses on a somewhat later phase […]

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Kepler-453b: A Hard to Find Transiting Circumbinary Planet

August 10, 2015

With the question of habitable planets on my mind following Andrew LePage’s splendid treatment of Kepler-452b on Friday, I want to turn to the interesting news out of San Diego State, where astronomer William Welsh and colleagues have been analyzing a new transiting circumbinary planet, a find that brings us up to a total of […]

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Is Kepler 452b a Rocky Planet or Not?

August 7, 2015

Where is the dividing line between a large, rocky planet and a ‘mini-Neptune?’ It’s a critical issue, because life is at least possible on one, unlikely on the other. But while we’re getting better at figuring out planetary habitable zones, the question of how large a planet can be and remain ‘terrestrial’ is still unresolved. […]

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A Brown Dwarf ‘Laboratory’ for Planet Formation

August 6, 2015

Detecting planets around brown dwarfs is tricky business, but it’s worth pursuing not only for its own sake but because planetary systems around brown dwarfs can tell us much about planet formation in general. A new paper from Andrzej Udalski (Warsaw University Observatory) and colleagues makes this point while noting four brown dwarf planets we’ve […]

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A ‘Rosetta Stone’ for Super-Earths

August 3, 2015

The discovery and confirmation of the exoplanet HD 219134b give us a useful touchstone relatively close to the Solar System. At 21 light years away in the constellation Cassiopeia, HD 219134b distinguishes itself by being the closest exoplanet to Earth to be detected using the transit method. That’s useful indeed, because we’ll be able to […]

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Earth 2.0: Still Looking

July 23, 2015

I’ve come to dislike the term ‘Earth 2.0.’ It’s not so much the idea of a second Earth as the use of 2.0, which in our technological era invariably recalls software updates. Windows 2.0 was better than Windows 1.0, but Windows 3.0 was the one that really took off — the idea here is that […]

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Detection of Pebbles in a Circumstellar Disk

July 9, 2015

Not long ago we looked at a new paper from Alan Boss that modeled interactions in young protoplanetary disks (A Disruptive Pathway for Planet Formation). The idea here is that as dust grains and larger objects bump into each other on the way to forming planetesimals, a mechanism must exist to keep them from spiraling […]

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