Stories tagged comet

Who knows all the things that the new year will hold? But scientists looking to the skies are anxiously awaiting the appearance of a newly discovered comet which could be brighter than the moon. Predictions are that Comet ISON will be visible without the aid binoculars or telescope from early November to early January 2014. The comet will also pass fairly close, astronomically speaking, to Mars this year, giving the Mars rover something else to look at. Read more about Comet ISON here.

Oct
26
2011

Trajectory of comet Elenin
Trajectory of comet EleninCourtesy NASA/JPL-Caltech
Below is a news release from NASA/JPL about a comet that is going through some difficult times. NASA is sort of harsh in this release, imho, and really does not take the comet's feelings into account. Take a gander to see what I mean. Even the title is a little severe.

NASA Says Comet Elenin Gone and Should Be Forgotten

Comet Elenin is no more.

Latest indications are this relatively small comet has broken into even smaller, even less significant, chunks of dust and ice. This trail of piffling particles will remain on the same path as the original comet, completing its unexceptional swing through the inner solar system this fall.

"Elenin did as new comets passing close by the sun do about two percent of the time: It broke apart," said Don Yeomans of NASA's Near-Earth Object Program Office in Pasadena, Calif. "Elenin's remnants will also act as other broken-up comets act. They will trail along in a debris cloud that will follow a well-understood path out of the inner solar system. After that, we won't see the scraps of comet Elenin around these parts for almost 12 millennia."

Twelve millennia may be a long time to Earthlings, but for those frozen inhabitants of the outer solar system who make this commute, a dozen millennia give or take is a walk in the celestial park. Comet Elenin came as close as 45 million miles (72 million kilometers) to the sun, but it arrived from the outer solar system's Oort Cloud, which is so far away its outer edge is about a third of the way to the nearest star other than our sun.

For those broken up over the breakup of what was formerly about 1.2 miles (two kilometers) of uninspiring dust and ice, remember what Yeomans said about comets coming close to the sun – they fall apart about two percent of the time.

"Comets are made up of ice, rock, dust and organic compounds and can be several miles in diameter, but they are fragile and loosely held together like dust balls," said Yeomans. "So it doesn't take much to get a comet to disintegrate, and with comets, once they break up, there is no hope of reconciliation."

Comet Elenin first came to light last December, when sunlight reflecting off the small comet was detected by Russian astronomer Leonid Elenin of Lyubertsy, Russia. Also known by its astronomical name, C/2010 X1, Elenin somehow quickly became something of a "cause célèbre" for a few Internet bloggers, who proclaimed this minor comet could/would/should be responsible for causing any number of disasters to befall our planet.

Internet posts began appearing, many with nebulous, hearsay observations and speculations about earthquakes and other disasters being due to Elenin’s gravitational effects upon Earth. NASA’s response to such wild speculations was then in turn speculated to be an attempt to hide the truth.

"I cannot begin to guess why this little comet became such a big Internet sensation," said Yeomans. "The scientific reality is this modest-sized icy dirtball's influence upon our planet is so incredibly miniscule that my subcompact automobile exerts a greater gravitational influence on Earth than the comet ever would. That includes the date it came closest to Earth (Oct. 16), when the comet’s remnants got no closer than about 22 million miles (35.4 million kilometers)."

Yeomans knows that while Elenin may be gone, there will always be Internet rumors that will attempt to conjure up some form of interplanetary bogeyman out of Elenin, or some equally obscure and scientifically uninteresting near-Earth object. Thinking of ways to make himself any more clear about the insignificance of this matter is somewhat challenging for a scientist who has dedicated his life to observing asteroids and comets and discovering their true nature and effects on our solar system.

"Perhaps a little homage to a classic Monty Python dead parrot sketch is in order," said Yeomans. "Comet Elenin has rung down the curtain and joined the choir invisible. This is an ex-comet."
NASA detects, tracks and characterizes asteroids and comets passing relatively close to Earth using both ground- and space-based telescopes. The Near-Earth Object Observations Program, commonly called "Spaceguard," discovers these objects, characterizes the physical nature of a subset of them, and predicts their paths to determine if any could be potentially hazardous to our planet. There are no known credible threats to date.

Its like the person writing this had a personal vendetta against this poor comet. Though the Monty Python reference at the end helps lighten the mood, the overall dismissive tone of this news release is a bit sad.

Poor Elenin and its remaining "piffling particles".

Oct
17
2011

.Jose A. y Bonilla's 1883 photgraph
Jose A. y Bonilla's 1883 photgraphCourtesy Wikimedia

In August, 1883, Mexican astronomer Jose A. y Bonilla observed several objects passing in front of the solar disc. These objects were reported as being surrounded by a mist, looked dark against the solar disc, but bright outside of the disc. He took a photograph and published his findings in the magazine L'Astronomie in 1886. This photograph has had many interpretations, ranging from a flock of birds passing between the observer and the sun to the first photographic documentation of a UFO.

Recently, researchers from the Universidad Autonoma de Mexico have come up with an alternate explanation. Hector Javier Durand Manterola, Maria de la Paz Ramos Lara, and Guadalupe Cordero hypothesize that what Bonilla observed in 1883 was a highly fragmented comet, in an approach almost flush to the surface of the Earth. According to their calculations, the distance from the Earth's surface to the objects was between 538 km (334.3 miles) and 8,062 km (5009.5 miles), and the mass of the object before fragmentation was between 0.002 and 8.19 times the mass of Halley's Comet. Fragmentation of comets has been observed recently, as in the case of the comet Schwassmann-Wachmann 3, which fragmented in 1995/1996, 2001, and 2006, as shown here.Schwassmann-Wachmann 3 (2006)
Schwassmann-Wachmann 3 (2006)Courtesy NASA
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However, the report's claims have been questioned. A comet breaking up so close to earth should have resulted in a meteor shower, and no astronomers detected one.

Report: Interpretation of the observations made in 1883 in Zacatecas (Mexico): A fragmented Comet that nearly hits the Earth

Dec
08
2009

Poop with flies: you always manage to find a few of these guys on the pile.
Poop with flies: you always manage to find a few of these guys on the pile.Courtesy PKmousie
Poop. Poop. Poop. Poop. There. Have I got your attention? Of course, who can resist a story on poop? It is such a widely discussed topic with a vast array of monikers. Probably not a decent topic of conversation for invited guests or the dinner table, but it does get its chat time. Despite the disgust that it truly is, there is a curious fascination with the whole matter. It can tell you about your health, especially if you have the runs. It can tell you if you’ve been chewing your food well, or if you need to lay off the cheese. If you are a proper biologist, you’ve probably bent down and touched it or even broke it up to examine what passed. Certain scientists, such as Scatologists pursue the study of scat (poop) as a means to tell us more about a certain animal’s habits. If by the Fates, a poo survives intact and becomes old enough to fossilize, then we would call it a coprolite. Coprolites have been recovered from dinosaurs, ancient whales, fish, and prehistoric mammals to name a few.Coprolite: one very old poo
Coprolite: one very old pooCourtesy AlishaV

Recent news from BBC detailed a story about scientists studying the ancient droppings from mammoths. Well sort of. The researchers were examining mud deposits from a lake for fungal spores that are produced in large herbivore dung (mammoth poo). Their research concludes that the extra large mammals of the recent past experienced a slow and steady decline starting about 15,000 years ago. This flies in the face of the current prevailing theory, that an asteroid impact about 12,900 years ago caused global upheaval, world spread wildfire, and then abrupt extinction of the mega mammals. The asteroid theory had already been under assault by lack of evidence in soil samples. Samples taken all over the continent in soil cores extracted from peat bogs and lake bottoms.
Mammoth: artistic re-creation
Mammoth: artistic re-creationCourtesy ecstaticist
Was early man really responsible for the start of the downfall of the mammoth? I think undoubtedly we had a hand in their fate, but the answer is most likely multifaceted. Taking a closer look at the dung heaps of the past may well continue to give us a better picture of paleohistory. Just watch where you step!

mammoth dung story

mammoth comet story

Nice story on a recent find of a baby mammoth"

General Mammoth info
http://www.museum.state.il.us/exhibits/larson/mammuthus.html
http://www.ucmp.berkeley.edu/mammal/mammoth/about_mammoths.html

Each week, CNN posts a collection of space images. This week, you can see the green comet Lulin, thousands of satellites orbiting Earth, and some photos from the Hubble Space Telescope.

Making what is believed to be its first pass through our solar system, Comet Lulin will be passing by Earth tonight at its closest point to us on its celestial voyage. Full details are here from National Geographic. Despite its close tracking tonight to our planet, about 38 million miles, you'll still need to use a telescope or binoculars to see it. As a new comet, Lulin has just started to burn the frozen chemicals that make up its composition on this pass around the sun, giving astronomers a rare chance to see what happens with a brand-new comet


Stardust Capsule: Image courtesy NASA.
From Lawrence Livermore National Laboratory:

Contrary to expectations for a small icy body, much of the comet dust returned by the Stardust mission formed very close to the young sun and was altered from the solar system’s early materials.

When the Stardust mission returned to Earth with samples from the comet Wild 2 in 2006, scientists knew the material would provide new clues about the formation of our solar system, but they didn’t know exactly how.

New research by scientists at Lawrence Livermore National Laboratory and collaborators reveals that, in addition to containing material that formed very close to the young sun, the dust from Wild 2 also is missing ingredients that would be expected in comet dust. Surprisingly, the Wild 2 comet sample better resembles a meteorite from the asteroid belt rather than an ancient, unaltered comet.

More on this story here.

More on the Stardust/Wild 2 mission here.

Nov
05
2007

Attention seeking comet: Comet Holmes photographed in 6" reflector telescope, 100x, 2 seconds, 400iso on Oct 25,2007, 7:10 UT (from Minneapolis, Minnesota)  Image courtesy Tom Ruen via Wikipedia.
Attention seeking comet: Comet Holmes photographed in 6" reflector telescope, 100x, 2 seconds, 400iso on Oct 25,2007, 7:10 UT (from Minneapolis, Minnesota) Image courtesy Tom Ruen via Wikipedia.
So, in the category of “we don’t know why this is happening but you should check it out” a comet that used to be so dim you needed a telescope to see it has become suddenly so much brighter it can now be seen with the naked eye.

Comet 17P Holmes, visible to northern hemisphere residents, is practically demanding attention by suddenly becoming just over half a million times brighter than it was just a few hours previously. The comet can be found in the constellation Perseus and is visible for most of the night, and thanks to daylight savings time is easier to see earlier in the day. It resembles a fuzzy, yellowish star.

The comet was originally discovered by British astronomer Edwin Holmes on November 6, 1892. The crazy thing is, he discovered it because of a similar incident to what is happening now, it suddenly became so much brighter it was easily observable. Practically 115 years to the day! Also crazy is that if you think about its size (no more than 2 miles in diameter) and its distance from the Earth, it has to really be glowing to be seen!

In 1892 the comet faded after a few weeks, and we should expect a similar fading to happen in this instance – so get out there now to see this once in a lifetime opportunity! (Binoculars will help.)

We've previously posted about Comet McNaught over Minneapolis. NASA's STEREO satellite, which is normally used to look at our sun, caught some awesome pics of this super close comet. Watch the movie of Comet McNaught.

Dec
15
2006

Hot comet: Results of research from the Stardust comet particle retrieval mission are showing that the surface of comet Wild2 is composed of materials from the inner portions of our solar system. It used to be believed that comets were composed of matter from the outer regions of our solar system.
Hot comet: Results of research from the Stardust comet particle retrieval mission are showing that the surface of comet Wild2 is composed of materials from the inner portions of our solar system. It used to be believed that comets were composed of matter from the outer regions of our solar system.
What makes up a comet?

Scientists are starting to find out as they dig into the samples of a comet collected through the recent Stardust space mission. And they’re finding out that a comet is made up a of lot more than space’s intergalactic dust bunnies, which used to be the original concept of comet formation..

Testing on the samples from the Comet Wild2 are showing that it is made up of hot particles from the inner solar system that drifted out to the colder ranges of the our solar system around Pluto’s orbit. Prior to these finding, astronomers thought that comets were made up from tiny, cold space particles from regions of space further out of our solar system that were drifting into our system.

After doing the recent tests on Wild2’s comet dust, researchers are now estimated that around ten percent of a comet’s make up could have come from our inner solar system near the sun. How those particles have ended up as part of a comet are still a mystery to researchers, however. It may be the result of the chaotic activity at the forming of the solar system when “hot” inner solar systems were blasted out into the outer reaches of space.

And scientists are finding out that not all comets are created equal. Dust from Wild2 is very different from that of Tempel1, which was studied by NASA’s Deep Impact mission. On that mission, NASA last July crashed a probe into a comet and analyzed the dust and ice that spewed out from the crash. No surface materials were analyzed.

With Wild2, the Stardust mission sent a capsule around the sun and then swooping past Wild2 to scrape up thousands of tiny samples of comet surface materials. That capsule returned to Earth in January for scientists to begin analyzing the make up of the comet’s surface.

Some of the minerals found in the Wild2 dust are “high-temperature” minerals that were likely formed in the hottest portions of our solar system.