Clipmarks | invictus's 'astronomy' clips

'Hundreds of worlds' in Milky Way

Mon, 18 Feb 2008 01:52:48 GMT

clipped by: invictus

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

clipped by: invictus

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

Close Encounter with Mars

Mon, 17 Dec 2007 23:56:56 GMT

clipped by: invictus

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

clipped by: invictus
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

clipped by: invictus

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

clipped by: invictus

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

Colossal tail trails dying star

Wed, 15 Aug 2007 22:49:59 GMT

clipped by: invictus
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

clipped by: invictus

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

clipped by: invictus

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

Roman Towns Built With Astronomy

Tue, 08 May 2007 17:59:21 GMT

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Clip Source: dsc.discovery.com

Roman Towns Built With Astronomy

Built Toward Sunrise?

Ancient Romans built their towns using astronomically aligned grids, an Italian study has concluded.

Published recently on the physics Web site, www.arXiv.org, maintained at Cornell University in Ithaca, New York, the research examined the orientation of virtually all Roman towns in Italy.

"It emerged that these towns were not laid out at random. On the contrary, they were planned following strong symbolic aspects, all linked to astronomy," Giulio Magli, of the mathematics department at Milan’s Polytechnic University, told Discovery News.

Part of a wider study published in Magli's book "Secrets of the Ancient Megalithic Towns," the research examined the orientation of some 38 towns in Italy.

Magli explained that ancient Roman writers, including Ovid and Plutarch, documented how the foundation of a new town took into account the flight of birds and astronomical references.

Tags: archaeology, astronomy, ancient history, stellar alignments, rome, science

Potentially habitable planet found

Wed, 25 Apr 2007 14:36:07 GMT

clipped by: invictus

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

Bizarre Hexagon Spotted on Saturn

Wed, 28 Mar 2007 15:59:22 GMT

clipped by: invictus

Clip Source: spaceweather.com

BIZARRE HEXAGON: "We've never seen anything like it on any other planet," says atmospheric scientist Kevin Baines of the Jet Propulsion Laboratory. It is a hexagon twice as wide as Earth encircling Saturn's north pole. First observed by the Voyager spacecraft in the 1980s, the hexagon has been sighted anew by the Cassini probe:

In this infrared photo taken by Cassini's VIMS camera, the blue color traces auroras at high altitudes in Saturn's atmosphere. Red indicates the amount heat filtering up through clouds below. Researchers believe the auroras and the hexagon are unrelated.

The hexagon could be a distant cousin of Earth's polar vortex, but while Earth's vortex is a circle, Saturn's may be molded into a hexagon by some strange pattern of atmospheric waves. "Saturn's thick atmosphere where circularly-shaped waves and convective cells dominate is perhaps the last place you'd expect to see such a six-sided geometric figure," says Baines. In short, it's a mystery.

Tags: astronomy, solar system, planets, saturn

New Green Comet: "Lovejoy"

Tue, 20 Mar 2007 15:32:14 GMT

clipped by: invictus

Clip Source: spaceweather.com

NEW COMET LOVEJOY: On March 15th, Terry Lovejoy of Thornlands, Australia, discovered a new comet (C/2007 E2) in the southern constellation Indus. Remarkably, to make the find he used not a telescope but just an off-the-shelf digital camera--a Canon 350D. At Lovejoy's request, John Drummund of Gisborne, New Zealand, confirmed the comet with this photo taken through a 0.41-m reflector:

The new comet is green and shines like a 9th magnitude star, too dim for the unaided eye but an easy target for large backyard telescopes in the southern hemisphere: ephemeris.

After five days of tracking, Comet Lovejoy's trajectory is known. The orbit is cockeyed, almost perpendicular to the rest of the solar system. At the moment the comet is swooping up from below, moving from southern to northern skies. At closest approach to Earth (0.44 AU) in late April, Comet Lovejoy is expected to brighten to 7th magnitude, still not a naked-eye comet but easy to see through small telescopes.

Tags: astronomy, space, comets, solar system

Small asteroid risk is higher than estimated

Fri, 09 Mar 2007 19:04:35 GMT

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clipper's remarks:

The chairman of this week's Planetary Defense Conference, William Ailor of the Aerospace Corp., a nonprofit established by Congress to support the Air Force's space defense program, said scientists generally agree that the risk to Earth from large asteroids is small. Researchers have identified more than 700 of these potential "planet killers" -- out of an estimated 1,000 -- and found that not one is on a collision course with Earth.

"But with the smaller ones, the asteroids in the [150-yard] range, we're finding more and more," Ailor said yesterday. "They're hard to detect, and it's hard to predict where they are headed, but they can do a great deal of damage." NASA estimates that there are as many as 100,000 of the smaller asteroids in near-Earth orbit and that about 20 are "potentially hazardous."

Clip Source: www.washingtonpost.com

By Marc Kaufman

The risk that an asteroid capable of wiping out humanity will crash into Earth is minuscule, new calculations suggest, but the chances of a smaller one destroying a city or setting off a catastrophic tsunami remain unclear and may be higher than previous estimates.

The calculations were presented at a four-day meeting in Washington this week, leading scores of scientists present to conclude that NASA needs to move aggressively to meet a congressional deadline for identifying most of the potentially hazardous smaller asteroids and to develop ways to deflect them if they home in on Earth.

But in a report released to Congress yesterday, the space agency said it does not have the funds to do the precautionary work, called for in its 2005 authorization bill.

Tags: astronomy, neo, asteroid, impact risk, collision, disaster