Sentences with phrase «impact by a comet»

Similarly, there are myriad ways that planets can lose their atmospheres, through stripping by the solar wind, baking by the sun's radiation or catastrophic impacts by comets or asteroids.

Not exact matches

If there was a huge meteor impact in the indian ocean by a comet, it would create a humongous tsunami that would sweep miles inland....

If it is in danger of being destroyed by impact with a comet, or something of that sort, there is very little the church can do about it.

The meteorite is made of volcanic rock, and the presence of water in it suggests that crustal rocks on Mars interacted with surface water that was delivered by volcanic activity, near - surface reservoirs or by impacting comets, Agee says.

That's because the higher speed of comets and the high volatility of their constituents would create giant plumes on impact, so more of the iridium would escape into space, compared with impacts by rocky asteroids.

If sunlight must penetrate the dust covering a comet's water ice in order to warm it and produce jets, Sunshine says the Deep Impact findings suggest the ices on such dormant comets may not have run out but merely become sealed — by layers of debris, for example.

Earth and the other planets of our solar system suffer occasional impacts when comets are disturbed from their orbits around the sun by the gravity of nearby stars and gas clouds.

Old assumptions about comets are faltering as results emerge from data collected by the Deep Impact spacecraft in July 2005, when the probe's impactor detached from the mother ship and crashed into the comet at 37,000 kilometres (23,000 miles) per hour.

Seen in seismic - reflection profiles, and in gravity and magnetic surveys, it has traits that are consistent with impact craters, which are caused by collisions with asteroids and comets.

«Some of the most interesting sites will be those that offer fresh material — perhaps exposed by an impact, a crack or plume activity like comets have — and those with diverse material,» said Keiko Nakamura - Messenger, OSIRIS - REx sample site scientist and the deputy lead for curation at NASA's Johnson Space Center in Houston.

Because the gas would have remained frozen within the comet's interior unless exposed by the impact, that suggests the probe did penetrate some sort of icy layer — but perhaps one much different from what astronomers originally predicted.

The glass itself, one large polished piece of which has a prominent place in a necklace that belonged to Egyptian pharaoh Tutankhamen, has been dated to 28.5 million years and has long been thought to be the result of a meteorite impact or an airburst caused by a comet breaking up in Earth's atmosphere.

Observers around the world saw Jupiter whacked by impacts on three occasions, including the dramatic multiple beating it took in 1994 by the comet Shoemaker - Levy 9.

Chunks of the moon and Mars (blasted free by other impacts on those bodies) and comets can also make their way here.

«It is believed that the Earth was initially dry, but our research strongly supports the view that the oceans we have today were created as a result of impacts by water - rich comets or asteroids.»

Prior to impact, Tempel 1 displayed the same streaming dust as any other comet, pushed back from the cometary body by the sun's radiation.

The shape and size of these chevrons suggest that they might have been formed by waves emanating from the impact of a comet slamming into the deep ocean off Madagascar.

«These stories are all exactly what you would expect from the survivors of a celestial impact,» Masse says, leafing through 2,000 - year - old drawings by Chinese astronomers that show comets of all shapes and sizes.

Additionally, Chumak caught a rare gossamer tail and disconnection event created by solar wind impacting the comet.

Last year, researchers found that in conditions mimicking those sparked by a comet or meteorite impact, intense heat and pressure converted formamide (which forms when hydrogen cyanide reacts with water) and other simple substances into the four information - bearing nucleobases in RNA, a likely genetic precursor to DNA.

On average, material blasted across Mercury's surface by relatively recent impacts of comets, asteroids, and other small bodies reflects only two - thirds as much light as freshly excavated material on the moon, previous studies have shown.

For more than 30 years, scientists have argued about a controversial hypothesis relating to periodic mass extinctions and impact craters — caused by comet and asteroid showers — on Earth.

The cratering record on the moon provides a proxy for similar impacts by interplanetary debris such as comets and asteroids on Earth, the effects of which have largely been erased by billions of years of erosion and geologic activity.

Some of those materials, he adds, were most plausibly delivered by comets impacting the moon.

While the origin of life remains mysterious, scientists are finding more and more evidence that material created in space and delivered to Earth by comet and meteor impacts could have given a boost to the start of life.

They reasoned that without continual renewal, the surfaces of such bodies should have become densely covered with craters as a result of impacts by meteorites and comets over the 4.5 billion years that they have existed.

The Deep Impact team were not only delighted by the success of the impact, but also by the survival of the flyby spacecraft after it was spattered by debris from the comet's tail, orImpact team were not only delighted by the success of the impact, but also by the survival of the flyby spacecraft after it was spattered by debris from the comet's tail, orimpact, but also by the survival of the flyby spacecraft after it was spattered by debris from the comet's tail, or coma.

Those results set the age boundary for the oldest terrains on Mercury to be contemporary with the so - called Late Heavy Bombardment (LHB), a period of intense asteroid and comet impacts recorded in lunar and asteroidal rocks and by the numerous craters on the Moon, Earth, and Mars, as well as Mercury.

The ice has been attributed to comet and meteor impacts, but it is possible some of this ice could have come from the water released by eruption of lunar magmas.

Giant planet interiors are inaccessible to direct study from above, but oscillations excited by asteroid and comet impact can generate waves that are potentially observable.

My point here is we are entering a current of thinking, developed by a few scientists all over the world, reconsidering the time of humans in terms of multiple comet impacts, not all of them yet known.

The leading hypothesis is that it was delivered by water - rich comet or asteroid impacts.

MAVEN's instruments sent back data on the gases and dust released by Siding Spring, while others are currently assessing the impact of the comet's tail on the Martian atmosphere.

The global science community still isn't entirely sure what caused the repeated cycles — there may have been larger oceans in the northern hemisphere that powered a hydrological cycle (evaporation, condensation, precipitation), or shorter cycles could've been caused by volcanic activity or asteroid / comet impacts.

Smaller terrestrial planets lose most of their atmospheres because of this accretion, but the lost gases can be replaced by outgassing from the mantle and from the subsequent impact of comets.

Since a 2005 visit by NASA's Deep Impact spacecraft, the short - period comet has completed more than one complete orbit around the Sun and approached the inner Solar System as close as the orbital distance of Mars.

This 1.25 - mile - or 2 - kilometer - long, «peanut - shaped» comet nucleus was the fifth visited by Human spacecraft, which in this case was NASA's re-purposed Deep Impact probe.

Formed by the impact of a large asteroid or comet, Caloris is one of the largest, and possibly one of the youngest, basins in the Solar System.

During its approach, Rosetta has trained its navcams and OSIRIS camera at the comet, which sent back dramatic pictures of Churyumov — Gerasimenko; revealing it to be craggier and sharper edged than the asteroids and moons previously explored that had been worn down by billions of years of meteor impacts.

Today (2008), after the Deep Impact space mission to comet Tempel 1, the best estimate for the amount of water on a comet is 38 % by mass.

The «YDB» event, which occurred circa 10,770 BC, is thought to have been caused by the impacts or air - bursts of several comets, resulting in massive shockwaves and firestorms sweeping across continents, initiating a 1200 year - long epoch of terminal environmental change and catastrophic faunal extinction, effectively wiping all but traces of early civilizations from the historical record.This book explores the forbidden and deeply profound secrets of a magnificent lost civilization, revealing knowledge long concealed in myth and legend.

Ideas that commonly surface include perturbations to the earth's orbit by other planets, disruptions of ocean currents, the rise and fall of greenhouse gases, heat reflection by snow, continental drift, comet impacts, Genesis floods, volcanoes, and slow changes in the irradiance of the sun.

Chesapeake Bay is the site of an ancient impact crater, caused by a comet or meteor.