Tag Archives: kepler

Earthlike ‘Star Wars’ Tatooines may be common

Simulations dispute dogma: rocky planets may orbit many double stars

Luke Skywalker’s home in “Star Wars” is the desert planet Tatooine, with twin sunsets because it orbits two stars. So far, only uninhabitable gas-giant planets have been identified circling such binary stars, and many researchers believe rocky planets cannot form there. Now, mathematical simulations show that Earthlike, solid planets such as Tatooine likely exist and may be widespread. (more…)

Read More

The Most Precise Measurement of an Alien World’s Size

Thanks to NASA’s Kepler and Spitzer Space Telescopes, scientists have made the most precise measurement ever of the radius of a planet outside our solar system. The size of the exoplanet, dubbed Kepler-93b, is now known to an uncertainty of just 74 miles (119 kilometers) on either side of the planetary body.

The findings confirm Kepler-93b as a “super-Earth” that is about one-and-a-half times the size of our planet. Although super-Earths are common in the galaxy, none exist in our solar system. Exoplanets like Kepler-93b are therefore our only laboratories to study this major class of planet. (more…)

Read More

Kepler Finds a Very Wobbly Planet

Imagine living on a planet with seasons so erratic you would hardly know whether to wear Bermuda shorts or a heavy overcoat. That is the situation on a weird, wobbly world found by NASA’s planet-hunting Kepler space telescope.

The planet, designated Kepler-413b, precesses, or wobbles, wildly on its spin axis, much like a child’s top. The tilt of the planet’s spin axis can vary by as much as 30 degrees over 11 years, leading to rapid and erratic changes in seasons. In contrast, Earth’s rotational precession is 23.5 degrees over 26,000 years. Researchers are amazed that this far-off planet is precessing on a human timescale. (more…)

Read More

NASA’s Kepler Provides Insights on Enigmatic Planets

More than three-quarters of the planet candidates discovered by NASA’s Kepler spacecraft have sizes ranging from that of Earth to that of Neptune, which is nearly four times as big as Earth. Such planets dominate the galactic census but are not represented in our own solar system. Astronomers don’t know how they form or if they are made of rock, water or gas.

The Kepler team today reports on four years of ground-based follow-up observations targeting Kepler’s exoplanet systems at the American Astronomical Society meeting in Washington. These observations confirm the numerous Kepler discoveries are indeed planets and yield mass measurements of these enigmatic worlds that vary between Earth and Neptune in size. (more…)

Read More

Blowing Up Stars

*For his discoveries about the lives and deaths of stars, the exotic physics of black holes and the origin of chemical elements, UA Regents’ Professor David Arnett has been honored with the Henry Norris Russell Lectureship.*

What happens when a star dies? How does a black hole form? What makes the chemical elements that form the building blocks of stars, planets and living beings?

Those are the kinds of questions that have fascinated David Arnett, a Regents’ Professor at the University of Arizona’s Steward Observatory, from an early age. (more…)

Read More

NASA’s Kepler Mission Finds Three Smallest Exoplanets

PASADENA, Calif. – Astronomers using data from NASA’s Kepler mission have discovered the three smallest planets yet detected orbiting a star beyond our sun. The planets orbit a single star, called KOI-961, and are 0.78, 0.73 and 0.57 times the radius of Earth. The smallest is about the size of Mars.

All three planets are thought to be rocky like Earth but orbit close to their star, making them too hot to be in the habitable zone, which is the region where liquid water could exist. Of the more than 700 planets confirmed to orbit other stars, called exoplanets, only a handful are known to be rocky. (more…)

Read More

NASA’s Kepler Confirms Its First Planet in Habitable Zone

PASADENA, Calif. — NASA’s Kepler mission has confirmed its first planet in the “habitable zone,” the region around a star where liquid water could exist on a planet’s surface. Kepler also has discovered more than 1,000 new planet candidates, nearly doubling its previously known count. Ten of these candidates are near-Earth-size and orbit in the habitable zone of their host star. Candidates require follow-up observations to verify they are actual planets.

The newly confirmed planet, Kepler-22b, is the smallest yet found to orbit in the middle of the habitable zone of a star similar to our sun. The planet is about 2.4 times the radius of Earth. Scientists don’t yet know if Kepler-22b has a predominantly rocky, gaseous or liquid composition, but its discovery is a step closer to finding Earth-like planets. (more…)

Read More

Earth-Size Planet Candidates Found in Habitable Zone

PASADENA, Calif. — NASA’s Kepler mission has discovered its first Earth-size planet candidates and its first candidates in the habitable zone, a region where liquid water could exist on a planet’s surface. Five of the potential planets are near Earth-size and orbit in the habitable zone of smaller, cooler stars than our sun.

Candidates require follow-up observations to verify they are actual planets. Kepler also found six confirmed planets orbiting a sun-like star, Kepler-11. This is the largest group of transiting planets orbiting a single star yet discovered outside our solar system. (more…)

Read More