Source of zodiac glow identified
New research identifies Jupiter Family comets as the primary source of the zodiacal cloud's eerie glow, contradicting previous theories that pointed to asteroid dust.
Comets
Articles tagged with Comets
NASA's Rosetta 'Alice' spectrometer reveals Earth's ultraviolet fingerprint in Earth flyby
The European Space Agency's comet orbiter spacecraft Rosetta successfully tested the performance of its ultraviolet spectrometer Alice during a recent Earth flyby, revealing the Earth's unique ultraviolet spectral emission signature.
Kansas scientists probe mysterious possible comet strikes on Earth
Researchers at the University of Kansas have discovered a potential signature of nitrate and ammonia that can be found in ice cores corresponding to suspected impacts. This finding could help scientists better understand the frequency of comet strikes on Earth, providing valuable insights for future predictions.
'Ultra-primitive' particles found in comet dust
Researchers found ultra-primitive material with higher abundances of presolar grains, indicating a diverse processing of materials in different comets. This discovery allows for comparison of cosmic processes on a microscopic scale four-and-a-half billion years ago.
NASA researchers make first discovery of life's building block in comet
NASA researchers have discovered glycine, an amino acid used by living organisms to make proteins, in samples of comet Wild 2. The discovery supports the theory that some of life's ingredients formed in space and were delivered to Earth long ago.
Evidence of liquid water in comets reveals possible origin of life
A new study published in the International Journal of Astrobiology claims that comets contained vast oceans of liquid water during their formation, providing ideal conditions for primitive bacteria to grow and multiply. The study's findings support the theory of cometary panspermia, which suggests that life was introduced to Earth by c...
Crashing comets not likely the cause of Earth's mass extinctions
New University of Washington research suggests comets unlikely cause mass extinctions, contradicting long-held belief. The study shows that Jupiter and Saturn's gravitational fields protect Earth from most comets, limiting potential impact.
Space shuttle science shows how 1908 Tunguska explosion was caused by a comet
New Cornell University research links 1908 Tunguska explosion to comet entry, supported by NASA space shuttle exhaust plume. The study reveals a possible connection between the two events through noctilucent clouds, which are the Earth's highest clouds forming at high altitudes and in extremely cold temperatures.
Contrary to recent hypothesis, 'chevrons' are not evidence of megatsunamis
Contrary to recent hypothesis, geologists argue that chevrons are not evidence of megatsunamis caused by asteroids or comets. Instead, they propose that similar formations can be explained by wind-blown deposits, supported by the presence of volcanic ash in similar locations.
We owe it all to comets
Researchers found that comets delivered necessary ingredients for life in the Earth's ancient primordial soup. The chemical composition of comets allowed them to kickstart life by providing stable proportions of noble gases.
NASA's Swift satellite comet tally highlighted
Comets are analyzed using Swift's Ultraviolet/Optical Telescope, which separates wavelengths of ultraviolet light to study gases surrounding the icy bodies. Cometary X-ray emission is also detected, providing insights into the process of charge exchange between solar ions and comet gases.
NASA's Swift spies Comet Lulin
Comet Lulin is releasing a great amount of gas, making it an ideal target for X-ray observations. Swift's UVOT detects hydroxyl molecules, revealing a cloud spanning nearly 250,000 miles, while the XRT sees X-rays from the comet's atomic cloud.
NASA's Swift looks to comets for a cool view
Swift's Ultraviolet/Optical Telescope (UVOT) observes the chemical composition of comet atmospheres, while its X-Ray Telescope (XRT) studies gas and solar wind interactions. This research offers clues about comets' origins and the solar system.
Comet particles provide glimpse of solar system's birth spasms
Comet particles from Wild 2 provide a glimpse of the solar system's early convulsions, flinging primordial material out into the cold regions. The particles contain minerals formed at high temperatures, suggesting transport from the inner to outer solar system.
Comet dust reveals unexpected mixing of solar system
Researchers analyzed oxygen isotope compositions of comet Wild 2's halo crystals, finding signatures similar to asteroids and the sun. This suggests heat-processed particles were transported outward in the young solar system, complicating theories on its early history.
Combination treatment for early rheumatoid arthritis induces remission and prevents progression
A combination treatment with methotrexate and etanercept improves remission rates by 50% and radiographic non-progression by 21% compared to methotrexate alone. The treatment also increases the ability of patients to remain in employment, with significant implications for employers and society.
Did the solar system 'bounce' finish the dinosaurs?
A Cardiff University study suggests that the sun's movement through the Milky Way causes comets to collide with Earth every 35-40 million years, coinciding with mass extinctions like the dinosaurs' extinction. This cosmic 'bounce' effect may also have helped life spread by dispersing micro-organisms into space.
Stardust comet dust resembles asteroid materials
New research reveals that comet Wild 2's sample is missing ingredients expected in cometary IDPs and resembles chondritic meteorites from the asteroid belt. The high-speed capture of Stardust particles may have altered the material.
U of M physicist reads the history of the solar system in grains of comet dust
A University of Minnesota physicist analyzed comet Wild-2 dust, finding it formed close to the infant sun and bombarded by intense radiation before being flung out. The discovery sheds light on the solar system's early stages and potential impact on Earth's atmosphere.
Stardust formed close to sun
The analysis of noble gases in Stardust samples indicates that some particles match a special type of carbonaceous material found in meteorites and must have spent time near the sun. The study suggests an alternative mechanism for grain incorporation into comets, contradicting earlier formation theories.
Deep Impact 'celebrates' New Year's Eve with Earth flyby
The Deep Impact spacecraft is using its flyby of Earth to calibrate its instruments for the EPOXI mission, which will study comet Hartley 2. The team made observations of the moon to test the spacecraft's pointing and commanding systems.
Deep Impact extended mission heads for comet Hartley 2
The EPOXI mission will use the Deep Impact spacecraft to search for Earth-sized planets around five stars and conduct an extended flyby of Comet Hartley 2, studying its surface and composition. This new mission aims to better understand how solar systems form and evolve.
New CU-Boulder study detects first known belt of moonlets in Saturn's rings
A narrow belt of moonlets as large as football stadiums has been discovered in Saturn's outermost ring, likely resulting from a larger moon being shattered by an asteroid or comet. The discovery supports the theory that Saturn's rings were initially created through a collisional cascade.
NRL instrument on NASA satellite sees solar hurricane detach comet tail
Scientists at NRL capture first images of a comet colliding with a solar hurricane, revealing the detachment of the comet's tail due to coronal mass ejection. The event is triggered by magnetic reconnection, releasing energy and detaching the plasma tail.
NASA satellite sees solar hurricane detach comet tail
A NASA satellite has captured the first-ever images of a comet's plasma tail detaching from Encke's comet due to a coronal mass ejection. The event was triggered by magnetic reconnection between the comet's and solar wind fields, releasing a burst of energy that detached the tail.
Extraterrestrial impact likely source of sudden Ice Age extinctions
Scientists at Brown University propose that an asteroid impact triggered catastrophic climate change, leading to the mass extinction of megafauna such as wooly mammoths. The theory is based on evidence of nanodiamonds and other extraterrestrial particles found in sediment samples from archeological sites.
Research team says extraterrestrial impact to blame for Ice Age extinctions
A team of international researchers suggests that a comet or low-density object caused the mass extinctions at the end of the Ice Age, proposing a 'mini nuclear winter' triggered by a 10-million-megaton detonation. This impact would have destabilized a vast ice sheet, leading to rapid cooling and subsequent climate change.
SourceNorthern Arizona University·JournalProceedings of the National Academy of Sciences·DateSep 24, 2007
Comet probes reveal evidence of origin of life, scientists claim
New findings from comet probes confirm the existence of organic molecules and clay particles that could have formed early life. The Cardiff University team argues that comets' liquid interiors provide a suitable environment for life's emergence.
Unlocking the frozen secrets of comet Wild 2
Researchers analyze comet Wild 2 samples, finding evidence of material formed at both cold and hot temperatures, and unusual organic molecules with oxygen and nitrogen content. The discovery raises questions about how these fragile materials survived capture and formed in the early solar system.
ESRF helps reveal the origin of the Solar System
Researchers analyze cometary material from Stardust spacecraft, improving understanding of early solar system chemistry and mixing. ESRF's X-ray beams help determine element distribution without damaging particles.
Far-out findings -- New analysis suggests planets were formed from a giant mix
Researchers analyzed dust fragments from Comet Wild-2 to gain insights into the early Solar System's formation. The study found diverse mineral compositions in the comet dust, indicating extensive mixing before planet formation, and evidence of surprising variety in cometary composition.
Stardust particles tell story about birth of solar system
The analysis of Stardust particles from comet Wild 2 has revealed clues about the birth of our solar system, challenging some basic theories. The particles contain osbornite, a mineral that forms at high temperatures, indicating a volatile and dynamic environment during the solar system's infancy.
Stardust findings override some commonly held astronomy beliefs
Scientists have discovered material in comets that originated from the sun's inner solar system, defying a popular notion. The Stardust mission found particles with extreme properties, including one made of calcium-aluminum inclusion and another composed of magnesium olivine.
UC Berkeley researchers developed techniques to pluck comet dust from Stardust collectors
Researchers at UC Berkeley have developed techniques to pluck comet dust from the aerogel collectors used by NASA's Stardust spacecraft. The extracted samples reveal a diverse and unexpected composition of materials, including calcium/aluminum-rich inclusions similar to those found in meteorites.
'Cosmic freezer' yields unique discovery
Researchers at Washington University in St. Louis analyze comet samples and discover a unique result: the presence of 'real' stardust particles older than the sun. This finding provides key insights into the composition and origin of comets, shedding light on their role in the solar system's formation.
A window on the environment from Tahoe to the ocean
Researchers at UC Davis are developing a virtual library of data from hundreds of environmental sensors to study the interconnectedness of air, water, land, and living things in California. This 'God's-eye view' will help understand how climate change affects the state, including precipitation patterns, wildfires, and ocean upwelling.
Pre-life molecules present in comets
Researchers from the University of Michigan and Harvard-Smithsonian Center for Astrophysics discovered atomic nitrogen in interstellar gas clouds, suggesting pre-life molecules may be present in comets. This finding sheds new light on the early conditions that led to life on Earth.
Mysterious carbon excess found in infant solar system
Researchers have discovered a surprising amount of carbon in the gas surrounding a young star, Beta Pictoris. The findings may indicate that asteroids and comets in this system could contain large amounts of organic material, which could have delivered building blocks of life to early Earth.
Highlights of American Chemical Society meeting in Atlanta, March 26-30
Research on grape seed extract's potential to lower blood pressure, discovery of new elements, and studies on prostate cancer were among the topics presented at the ACS meeting. The conference also featured discussions on improving America's scientific competitiveness and food safety.
Carnegie scientists fine-tuning methods for Stardust analysis
Researchers are analyzing Stardust samples to study the structure and chemistry of cometary material, providing clues about the solar system's history. The team is using advanced spectroscopic techniques to identify organic compounds and isotopic signatures in the ancient grains.
Comet from coldest spot in solar system has material from hottest places
Astronomers discover high-temperature minerals in comet Wild 2, challenging the formation of crystalline materials. The Stardust mission brings back samples from the coldest spot in the solar system, providing clues about the origin of these materials.
Comet dust from NASA mission under analysis
Comet dust samples collected by the Stardust mission are being studied to determine their mineral composition, providing valuable insights into the formation of the solar system. The samples, which consist of ice, dust, and rock, were analyzed using electron microscopes and other techniques.
NASA's 'Deep Impact' team reports first evidence of cometary ice
The study provides key insights into the composition of comets, with three pockets of thin ice detected on Tempel 1. The surface ice appears to have been exposed over time through geologically active jets, revealing an abundance of organic matter and water.
UW astronomer hits cosmic paydirt with Stardust
A UW astronomer has successfully collected a record-breaking amount of cosmic dust from comet Wild 2, which dates back to the formation of the solar system 4.6 billion years ago. The aerogel collector, which greatly reduced impact stress on particles, revealed tracks of larger particles visible from several feet away.
Stardust parachutes to soft landing in Utah with dust samples from comet
The Stardust spacecraft successfully recovered comet dust samples from Wild 2, which are believed to hold evidence about the formation of the sun and solar system. The samples will be studied using powerful instruments, including electron microscopes and nuclear accelerators.
Virtual microscope allows public to search for dust grains in Stardust detectors
Researchers at UC Berkeley will invite Internet users to help them search for interstellar dust grains captured by NASA's Stardust spacecraft. The 'virtual microscope' technology allows anyone with an internet connection to scan images of aerogel for tracks left by speeding dust, in hopes of discovering grains from distant stars.
Stardust nears end of epic journey; Researchers await its treasure
The Stardust spacecraft is returning to Earth after a 2.88 billion-mile journey, carrying samples of comet Wild 2 and interstellar dust. The samples are expected to provide key information on the formation of the solar system 4.6 billion years ago.
Are comets more like 'icy dust balls' or 'dirty snowballs'?
Researchers observed the impact of a copper projectile on Comet Tempel 1, finding it released approximately 4,500 tonnes of water vapor. The comet's surface was composed of icy grains that sublimed in sunlight, producing a bright tail. These findings suggest comets are more like 'icy dust balls' than previously thought 'dirty snowballs'.
Evidence for more dust than ice in comets
New findings from the Rosetta spacecraft suggest comets are composed primarily of dust held together by ice, contradicting the long-held 'dirty snowball' hypothesis. Cometary nuclei like Comet 9P/Tempel 1 exhibit dynamic and volatile properties, with impacts triggering outbursts of dust and gas.
NASA's Deep Impact team releases first snapshot of Comet Tempel 1
The Deep Impact mission revealed several dozen impact craters on Comet Tempel 1, with a powdery layer tens of meters deep. The comet's surface is composed of a fine-grained, loosely glued layer of organic powder and ice, sparking new questions about its composition and the formation of the solar system.
Scientists use X-rays to measure how deep 'Deep Impact' was
The 'Deep Impact' collision released tens of thousands of tons of material, enough to bury a football field under 30 feet of comet dust. Scientists are analyzing X-ray data to better understand the evaporation process on comets and their interaction with solar wind.
NASA's swift satellite offers a different view of the great comet collision
Swift detected a quick rise in ultraviolet light after the Deep Impact probe struck a hard surface on the comet, revealing secrets about the impact.
Hubble captures Deep Impact's collision with comet
NASA's Hubble Space Telescope captured dramatic images of comet 9P/Tempel 1 before and after a 820-pound projectile impact by the Deep Impact spacecraft. The collision caused a brilliant flash and increased the size of the inner cloud of dust and gas, which expanded outward in a fan shape at speeds of up to 1,200 miles per hour.
UCAR training helps forecasters predict rip currents
The new Web-based modules, developed by COMET, will acquaint forecasters with the physics behind rip currents and help them use wind and wave forecasts to produce outlooks of rip-current risk. The modules include animated depictions of rip-current evolution in three dimensions.
What's inside a comet? Brown geologist helps NASA find out
A Brown University geologist is part of a joint space mission to study a comet's composition. The Deep Impact mission will provide a first-ever look inside a comet when an impactor hits Tempel 1, helping scientists understand how comets shaped the solar system.
Spitzer space telescope reads solar system's 'Rosetta Stone'
Scientists have discovered minerals in comet dust similar to those found on Earth, providing insights into the solar system's formation. The Spitzer space telescope has captured detailed images of Comet Encke, helping researchers model how comets eject particles as they orbit the sun.
UA scientist on deep impact mission ready for spacecraft's launch
The Deep Impact mission aims to study the composition of Comet Tempel 1 by deploying a copper probe into its surface. The probe will capture images and spectra of the comet's interior, shedding light on the early solar system's formation.
Young stars poised for production of rocky planets
Researchers used VLT interferometer observations to study infrared spectra of dusty discs around three young stars, finding abundant crystalline silicate grains and processed dust near the star. This suggests that building blocks for Earth-like planets are present in circumstellar discs from the start.
UK astronomers scan the skies for threat from space
A team of British astronomers is tracking Near-Earth Objects (NEOs) using the Faulkes Telescope North and South in Hawaii and Australia. The UK Astrometry and Photometry Programme (UKAPP) provides crucial information to protect the Earth from potential asteroid impacts.
What is a comet made of?
Comet composition can be studied for the first time using a new technique, providing insights into the early solar system. Carbon disulfide has been detected in comet 122P/De Vico, with implications for understanding the origins of life.