Rare meteor shower to shed light on dangerous comets

[Azur]

_http://space.newscientist.com/article/dn12443-rare-meteor-shower-to-shed-light-on-dangerous-comets.html

A rare meteor shower predicted to hit Earth on 1 September should give astronomers only their second chance to study an ancient comet's crust. It could also help them develop a warning system against an otherwise insidious threat – a comet aimed at Earth from the dark fringes of the solar system.

September's shower, called the alpha Aurigids, has only been seen three times before, in 1935, 1986 and 1994. The reason for this elusiveness is the shower's unusual origin.

Most meteor showers are caused by short-period comets, dirty iceballs that loop around the inner solar system on orbits lasting less than 200 years, shedding debris each time they approach the Sun's heat. This debris builds up into a broad band along the comet's orbit. Every year, when we pass through, it burns up in the atmosphere and appears as shooting stars.

The Aurigids come from a comet that takes 2000 years to orbit the Sun. With such infrequent visits, Comet Kiess can't build up a broad dust band; it only generates a narrow trail of debris each time.

The showers happen when Earth passes through one of these dust trails in particular, which was thrown off by the comet in 83 BC. "It is only a very narrow trail, and it is only once in a while that it crosses Earth's path," says Peter Jenniskens of NASA's Ames Research Center in Moffett Field, California, US.

He thinks the gravity of Jupiter and Saturn controls the path of the dust trail, waving it around like a garden hose, occasionally aiming it at Earth. Along with his colleague Jérémie Vaubaillon at Caltech, US, Jenniskens has calculated that the hose should be pointed at us again this year.
Hard crust

Several teams of astronomers will be watching the shower, both from the ground and from two aircraft following the Earth's shadow.

They are hoping to see fragments of the ancient crust of Comet Kiess. For 4.5 billion years before some gravitational accident nudged it towards the inner solar system, Kiess was drifting among a vast swarm of icy bodies called the Oort cloud lying far beyond the planets.

All that time, high-energy particles called cosmic rays bombarded the comet, and astronomers suspect that created a hard crust by blasting out some of its more volatile substances.

Only once before have astronomers knowingly seen a shower from a long-period comet, when Jenniskens predicted an appearance of the alpha Monocerotids in 1995. They penetrated unusually far into the atmosphere, suggesting that they were made of relatively tough material, perhaps from such a cosmic-ray-produced crust.

This time, astronomers will be looking at the spectral signature of evaporating meteors to test this theory. "Now we are better prepared, we can do more in-depth studies to understand the properties of the material," Jenniskens told New Scientist.
Contribute observations

He also wants to know whether meteor showers such as this could warn of planetary peril. At present, astronomers can only spot a long-period comet a few years before it arrives in the inner solar system, leaving little time to deflect it if it were pointed right at Earth.

But if it had visited the inner solar system before, the resulting meteor shower might be used to trace the comet's orbit and get a much earlier warning. The size and number of Aurigid meteors will tell the researchers how debris has spread along the orbit and how these showers evolve.

They are keen for amateurs to contribute their observations. "We're interested to know what is the brightest, biggest Aurigid," says Jenniskens. "Somebody is going to capture that, and it's probably not going to be us."

The best view of the meteors will be from the west coast of North America, before dawn on 1 September. Based on past showers, there should be up to 200 bright meteors visible per hour, and they may have an unusual blue-green colour.

The shower probably won't return for at least 50 years, according to Jenniskens' calculations. "It's a once in a lifetime event."

 

[Rick]

In fact if you read the article carefully, the comet last appeared in 83 BC which is closer to a 2100 year periodicity, half the 4200 year cycle mentioned in this SOTT article:

Harvey Weiss, an archaeologist at Yale U. wrote an article in 2002 called Environmental Disaster and the Archaeology of Human Response.

The earliest Holocene abrupt climate changes occurred at 12,800, 8200, 5200, and 4200 B.P. The 4200 B.P. abrupt climate change is especially well documented across West Asia, Central Asia, Africa, and parts of the New World. Limnological and speleothem radiometric dates situate the beginning of this event at ca. 3,800 radiocarbon years before 1950 (3.8 ka bp) or ca. 2200 B.C.

Now, half of 4200 is 2100 and in terms of harmonics, half periods can be as significant as full periods (so can quarter, eighths, etc.) depending on what they resonate with. This event could very well be a part of the 4200 year cycle and may in fact be the warning bell for what's about to happen. Since Jupiter and Saturn can alter the course of the comet debris the exact period will fluctuate.

Here's another thought. Earthfiles.com has an August 18th countdown message from the crop circles:

August 13, 2007 Stanton St. Bernard, Wiltshire, England - In my July 23, 2007, Earthfiles report entitled, "070707 East Field Wheat Formation: Viewer Comments," there is a section written by an Australian scientist who requests anonymity. The Earthfiles report shares his "Lunar Cycle Count Down to August 18, 2007" analysis of the 150 circles in the East Field that were discovered shortly after a bright flash of light around 3 AM on July 7, 2007. See: 072307 Earthfiles.

On August 6, he emailed about the 9-fold wheat geometry reported August 4, 2007, below the Pewsey White Horse, Pewsey, Wiltshire, England. See: 080707 Earthfiles.

Today, the Australian scientist emailed:

"Stanton St. Bernard of August 12: six days left until a significant, if unknown, event on August 18, 2007.

"A new crop picture from Stanton St. Bernard shows the ancient Mayan symbol for number '6,' as a long bar drawn just below a filled circle (many thanks to Michelle Jennings and Heather Horning for their quick and astute observations).

"Furthermore, on close inspection, one can see that its 'filled circle' contains 12 small and 1 central swirl for a total of 13 mini-swirls:

"Taken together, both observations lead one to believe that those crop artists are trying to tell us about '6 days' from their ancient 13-month calendar (based on motions of Venus and the Sun), where any month contained 20 days, and any year contained 13 x 20 = 260 days.

"The 'long bar' in that same crop picture is skewed with respect to a nearby tramline by approximately 10 degrees. Such a small, but precise angle might be intended to represent the small angular fraction of '6 days' within any complete 260-day Mayan year as (6 / 260) x 360 = 8.3 degrees. But I cannot be sure from current photographs: Would someone like to measure in the field?

"Why would they show us the ancient Mayan symbol for '6 days' right now, on the particular date of August 12, 2007?

"In the context of other pictures from 2007, this new message seems to represent the continuation of some countdown until a significant, if unknown, event on August 18. That same date was implied symbolically at East Field on July 7, in terms of 'lunar cycles;' at Sugar Hill on July 31 in terms of 'cube sundials;' and at Pewsey on August 4 in terms of a 'solar-lunar calendar.'

"The Sun and Venus are moving towards an inferior conjunction on August 18, thereby ending their current 260-day Sun-Venus calendar, and beginning another. So they could be trying to tell us about that, or maybe something else entirely?

"In the context of other pictures from 2004 or 2005, this new message seems to represent the continuation of Mayan Sunstone messages from Silbury 2004 and Wayland's Smithy 2005. The latter also coded for a near-future date of August 16-19, 2007, in terms of an ancient 52-year Sun and Venus calendar.

Graphic number overlay by Australian scientist on mini-swirls inside circle of wheat "dot and bar" formation reported on August 12, 2007, Stanton St. Bernard, Wiltshire, England.

"So far, not many individual crop pictures have shown both 'date' and 'event nature' in the same field, except for:

- Wayland's Smithy 2005 >>> date = August 16-19, 2007 >>> event nature = Mayan symbol for earthquake.

- Wayland's Smithy 2006 >>> date = mid-August 2007 >>> event nature = astronomical rays from space.

East Field 2007 >>> date = August 18, 2007 >>> event nature = disappearance of the Moon (i.e. cloud cover). East Field was documented on camera, as forming immediately after a bright flash of light above the field.


The most recent 2007 pictures have shown either one or the other, but not both:

Sugar Hill of July 31 >>> date = 18 days left

Pewsey of August 4 >>> date = 32-34% phase in the next lunar cycle (i.e. August 18-19)

Westwoods of August 9 >>> event nature = slippage of Earth's gravity well (i.e. tectonic plates)

Stanton of August 12 >>> date = 6 days left

Probably two more crop formations to go (toward August 18 countdown)?"

Take it all with a grain of salt. But then there's Terence McKenna's Time Wave Zero graph. Scroll down and notice the peak on the zoomed in plot - around 8/18/2007.

 

[Laura]

Gee, 8-18-2007 is my youngest daughter's 18th birthday... I plan to be making a gluten free "Death by Chocolate" cake on that day... So, if anything weird happens, at least we'll have chocolate!

 

[Rick]

Gee, 8-18-2007 is my youngest daughter's 18th birthday... I plan to be making a gluten free "Death by Chocolate" cake on that day... So, if anything weird happens, at least we'll have chocolate!

Well, I'll be traveling to NYC, home of the best chocolate babka on the planet. If my usual source is out then indeed it would be a cataclysmic event.