Total Pageviews

Saturday, 22 December 2007 - The Other Bright Comet of 2007/2008 - Observing Blog - The Other Bright Comet of 2007/2008
OBSERVING BLOG by Tony Flanders

The Other Bright Comet of 2007/2008

With Comet Holmes still blazing away nearly as bright as ever, it's easy to forget that another bright comet is crossing the far-northern sky.

Comet 8P/Tuttle will be approaching its maximum brightness as it crosses Cassiopeia in the next-to-last week of December. Click above for a printable PDF chart.
S&T Illustration
Although no match for Holmes, Comet 8P/Tuttle is now visible through 10×50 binoculars under dark skies. A telescope may be required in the suburbs.

To help you find the comet, we have prepared two printable finder charts in PDF format. Comet positions on both charts are shown for 0 h in Universal Time — equal to 7 p.m. on the preceding date in Eastern Standard Time.

Click here to see the comet's path before Dec. 25.

Click here for a chart covering late December and all of January.

S&T Illustration
The comet is predicted to peak in brightness around the New Year, as shown at right. And recent magnitude estimates indicate that the predictions are pretty much on target.

So far, the comet appears to be a modest-sized, medium-faint circular blob. But comets are famously unpredictable, as Holmes has just demonstrated in the most dramatic fashion. So Comet Tuttle bears watching too, despite its current rather bland appearance. Nobody can predict when or if it will sprout a tail — or even undergo a dramatic outburst like Comet Holmes.

Tuttle moves across the sky at a fairly sedate pace in early December, but it picks up speed as it makes its closest approach the Earth — just 23.5 million miles away — on New Year's Day. Despite the full Moon, the comet should be a fairly easy target by the time it crosses the W of Cassiopeia from December 20-25. And around 0 h UT on December 31st (7 p.m. Dec. 30 EST), the comet passes through the outer edge of Messier 33, the Triangulum Galaxy. (Think photo-op!)

The comet moves south quite rapidly during January, passing through Pisces, Cetus, Fornax, and then into the southern reaches of Eridanus. It will become a challenging target for northern observers around the middle of the month, when it's swallowed in the glow of the first-quarter Moon.

For more information on Comet Tuttle, see the January issue of Sky & Telescope. And don't miss the sidebar on the checkered career of Horace Tuttle: comet hunter, war hero, and embezzler.
Posted by Tony Flanders, December 12, 2007

Monday, 17 December 2007

Astronomy and Earth Science: Winter solstice and Christmas

Christmas marks the birth of Christ, and it is celebrated by Christians around the world. But this holiday has close ties to an older festival known as the "Unconquered Sun." The impact this Pagan tradition had on how Christmas was celebrated is one of the ways in which The Christian tradition changed as it developed through the ages.

The winter solstice is the time when the Sun reaches its southernmost rising and setting points in the northern hemisphere and the Suns apex at noon is at its lowest point of the year. The days are shortest and the nights are longest.

December 25th was the date of the winter solstice in the calendar Julius Caesar devised for Rome in 46BC. Today the winter solstice usually occurs on December 21st. Although Caesar used a 365 1/4 day year, a year is actually a little shorter, and this made the solstice occur a little earlier over the years. There was a discrepancy of 1 day in 128 years.

The pagans celebrated the winter solstice as the Unconquered Sun. After this day, the Sun would begin to stay in the sky longer each day, and there would be less cold, and less night; the Sun would win the battle of night and day. There would be feasts, evergreens would be brought into the house to be decorated and lighted with candles to pay tribute to the Sun.

There is nothing in the Christian Bible to specify the day of Christmas. Prior to the fourth century, Christs birth had been associated with Three Kings Day on January 6. But the pagans and the newly converted were being a major problem to the church because they were still celebrating the Unconquered Sun. Nothing the church did or said made a difference; the winter solstice was just too important a festival.

What the Christians did in this dilemma, was execute a move seen over and over in history. If you cant defeat them, and refuse to join them, at least make it appear that you defeated them. Sometime between AD 354 and 360 a few decades after Emperor Constantine?s conversion to Christianity, the celebration of Christmas was shifted to the day of the Unconquered Sun. But the tradition of the Sun god lived on a long time.

The Romans got the idea of the sun god from the Syrians. Their Sun god, Deus Sol Invictus, became the chief god of the Roman State under Aurelian. The Fathers of the Church however, insisted that Christ was the true Sun God, and said that any celebrations for the Sun, were really in celebration of Christ.

Both the Sun worshipers and the Christians saw the solstice/birthday as a transition from darkness to light. Christ conquered the darkness, as did the Sun. Since the theme was similar, the traditions of one blended well with the other.

People have still carried over these traditions, though their earlier pagan roots have mostly long been forgotten. "Christmas" trees are still brought into the house. Colored lights and candles light the darkness. The Yule Log is lit.

In some Christian churches, on Christmas eve, the electric lights are dimmed. In the semi- darkness, the Christmas story is told, and near the end, a single candle is lit. It signifies the movement out of the darkness.

Yeah-always light a candle in the yule log at Christmas-cw..


Thursday, 13 December 2007

The local Weather for Kessingland....

The local weather for Kessingland-a fantastic site run by Adam:

Monday, 10 December 2007

The Christmas 'Star' an omen or nova-or something else?

The star of Bethlehem was not a star, so what was it?
That astronomical puzzle is among the questions posed by a planetarium show put on this month by the York County Astronomical Society at the York Learning Center in North York.
The 25-minute, pre-recorded show prompts stargazers to imagine the sky as it might have looked the night the shepherds kept watch over their flocks in the hills surrounding Bethlehem at the time of Jesus' birth (thought to be between 10 and 2 B.C.).
For centuries, historians, astronomers, curious Christians and others have speculated on what manner of natural heavenly light led the wise men to the manger in Bethlehem.
Some scholars have argued the story, found in the second chapter of Matthew, was not meant to be read as fact.
Others, including many Christians, believe the star actually appeared over historic Bethlehem, leading the wise men (Magi) from the east.
After seeing the YCAS show Saturday, 24-year-old Denny Daugherty, of Dover, said he found the proposed theories intriguing-
"It's just another way to appreciate God's creation," he said.
So what could account for the Christmas star?
It has been identified as a comet, Halley's Comet, an exploding star, meteors, or the planets and how they sometimes move into alignment - a Mars/Jupiter/Saturn conjunction, a triple conjunction of Jupiter and Saturn and the occultation of Jupiter by Venus.
The script of the North York show was written in the 1970s by a pair of amateur astronomers and educators, George Reed and Gerald Mallon. It leaves the impression that a conjunction of planets - what would appear from Earth to be a gathering of planets in the night sky - is the most favored scientific explanation for the star.
Astronomers have calculated that in 7 B.C., Jupiter and Saturn appeared to come very close to one another, making the planets appear to merge (Saturn was, of course, millions of miles deeper in space). Mars moved in a year later and created a grouping of Jupiter-Saturn-Mars.
The timing works out as historians estimate that Jesus was born a few years before the end of the B.C. era, so it's possible the planetary conjunction was the beacon that drew the Magi to Bethlehem.
"But there's no confirmation that's definitely it," said Mike Smith, senior astronomy educator at the North Museum at Franklin & Marshall College in Lancaster.
"It might be an intriguing theory, but it's made of too much speculation."
William Kreiger, assistant professor of earth science at York College, listed simpler explanation: Perhaps the Bethlehem star was a twinkling planet.
"You've got to take into context what the understanding of stars and the heavens and the earth in general 2,000 years ago," Kreiger said.
At that time, people sometimes mistook planets for very bright stars, he explained.
But Kreiger's recollection is that scientists' most oft-mentioned claim is an exploding star (nova or supernova), which flares up thousands of times brighter than a regular star and would have lasted months before fading (long enough for the Magi to get from Persia to Jerusalem).
However, a supernova would have left debris that astronomers would have noticed, said Todd Ullery, a YCAS member from Shrewsbury Township.
Other theories, such as Uranus and ball lightning, have been largely discredited:
Because meteors recur throughout the year, they wouldn't have been seen as a remarkable phenomenon in the night sky, Smith said.
Comets are rarer and not always visible with the naked eye. In antiquity, they were often looked upon as an evil omen, so the Magi probably wouldn't have deemed a comet divinely inspired, Smith said.
And a comet doesn't fit the fleeting star reference in Matthew: A comet would not move in a southerly direction or stop over a certain city or house.
Greg Carey, a New Testament scholar at Lancaster Theological Seminary, interprets the star as a literary device - one used to explain why Jesus' birth matters.
"In the ancient world people frequently claimed that the arrival of a new king or emperor was signaled by a new star," he said by e-mail.
"Matthew is probably appealing to that tradition in his story, saying that astrological portents attended Jesus' birth, just as they do his death later in the Gospel."
An article in Sky & Telescope magazine this month by student Aaron Adair suggests any search for an astronomical star of Bethlehem is fatally flawed - a misguided attempt to force science on a faith-based story.
He compares the astronomical theories behind the fabled star and concludes none are plausible when examined against the description of the star's behavior in Matthew's original Greek.
"Essentially, today's authors and planetarium directors proposing an astronomical star are two centuries behind in biblical scholarship," wrote Adair, a show presenter at Abrams Planetarium and a math, physics and astronomy student at Michigan State University.
"A believer can posit that the star was a local miracle that the Magi alone could see. A historian can only regard the tale as fictional or at least not investigable. In either case, astronomy is irrelevant."

The Star of Bethelehem:

3 Wise Men following the Star:


Wednesday, 5 December 2007

Christmas Astrononomy....

The Winter Solstice Sunrise (this year on Saturday 22nd December 06.08 Hours)

Comets at Christmas and the warm fireside

Pluto and Charon the ice worlds

The Christmas Comet