Exoplanetary Science

HD 142527: Shadows of a Tilted Disk

January 14, 2015

About a year ago we looked at a young star called HD 142527 in the constellation Lupus (see HD 142527: An Unusual Circumstellar Disk). A T Tauri star about five million years old, HD 142527 has drawn attention because it shows evidence of both an inner and an outer disk, each of which may be […]

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Gemini Planet Imager: Early Success at Cerro Pachon

January 8, 2015

Working at near-infrared wavelengths, the Gemini Planet Imager, now entering regular operations at the Gemini South Telescope in Cerro Pachon (Chile), is producing striking work, including images of exoplanets and circumstellar disks. Have a look at the image below, which highlights the instrument’s ability to achieve high contrast at small angular separations. Such capabilities make […]

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Closing on Earth 2.0?

January 7, 2015

The eight ‘habitable zone’ planets we discussed yesterday appear today in a much broader context. The Kepler mission has verified its 1000th planet, and with the detection of 554 more planet candidates, the total candidate count has now reached 4175. According to this NASA news release, six of the new planet candidates are near-Earth size […]

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AAS: 8 New Planets in Habitable Zone

January 6, 2015

One way to confirm the existence of a transiting planet is to run a radial velocity check to see if it shows up there as a gravitationally induced ‘wobble’ in the host star. But in many cases, the parent stars are too far away to allow accurate measurements of the planet’s mass. What Guillermo Torres […]

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Oceans on a Larger ‘Earth’

January 5, 2015

We often think about how thin Earth’s atmosphere is, imagining our planet as an apple, with the atmosphere no thicker than the skin of the fruit. That vast blue sky can seem all but infinite, but the great bulk of it is within sixteen kilometers of the surface, always thinning as we climb toward space. […]

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Kepler: Thoughts on K2

December 29, 2014

As we start thinking ahead to the TESS mission (Transiting Exoplanet Survey Satellite), currently scheduled for launch in 2017, the exoplanet focus sharpens on stars closer to home. The Kepler mission was designed to look at a whole field of stars, 156,000 of them extending over portions of the constellations Cygnus, Lyra and Draco. Most […]

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A New Look at High Obliquity Exoplanets

December 18, 2014

Looking forward from winter into spring in North America — unfortunately still a few months out — I can thank Earth’s obliquity for a seasonal change I enjoy more every year. Obliquity is the angle that our planet’s rotational axis makes as it intersects the orbital plane, which in the case of Earth is 23.5°, […]

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The Virtues of Oddly Shaped Planets

December 16, 2014

A new paper out of George Mason University tackles the subject of planets deformed by tidal effects in close proximity to their star. It’s a useful study for reasons I’ll explain in a moment, but first a digression: I once had the chance to talk physics with the late Sheridan Simon, who besides being a […]

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Young Planets, Young Stars

December 8, 2014

We’re going to be bringing both space- and ground-based assets to bear on the detection of rocky planets within the habitable zone in coming years. Cool M-class stars (red dwarfs) stand out in this regard because their habitable zones (in this case defined as where water can exist in liquid form on the surface) are […]

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Enter the ‘Mirage Earth’

December 3, 2014

A common trope from Hollywood’s earlier decades was the team of explorers, or perhaps soldiers, lost in the desert and running out of water. On the horizon appears an oasis surrounded by verdant green, but it turns out to be a mirage. At the University of Washington, graduate student Rodrigo Luger and co-author Rory Barnes […]

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