In “Building block of life found on comet” (Tue Aug 18, 2009, 9:37am EDT), Steve Gorman writes:
LOS ANGELES (Reuters) – The amino acid glycine, a fundamental building block of proteins, has been found in a comet for the first time, bolstering the theory that raw ingredients of life arrived on Earth from outer space, scientists said on Monday.
Microscopic traces of glycine were discovered in a sample of particles retrieved from the tail of comet Wild 2 by the NASA spacecraft Stardust deep in the solar system some 242 million miles (390 million km) from Earth, in January 2004
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[Astrobiologist Jamie Elsila of NASA's Goddard Space Flight Center in Greenbelt, Maryland] presented the findings, accepted for publication in the journal Meteoritics and Planetary Science, to a meeting of the American Chemical Society in Washington, D.C., this week.
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Glycine and other amino acids have been found in a number of meteorites before, most notably one that landed near the town of Murchison, Australia in 1969, Elsila said.
(Editing by Anthony Boadle)
© Thomson Reuters 2009 All rights reserved
In “Cosmic Coincidence,” Spaceweather.com says in a newsletter alert (as forwarded to me by a stargazer):
COSMIC COINCIDENCE: What are the odds? On Tuesday, Feb. 24th, Saturn and Comet Lulin will converge in the constellation Leo only 2 degrees apart. At the same time, Comet Lulin will be making its closest approach to Earth–the comet at its best!– while four of Saturn’s moons transit the disk of the ringed planet in view of backyard telescopes. Oh, and the Moon will be New, providing dark skies for anyone who wishes to see the show.
The best time to look is around 1 a.m. Tuesday morning (your local time) when the planet-comet combo ascend high in the southern sky. To the unaided eye, Comet Lulin looks like a faint patch of gas floating next to golden Saturn. Point your backyard telescope at that patch and you will see a lovely green comet with a double tail.
Visit http://spaceweather.com for full coverage including photos, sky maps, and a live webcast.
Geographic Notes: Comet Lulin is visible from all parts of the globe–all longitudes and both hemispheres. Directions are reversed in the southern hemisphere; there the comet is located in the northern sky around 1 am. Saturn is globally visible, too, but the special quadruple transit of Saturn’s moons starting around 3 a.m. PST on Feb. 24th is visible only to observers around the Pacific Rim. Details may be found here: http://science.nasa.gov/headlines/y2009/19feb_quadrupletransit.htm
Just an FYI and a “heads up.” I’m interested in seeing the phenomenon, but I’ll be sleeping…
In “Unusual Green Comet Set to Pass Earth,” the AP’s Seth Borenstein says:
WASHINGTON (Feb. 18) – An odd, greenish backward-flying comet is zipping by Earth this month, as it takes its only trip toward the sun from the farthest edges of the solar system. The comet is called Lulin, and there’s a chance it can be seen with the naked eye — far from city lights, astronomers say. But you’ll most likely need a telescope, or at least binoculars, to spot it.
The best opportunity is just before dawn one-third of the way up the southern sky. It should be near Saturn and two bright stars, Spica and Regula.
On Monday [2-23-09] at 10:43 p.m. EST, it will be 38 million miles from Earth, the closest it will ever get, according to Donald Yeomans, manager of NASA’s Near Earth Object program.
Robert Roy Britt, over at Space.com, says in Saturday Night Special:
If skies are clear Saturday, go out at sunset and look for the giant moon rising in the east. It will be the biggest and brightest one of 2009, sure to wow even seasoned observers.
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But the orbit is not a perfect circle. One portion is about 31,000 miles (50,000 km) closer to our planet than the farthest part, so the moon’s apparent size in the sky changes. Saturday night (Jan. 10) the moon will be at perigee, the closest point to us on this orbit.
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The Elements of Astronomy by Simon Newcomb appears to be a good introductory book to astronomy. You can see chapter 2 of the book at the Website of the physics department of CSBSJU or you can download a PDF of the entire book on the Internet Archive for free. The book was printed in 1900 and is now, from what I have read, out of copyright. Some parts of the book might be out of date, but in many respects the book is not: our solar system and the causes of its motion remain the same. Elements has some concise, effective explanations and diagrams.
Here is a diagram used in the explanation of the seasons:
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