Astronomy @ MindSay 
2003 ub313
We have just started a New Year according to our common Gregorian calendar. The earth just completed going around the sun once. We have just seen 366 sunrises, since the last new Year's Day. There goes a story many of us have not heard of, or have forgotten. Early mathematicians who invented the science of "geometry" decided to divide a circle into 360 degrees. The word geometry itself is inspired from geo -- earth, metry-- measurements. They saw the earth going around the sun in some 360 days (according to their crude and primitive measurements).
Although, later this was proved wrong, we continue to stick to the 360 degrees rule of circles (each degree reminds us of one day in earth's annual excursion), a big blunder which the world has accepted since ages. So, every time we celebrate New Year, we must think of this historic blunder which we made several centuries ago.
Subsequent generations of mathematicians, corrected all this, giving rise to a bewildering variety of calendars. A good collection of calendar related information can be found at ::: http://www.hermetic.ch/cal_stud.htm
The science of geometry grew into the science of astronomy (now we start looking at the stars). We have now come to the stage when we can actually hope to visit these celestial bodies. All this started with a faulty premise of 360 degrees to a circle.
partha
plus tomorrow I start my formal set times for tours at the garden. come on down !!
Makes me wish I had a telescope or at least a good pair of binoculars.
Best Meteor Shower of 2007 Peaks Dec. 13
What could be the best meteor display of the year will reach its peak on the night of Dec.13-14.
Here is what astronomers David Levy and Stephen Edberg have written of the annual Geminid Meteor Shower: "If you have not seen a mighty Geminid fireball arcing gracefully across an expanse of sky, then you have not seen a meteor."
The Geminids get their name from the constellation of Gemini, the Twins, because the meteors appear to emanate from a spot in the sky near the bright star Castor in Gemini.
Also in Gemini this month is the planet Mars, nearing a close approach to the Earth later this month, and shining brilliantly with yellow-orange hue. To be sure, Mars is certain to attract the attention of prospective Geminid watchers this upcoming week.
Reliable shower
The Geminid Meteors are usually the most satisfying of all the annual showers, even surpassing the famous Perseids of August.
Studies of past find the "Gems" have a reputation for being rich both in slow, bright, graceful meteors and fireballs as well as faint meteors, with relatively fewer objects of medium brightness.
They are of medium speed, encountering Earth at 22 miles per second (35 kps). They are bright and white, but unlike the Perseids, they leave few visible trails or streaks. They are four times denser than most other meteors, and have been observed to form jagged or divided paths.
Geminids also stand apart from the other meteor showers in that they seem to have been spawned not by a comet, but by 3200 Phaethon, an Earth-crossing asteroid. Then again, the Geminids may be comet debris after all, for some astronomers consider Phaethon to really be the dead nucleus of a burned-out comet that somehow got trapped into an unusually tight orbit. Interestingly, on December 10, Phaethon will be passing about 11 million miles (18 million kilometers) from Earth, its closest approach since its discovery in 1983.
The prospects for this year
The Geminids perform excellently in any year, but British meteor astronomer, Alastair McBeath, has categorized 2007 as a "great year."
Last year's display was hindered somewhat by the moon, two days past last quarter phase. But this year, the moon will be at new phase on Dec. 9. On the peak night, the moon will be a fat crescent, in the south-southwest at dusk and setting soon after 8 p.m. That means that the sky will be dark and moonless for the balance of the night, making for perfect viewing conditions for the shower.
According to McBeath, the Geminids are predicted to reach peak activity on Dec. 14 at 16:45 GMT. That means those places from central Asia eastwards across the Pacific Ocean to Alaska are in the best position to catch the very crest of the shower, when the rates conceivably could exceed 120 per hour.
"But," he adds, "maximum rates persist at only marginally reduced levels for some 6 to 10 hours around the biggest ones, so other places (such as North America) should enjoy some fine Geminid activity as well.
Indeed, under normal conditions on the night of maximum activity, with ideal dark-sky conditions, at least 60 to 120 Geminid meteors can be expected to burst across the sky every hour on the average (Light pollution greatly cuts the numbers).
The Earth moves quickly through this meteor stream producing a somewhat broad, lopsided activity profile. Rates increase steadily for two or three days before maximum, reaching roughly above a quarter of its peak strength, then drop off more sharply afterward. Late Geminids, however, tend to be especially bright. Renegade forerunners and late stragglers might be seen for a week or more before and after maximum.
What to do
Generally speaking, depending on your location, Gemini begins to come up above the east-northeast horizon right around the time evening twilight is coming to an end. So you might catch sight of a few early Geminids as soon as the sky gets dark.
There is a fair chance of perhaps catching sight of some "Earth-grazing" meteors. Earth grazers are long, bright shooting stars that streak overhead from a point near to even just below the horizon. Such meteors are so distinctive because they follow long paths nearly parallel to our atmosphere.
The Geminids begin to appear noticeably more numerous in the hours after 10 p.m. local time, because the shower's radiant is already fairly high in the eastern sky by then. The best views, however, come around 2 a.m., when their radiant point will be passing very nearly overhead.
The higher a shower's radiant, the more meteors it produces all over the sky.
But keep this in mind: At this time of year, meteor watching can be a long, cold business. You wait and you wait for meteors to appear. When they don't appear right away, and if you're cold and uncomfortable, you're not going to be looking for meteors for very long! The late Henry Neely (1878-1963), who for many years served as a lecturer at New York's Hayden Planetarium, once had this to say about watching for the Geminids: "Take the advice of a man whose teeth have chattered on many a winter's night – wrap up much more warmly than you think is necessary!"
Hot cocoa or coffee can take the edge off the chill, as well as provide a slight stimulus. It's even better if you can observe with friends. That way, you can keep each other awake, as well as cover more sky. Give your eyes time to dark-adapt before starting.
Bundle up and good luck!
A thought provoking sequel to What If . . .
Astronomers find system with five planets
By Maggie Fox,
Health and Science Editor
55 Cancri
WASHINGTON (Reuters) - NASA scientists said they discovered a fifth planet orbiting a star outside our own solar system and say the discovery suggests there are many solar systems that are, just like our own, packed with planets. The new planet is much bigger than Earth, but is a similar distance away from its sun, a star known as 55 Cancri, the astronomers said on Tuesday. Four planets had already been seen around the star, but the discovery marks the first time as many as five planets have been found orbiting a solar system outside our own with its eight planets, said Debra Fischer, an astronomer at San Francisco State University. Life could conceivably live on the surface of a moon that might be orbiting the new planet, but such a moon would be far too small to detect using current methods, the astronomers said. "The star is very much like our own sun. It has about the same mass and is about the same age as our sun," Fischer told reporters. "It's a system that appears to be packed with planets."
It took the researchers 18 years of careful, painstaking study to find the five planets, which they found by measuring tiny wobbles in the star's orbit. The first planet discovered took 14 years to make one orbit. They said 55 Cancri is 41 light-years away in the constellation Cancer, a light-year being the distance light travels in one year -- about 5.8 trillion miles. The newly discovered planet has a mass about 45 times that of Earth and may resemble Saturn, the astronomers said.
HARBORING LIFE?
It is the fourth planet out from the star and completes one orbit every 260 days -- a similar orbit to that of Venus. "It would be a little bit warmer than the Earth but not very much," said Jonathan Lunine, a planetary scientist at the University of Arizona. The planet is 72 million miles from its star -- closer than the Earth's 93 million miles, but the star is a little cooler than our own sun. "If there were a moon around this new planet ... it would have a rocky surface, so water on it in principle could puddle into lakes and oceans," said Geoff Marcy, an astronomer at the University of California, Berkeley. But the moon would have to carry a lot of mass to hold the water, he said. Water is, of course, key to life.
"This discovery of the first-ever quintuple planetary system has me jumping out of my socks," Marcy added. "We now know that our sun and its family of planets is not unusual." Marcy and other astronomers strongly believe that many stars are hosts to solar systems similar to our own. But small objects such as planets are very hard to detect. Technology that would allow scientists to detect planets as small as Earth is decades away, the scientists agreed.
The researchers have been looking at 2,000 nearby stars using the Lick Observatory near San Jose, California, and the W.M. Keck Observatory in Mauna Kea, Hawaii. They have posted images of what the planets may look like on the Internet at http://www.nasa.gov/audience/formedia/telecon-20071106/. The inner four planets of 55 Cancri are all closer to the star than Earth is to the sun. The closest, about the mass of Uranus, zips around the star in just under three days at a distance of 3.5 million miles.
Animation Descriptions
1. Animation Part 1: Journey to a Star Rich with Planets
In the first part of an artist's animation, we take a journey from Earth's surface to the newest member of the 55 Cancri planetary system.
2. Fifty-five Cancri in the Night Sky
This wide-angle photograph of the night sky shows the location of 55 Cancri, a star where astronomers have found a record-breaking five planets.
3. Animation Part 2: Journey to a Star Rich with Planets
In the second part of the artist's animation, we fly out to see 55 Cancri's habitable zone (green) and the orbits of its planets compared to our own.
4. Our Solar System's Cousin?
This artist's concept illustrates two planetary systems - 55 Cancri (top) and our own.
5. Plentiful Planetary System
This artist's concept shows four of the five planets that orbit 55 Cancri, a star much like our own.
What are the possibilities of there being life other than our own in other star systems in other galaxy's in the endless universe ? Anything is possible. Wouldn't it be interesting to connect with other life in far off places ? To learn or share our thoughts, ideas, technology or belief's. To find answers to our most sought after questions and concerns. To find solutions to our most difficult problems. What would we do if we encountered such life ? How would we react ? Are we open, understanding and civilized enough to be able to accept life from another world ?
Until such an event occurs, the question still lingers in my mind . . .
What If . . . ?
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