Clipmarks | invictus's Astronomy collection

'Hundreds of worlds' in Milky Way

Mon, 18 Feb 2008 01:52:48 GMT

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Scientists say there may be many more worlds in our solar system

Rocky planets, possibly with conditions suitable for life, may be more common than previously thought in our galaxy, a study has found.

New evidence suggests more than half the Sun-like stars in the Milky Way could have similar planetary systems.

There may also be hundreds of undiscovered worlds in outer parts of our Solar System, astronomers believe.

Future studies of such worlds will radically alter our understanding of how planets are formed, they say.

New findings about planets were presented at the American Association for the Advancement of Science (AAAS) in Boston.

Tags: astronomy, space, milky way, galaxies, life, science

Asteroid flyby today - no impact risk

Tue, 29 Jan 2008 12:27:52 GMT

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Clip Source: www.spaceweather.com

Asteroid 2007 TU24 is flying past Earth today. There's no danger of a collision, but the 250m-wide space rock is close enough (1.4 lunar distances) to photograph through backyard telescopes as it speeds through the constellation Cassiopeia glowing like a 10th magnitude star. NASA radars are monitoring the flyby and may produce new images of the rock by week's end. [ephemeris] [3D orbit]

Tags: astronomy, science, asteroids, space, solar system

Moon is younger and more Earth-like than thought

Thu, 20 Dec 2007 00:29:42 GMT

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Clip Source: space.newscientist.com

It's a good thing the Moon doesn't have any feelings to hurt. New research suggests it is actually 30 million years younger than anyone had thought, and that it is merely a 'chip off the old block' of Earth rather than being made up of the remnants of a Mars-sized body that slammed into Earth billions of years ago.

That violent impact was thought to have taken place 30 million years after the solar system began to condense from a disc of gas and dust 4.567 billion years ago. The event was thought to have melted the Earth, generating a magma ocean that covered the planet and allowed iron and other metals to sink to its centre, forming a core.

At the same time, the Moon was thought to have coalesced from a disc of molten debris blasted off the Earth and the Mars-sized interloper.

But new research led by Mathieu Touboul of the Swiss Federal Institute of Technology in Zurich suggests that picture is not so simple.

Tags: moon, earth, space, science

Close Encounter with Mars

Mon, 17 Dec 2007 23:56:56 GMT

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Clip Source: spaceweather.com

Ready your telescopes! On Tuesday evening, Dec. 18th, Mars makes its closest approach to Earth until the year 2016. At a distance of only 55 million miles, Mars outshines every star in the night sky (it is slightly brighter than Sirius) and draws attention to itself with its distinctive red color. Plus, it looks great through a backyard telescope:

Tags: astronomy, planets, backyard astronomy, mars, science

"Exploding Comet" Photo Gallery

Sun, 11 Nov 2007 17:20:07 GMT

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clipper's remarks: Many good shots of Comet 17P/Holmes, taken by backyard astronomers around the world.

Clip Source: spaceweather.com

Summary: Comet 17P/Holmes shocked astronomers on Oct. 24, 2007, with a spectacular eruption. In less than 24 hours, the 17th magnitude comet brightened by a factor of nearly a million becoming a naked-eye object in the evening sky. Look for a golden 2.5th magnitude fuzzball in the constellation Perseus after sunset.

Tags: astronomy, comets, comet holmes, images, photography

Exploding Comet update - New images

Mon, 29 Oct 2007 22:55:08 GMT

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Clip Source: spaceweather.com

Exploding Comet 17P/Holmes is now larger than Jupiter. Astronomer Eric Allen of Quebec's Observatoire du Cégep de Trois-Rivières combined images he captured on three consecutive nights (Oct. 25, 26 and 27) and placed them beside a picture of Jupiter scaled to the same distance as the comet:

The diaphanous and curiously spherical cloud surrounding the comet's core is now large enough to physically swallow the King of Planets!

And that's just for starters. The growing comet subtends an angle (4 arcminutes) as large as the Moon's Sea of Tranquillity. Last night in Higham Ferrers, England, Dave Eagle photographed "the Moon and Comet Holmes with the same setup to show how big this strange comet is."

Although the comet is not as bright as Jupiter or a lunar mare, it is visible to the unaided eye. Look north after sunset for a magnitude +2.5 fuzzball in the constellation Perseus: sky map.

Tags: astronomy, comets, exploding comet, images, science

Radio burst from space mystifies astronomers

Sat, 29 Sep 2007 01:08:42 GMT

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Clip Source: news.yahoo.com

Astronomers who stumbled upon a powerful burst of radio waves said on Thursday they had never seen anything like it before, and it could offer a new way to search for colliding stars or dying black holes.

They were searching for pulsars -- a type of rotating compacted neutron star that sends out rhythmic pulses of radiation -- when they spotted the giant radio signal.

It was extremely brief but very strong, and appears to have come from about 3 billion light-years away -- a light-year being the distance light travels in a year, or about 6 trillion miles.

"This burst appears to have originated from the distant universe and may have been produced by an exotic event such as the collision of two neutron stars or the death throes of an evaporating black hole," said Duncan Lorimer of West Virginia University and the National Radio Astronomy Observatory.

Tags: astronomy, pulsars, radio signals, science

Rare dead star found near Earth

Tue, 21 Aug 2007 00:22:55 GMT

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Clip Source: news.bbc.co.uk

Neutron stars form when massive stars exhaust their fuel

Astronomers have spotted a space oddity in Earth's neighbourhood - a dead star with some unusual characteristics.

The object, known as a neutron star, was studied using space telescopes and ground-based observatories.

But this one, located in the constellation Ursa Minor, seems to lack some key characteristics found in other neutron stars.

Details of the study, by a team of American and Canadian researchers, will appear in the Astrophysical Journal.

If confirmed, it would be only the eighth known "isolated neutron star" - meaning a neutron star that does not have an associated supernova remnant, binary companion, or radio pulsations.

Either Calvera is an unusual example of a known type of neutron star, or it is some new type of neutron star, the first of its kind

Robert Rutledge, McGill University

The object has been nicknamed Calvera, after the villain in the 1960s western film The Magnificent Seven.

Tags: space, neutron star, calvera, science

Colossal tail trails dying star

Wed, 15 Aug 2007 22:49:59 GMT

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clipper's remarks:

"The fact that Mira's tail only glows with ultraviolet light might explain why other telescopes have missed it."

Clip Source: news.bbc.co.uk

A distant star that hurtles through space at extraordinary speeds has a huge, comet-like tail trailing in its wake, astronomers say.

The appendage, which measures a colossal 13 light years in length, was spotted by Nasa's Galaxy Evolution Explorer (Galex) space telescope.

The researchers said that nothing like it had ever been spotted around a star.

They believe the star, known as Mira, will help them to study what happens as stars meet their demise.

Mira (also called Mira A) has captivated astronomers for more than 400 years.

It sits about 350 light-years from Earth in a constellation known as Cetus, and is accompanied in orbit by a smaller secondary star, called Mira B, forming a binary system.

Billions of years ago, Mira would have been much like our Sun, but as it now enters its death-throes it has swollen into a type of star known as a red giant.

Yet despite centuries of study, its spectacular tail had remained undetected.

Tags: astronomy, space, mira, cetus, binary stars, science

Celestial show begins this weekend

Fri, 10 Aug 2007 20:22:44 GMT

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Clip Source: news.bbc.co.uk

The annual Perseid meteor shower will reach its peak during the early hours of Monday, but it will be visible from Saturday night until Tuesday morning.

The celestial show will be most apparent in the north-eastern part of the sky near the Perseus constellation.

If the skies remain clear, it will offer stargazers the best opportunity for a few years to see the Perseids.

The shower this year coincides with a new Moon, providing sky watchers with the dark skies necessary for excellent observing conditions.

The best viewing conditions will be where the sky is clearest and darkest. However, meteors should be visible, to a lesser degree, in cities despite light pollution and smog.

Both hemispheres will receive good views but the prime locations will be Western Europe and North America.

As an added bonus, watchers should be able to see Mars, which will be in view as a bright red dot in the eastern sky after midnight.

Tags: astronomy, night sky, meteor shower, perseids, backyard astronomy

Saturn's ring mystery is solved

Fri, 03 Aug 2007 11:20:24 GMT

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Clip Source: news.bbc.co.uk

Saturn's ring mystery is solved

Cassini images of Saturn's G ring captures its single, bright arc

Scientists have made a significant step forward in understanding the dynamics of Saturn's magnificent and mysterious system of rings.

The behaviour of one ring in particular - the G ring - has baffled experts.

Its dust particles should ebb away because there are no nearby moons to hold them in place or replenish them.

But the Cassini probe has shed new light on the faint, narrow ring; showing that it interacts with a much more distant Saturnian satellite.

The work, published in Science, also unveiled the ring's odd structure.

The G ring is one of Saturn's outermost rings: it is more than 168,000km from the centre of the planet and more than 15,000km from the nearest moon.

"It's a dusty ring," explained Matthew Hedman, a research associate at Cornell University and lead author of the study. "Like the E ring and F ring, it is primarily composed of tiny grains of ice just a few microns across."

Tags: astronomy, space, planets, saturn

Astronomers claim galaxy record

Wed, 11 Jul 2007 22:03:10 GMT

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Clip Source: news.bbc.co.uk

Astronomers claim galaxy record

The detections were made at the Keck Observatory

Astronomers say they may have detected the light from some of the earliest stars to form in the Universe.

They have pictures of what appear to be very faint galaxies that shone more than 13 billion years ago, a mere 500 million years after the Big Bang.

The remarkable claim dramatically exceeds the current, broadly accepted record for the most distant detection.

The Caltech-led team behind the work recognises there will be sceptics but says it believes its data is strong.

It has published details in The Astrophysical Journal; and the group leader, Professor Richard Ellis, has been arguing the case at a conference in London, UK.

"We've had these galaxies for over a year and we have gone back to the telescope and revisited them, to prove their signals are robust," he explained.

Tags: astronomy, space, galaxies, big bang, astrophysics, science

Mars Tilt Shifted, Says Theory

Fri, 15 Jun 2007 15:38:15 GMT

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clipper's remarks: Scientists believe massive volcanic events forced a redistribution of mass at Mars' surface, causing its poles to shift.

Clip Source: dsc.discovery.com

Mars Tilt Shifted, Says Theory

Scientists firing the latest salvo of opinions over the mystery of Mars' water say they have new evidence to back the theory that a mighty ocean once washed over much of the Red Planet's surface.

The theory — derived from photos snapped by orbiters and geological and chemical data sent home by rovers Spirit and Opportunity — is that as much as a third of Mars' surface was once covered by water.

The cornerstone of this idea is that there are remarkable "shoreline" features visible in a ring thousands of miles long on the planet's northern hemisphere lowlands.

But there's a big problem: these intriguing features are at widely different altitudes, with elevation varying by several thousands of feet instead of all being at "sea level" as they should be.

Harvard University scientist Taylor Perron and colleagues say that there is a reason for this discrepancy.

Tags: space, mars, planets, solar system, science

"Night Shining Clouds" over Europe

Thu, 07 Jun 2007 19:21:36 GMT

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Clip Source: spaceweather.com

NLC ATTACK: Last night, a wide expanse of electric-blue noctilucent clouds (NLCs) appeared over Europe. "It was a beautiful display," says Martin McKenna of Maghera, N.Ireland. "Wonderful twisting bands and waves were begging for attention." Paul Evans of Larne, N. Ireland, snapped this picture:

Noctilucent clouds are a mystery. They were first reported in the 19th century after the eruption of super-volcano Krakatoa. In those days the clouds were confined mainly to high latitudes, but they have intensified and spread with sightings in recent years as far south as Colorado and Utah. What causes NLCs? A NASA spacecraft named AIM is in orbit right now on a mission to find out.

One thing is known: Summer is the season for NLCs. Sky watchers in Europe have seen hints of NLC activity in recent weeks, but "this is the finest display so far," says Evans. The cloud was approximately 25^o high x 100^o wide." Consider it official: NLC season has begun.

Tags: atmospheric sciences, clouds, nlc, science

Potentially habitable planet found

Wed, 25 Apr 2007 14:36:07 GMT

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Clip Source: news.yahoo.com

Potentially habitable planet found

WASHINGTON - For the first time astronomers have discovered a planet outside our solar system that is potentially habitable, with Earth-like temperatures, a find researchers described Tuesday as a big step in the search for "life in the universe."

The planet is just the right size, might have water in liquid form, and in galactic terms is relatively nearby at 120 trillion miles away. But the star it closely orbits, known as a "red dwarf," is much smaller, dimmer and cooler than our sun.

There's still a lot that is unknown about the new planet, which could be deemed inhospitable to life once more is known about it. And it's worth noting that scientists' requirements for habitability count Mars in that category: a size relatively similar to Earth's with temperatures that would permit liquid water. However, this is the first outside our solar system that meets those standards.

Tags: astronomy, space, life, planets, solar systems, science