TOP 100 SCIENCE SITES
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| Letters: Headaches and Bedtime (1 Letter) Letters to the editor. feeds.nytimes.com |
Today's mystery bird for you to identify This gorgeous neotropical migrant will be a very challenging bird for you to identify, but I am sure most of you can narrow it down to one of two very similar speciesMystery bird photographed in southern California, USA. [I will identify this bird for you in 48 hours] Image: Steve Duncan. [larger view].Nikon D200 w/ manual Nikkon 600 f/4 on tripod w/ gimbal mount.This neotropical migrant will be a very challenging bird for you to identify, but I am sure most of you can narrow it down to one of two very similar species. Daily Mystery Bird Rules: 1. Please name at least one field mark that supports your identification, keeping in mind that more than one field mark is often necessary to distinguish between species. IDs without any supporting information are not valid and may be deleted by the moderators. 2. Expert and intermediate level birders: do NOT try to be the first to blurt out the mystery bird's ID. Instead, please provide helpful hints, such as descriptions, literary references, puns, personal anecdotes, and other forms of discussion and assistance for beginning birders and for those following on their iPhones without naming the species. Expert and intermediate birders are free to name the bird species 24 or more hours after it was first published.3. Each mystery bird is usually accompanied by a question or two. These questions can be useful for identifying the pictured species, but may instead be used to illustrate an interesting aspect of avian biology, behaviour or evolution, or may be intended to generate conversation on other topics, such as conservation. 4. Each bird species will be demystified 48 hours after publication. If you have bird images, video or mp3 files that you'd like to share with a large and appreciate audience, feel free to email them to me for consideration.GrrlScientistguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Alien planets: otherwordly joys The planet now known as Gliese 581 g is a reminder of the extraordinary rewards of astronomyThe rocky planet freshly identified in orbit around the star Gliese 581 could indeed be a potential home for life, but nobody should contemplate relocation just yet. At speeds possible with rocket technology, a voyage to Gliese 581, in the constellation Libra, would take about 200,000 years. As a home away from a home, it won't work. But the planet now known as Gliese 581 g is a reminder of the extraordinary rewards of astronomy.Cosmological science begins with the Copernican principle that there is nothing special about the solar system. Four centuries after Copernicus, this principle permitted a chain of observation, experiment and deduction that within half a human lifetime confirmed that the universe began with a big bang 13.7bn years ago. Robotic missions to Mars, Venus, Jupiter and Saturn showed that if life could begin on Earth, then it could surely happen on any planet of a similar fabric and mass, orbiting a similar star in a zone not too hot and not too cold for liquid water. Giant telescopes counted the stars: 100bn or more in this galaxy, one of 100bn galaxies. But the solar system appeared to be alone of its kind. The first extra-solar planet – or exoplanet – was identified in 1995: a kind of hot Jupiter, circling close to the star 51 Pegasi 50 light years away. Since then, astronomers have found 490 exoplanets but "seen" none of them.A planet is a ball of gas and dust dancing in a star's gravitational embrace. Gravity is a two-way thing and 51 Pegasi b was spotted from flickers of movement in the star that could only be explained by an invisible mass in orbit around it. Since then, researchers have confirmed the existence of exoplanets from rhythmic changes in starlight as an orbiting object moves across the face of the star, but that, too, is hardly a direct sighting. It took 11 years of observation and analysis to demonstrate that at least six planets orbit Gliese 581, and that one of them is a terrestrial-type planet in the so-called Goldilocks zone. Last year a purpose-built planet-spotter began the search for Earth-like planets as they transit across the faces of their parent stars. If there are other habitable planets, could they be inhabited? And if they are not inhabited, then could there be something very special indeed about Earth, and its citizens?The Gliese 581 team say: "If the local stellar neighbourhood is a representative sample of the galaxy as a whole, our Milky Way could be teeming with potentially habitable planets." The next step is to devise instruments that can take a closer look, perhaps for distant planetary atmospheres that contain oxygen and methane, the telltale signature of life as we know it. Our Earth-like neighbour 20 light years away is not the climax of a search. It is just a beginning.AstronomySpaceguardian.co.uk © Guardian News & Media Limited 2010 | Use of this content is subject to our Terms & Conditions | More Feeds guardian.co.uk |
Dead animals are Exhibit A in Gulf investigation By PHUONG LE 2010-10-14T21:38:33ZNEW ORLEANS (AP) -- Dead birds are wrapped in foil or paper, then sealed in plastic bags to avoid cross contamination. Dolphin tissue samples and dead sea turtles are kept in locked freezers. Field notebooks are collected and secured.... hosted.ap.org |
Unrelenting Pakistan's cycle of natural disasters bbc.co.uk |