Latest Terrestrial planet Stories
More than half the stars in our galaxy are small, dim M dwarfs. Until recently, scientists believed these stars put out too little light to support life on any planets that orbited them. Now, that opinion has changed.
Astronomers looking for earth-like planets in other solar systems â€” exoplanets â€” now have a new field guide thanks to earth and planetary scientists at Washington University in St. Louis.
Observations of 1 Ceres, the largest known asteroid, have revealed that the object may be a "mini planet," and may contain large amounts of pure water ice beneath its surface.
Most extrasolar planets discovered so far are "hot Jupiters," gas giants orbiting close to their parent stars. But according to current theory, such planets should form much farther from their stars, where temperatures are cold enough for water and other volatiles to freeze. How will scientists find the answer this mystery?
Last August, two groups of scientists announced the discovery of the smallest extrasolar planets found to date. But just what are these Neptune-size worlds? Are they gas giants, ice giants, or oversized Earths? Astronomer Alan Boss examines the possibilities.
In this interview with Astrobiology Magazine, Professor of Astronomy Geoff Marcy, one of the world's leading planet-hunters, reflects on recent other-worldly discoveries and speculates on what surprises may lay in store.
The most detailed measurements to date of the dusty disks around young stars confirm a new theory that the region where rocky planets such as Earth form is much farther away from the star than originally thought. These first definitive measurements of planet-forming zones offer important clues to the initial conditions that give birth to planets.
Looking for biosignatures that would be characteristic of intelligent life is not always about extrapolating the most intelligent things a species might be doing. For instance, would one look for pollutants in the atmosphere? Carnegie Institutions' Maggie Turnbull answers that and other questions from colleagues following her lecture, "Remote Sensing of Life and Habitable Worlds".
Maggie Turnbull, an astronomer with the Carnegie Institution, has spent many years thinking about what kind of stars could harbor Earth-like planets. Turnbull presented a talk, "Remote Sensing of Life and Habitable Worlds: Habstars, Earthshine and TPF." This edited transcript of the lecture is part two of a four-part series.
How many planets like the Earth are there among the 130 or so known planetary systems beyond our own? How many of these â€˜Earthsâ€™ could be habitable? Recent theoretical work at the Open University shows that as many as half of the known systems could be harbouring habitable â€˜Earthsâ€™ today.
Planetary and Space Science is a peer-reviewed scientific journal established in 1959 and published by Elsevier 15 times per year. As of May 2012, the editor-in-chief is Rita Schulz (The Netherlands). The journal publishes original research articles and short communications. The main focus is on solar system processes which encompass multiple areas of the natural sciences. Research that involves planetary and space sciences involves many disciplines. Celestial mechanics is part of these...
Terrestrial Planet Finder -- The Terrestrial Planet Finder is a proposed NASA telescope system capable of detecting extrasolar terrestrial planets. In May 2002, NASA chose two TPF mission architecture concepts for further study and technology development. Each would use a different means to achieve the same goal - to block the light from a parent star in order to see its much smaller, dimmer planets. That technology challenge has been likened to finding a firefly near the beam of...
Planet -- A planet is a body of considerable mass that orbits a star and that doesn't produce energy through nuclear fusion. Until recently, only nine were known (all of them in our own Solar system). As of the end of 2002 over 100 are known, with all of the new discoveries being extrasolar planets. Astronomers often call asteroids minor planets, and call the larger planetary bodies (those which are commonly called planets) major planets. Planets within the solar system can be...
Gas Giant -- A gas giant is a generic astronomical term invented by the science fiction writer James Blish to describe any large planet that is not composed mostly of rock or other solid matter. Gas giants may still have a solid core - in fact, it is expected that such a core is probably required for a gas giant to form - but the majority of its mass is in the form of gas (or gas compressed into a liquid state). Unlike rocky planets, gas giants do not have a well-defined surface. There...
Extrasolar Planet -- An extrasolar planet is a planet orbiting around a star other than the Sun. Extrasolar planets were first discovered in the 1990s as a result of improved telescope technology, CCD and computer-based image processing which allowed far more accurate measurements of stellar motions. The first extrasolar planets were reported by the astronomer Aleksander Wolszczan in 1993, orbiting the pulsar PSR 1257+12. Subsequent investigation has determined that they are only planets...
- An uxorious, effeminate, or spiritless man.
- A timorous, cowardly fellow.