|
| © Noriko Kita |
| A team of researchers including Takayuki Ushikubo, Noriko Kita, and John Valley of the University of Wisconsin-Madison has identified unexpected chemical and isotope signatures that challenge existing views about the formation and history of the solar system. |
Comets
Chemical clues from a comet's halo are challenging common views about the history and evolution of the solar system and showing it may be more mixed-up than previously thought.
The BBC and the National Geographic Channel are making a documentary based on the controversial theories of a Wollongong academic, who claims that meteorites hit the earth every 1000 years.
|
| ©Sylvia Liber |
| Professor Ted Bryant with the US film crew at Jones Beach. |
A new picture of the composition of comets is emerging with the help of 21st century technology available at Diamond, the UK's national synchrotron light source, in Oxfordshire.
Scientists already know that comets played a significant role in ensuring that conditions were right for life on Earth. Most of the icy, small planetary bodies that otherwise became comets went into forming the gas giant planets in the outer Solar System but some were ejected from the vicinity of the largest planets. Of these, a fraction ended up in the inner Solar System bringing water and biogenic elements of interest to Earth. Without this cometary transport, life on Earth may never have had a chance to start.
Now, scientists from the Space Research Centre at the University of Leicester have, for the first time, brought samples of the Comet Wild-2 to Diamond. In doing so, using Diamond's microfocus spectroscopy capabilities - bright and powerful X-rays with a beam size equivalent to one 25th of a human hair - they have discovered that the old model of comets as dusty iceballs is not the whole picture.
|
| ©NASA/JPL |
| Comet Wild 2. |
Scientists already know that comets played a significant role in ensuring that conditions were right for life on Earth. Most of the icy, small planetary bodies that otherwise became comets went into forming the gas giant planets in the outer Solar System but some were ejected from the vicinity of the largest planets. Of these, a fraction ended up in the inner Solar System bringing water and biogenic elements of interest to Earth. Without this cometary transport, life on Earth may never have had a chance to start.
Now, scientists from the Space Research Centre at the University of Leicester have, for the first time, brought samples of the Comet Wild-2 to Diamond. In doing so, using Diamond's microfocus spectroscopy capabilities - bright and powerful X-rays with a beam size equivalent to one 25th of a human hair - they have discovered that the old model of comets as dusty iceballs is not the whole picture.
An asteroid cruising through the solar system six years ago seemed just another silent ship sailing in the eternal darkness, until it flared up with the startling brightness of a comet's halo.
|
| ©space.com |
Halley's comet, which lights up Earth's sky every 75 years with its glowing tail, is a bit of a scientific mystery.
So far theories have been at a loss to explain how it acquired its extremely unusual backwards orbit, but the recent discovery of another odd comet orbiting farther out in the solar system may shed light on Halley's origins.
The newly-discovered comet 2008 KV42 circles the sun at a tilt of 104 degrees compared to the main plane in which most of the planets and asteroids travel. The newfound oddball also orbits in reverse compared to almost everything else. Scientists think it might represent an intermediate point between comets like Halley's and their progenitors in the far and totally uncharted reaches of the solar system.
Geneva - A Swiss amateur astronomer has discovered a new comet from an observatory in the western Jura district, the ATS news agency said Saturday.
Only five similar comets -- fragile clusters of dust, ice and carbon-based molecules believed to be primitive material left over from the building of our star system -- have been been documented from Switzerland since the 17th century.
The latest one to be discovered has a diameter of 20,000 kilometres (12,400 miles) and has been named Ory after Michel Ory who made the discovery, the report said.
Discovered from the Vicques Observatory in Jura, Ory spotted the comet overnight from Tuesday to Wednesday and again from Wednesday to Thursday.
The best sightings are expected in October and November, the report added.
Only five similar comets -- fragile clusters of dust, ice and carbon-based molecules believed to be primitive material left over from the building of our star system -- have been been documented from Switzerland since the 17th century.
The latest one to be discovered has a diameter of 20,000 kilometres (12,400 miles) and has been named Ory after Michel Ory who made the discovery, the report said.
Discovered from the Vicques Observatory in Jura, Ory spotted the comet overnight from Tuesday to Wednesday and again from Wednesday to Thursday.
The best sightings are expected in October and November, the report added.
Allen West's presentation August 8, 2008 to the Pecos Archeological Conference at the University of Northern Arizona's Cline Library Auditorium
Part 1:
Part 1:
Less than a week before the peak of the Leonids meteor shower, there is a slim chance that an astral display from a newly-discovered comet will be visible Thursday in the northern sky -- near the lower left star in the bowl of the Big Dipper.
Comet LINEAR, found in May by the Lincoln Near-Earth Asteroid Research team, made its closest pass to the sun on September 20.
Comet LINEAR, found in May by the Lincoln Near-Earth Asteroid Research team, made its closest pass to the sun on September 20.
A recently conducted study on diamonds and precious metals found in the eastern U.S. proposes that the minerals might have been transported through the air by a 3-mile wide comet that hit Canada during the last Ice Age.
It is clear to the researchers that diamonds, silver and gold found in Ohio and Indiana were transported there from Canada about 12,900 years ago, according to Live Science, but the question is how.
It is clear to the researchers that diamonds, silver and gold found in Ohio and Indiana were transported there from Canada about 12,900 years ago, according to Live Science, but the question is how.
Fireballs set half the planet ablaze, wiping out the mammoth and America's Stone Age hunters
Scientists will outline dramatic evidence this week that suggests a comet exploded over the Earth nearly 13,000 years ago, creating a hail of fireballs that set fire to most of the northern hemisphere.
Scientists will outline dramatic evidence this week that suggests a comet exploded over the Earth nearly 13,000 years ago, creating a hail of fireballs that set fire to most of the northern hemisphere.
