Imagini inedite surprinse de SPITZER si HUBBLE

[Dreamy]

Ultima poza facuta de Spitzer si Hubble seamana mai mult cu o pictura abstracta decat cu o fotografie. Pictura arata nebuloasa Orion intr-o explozie de culori luminoase de infrarosii si ultraviolete. A fost "pictata" de sute de stele pe o panza de gaz si praf, cu o lumina ultravioleta intensa si vanturi stelare puternice pe post de pensule.

In inima picturii se afla un set de patru stele de o masivitate monstruoasa, numite colectiv Trapez. Acesti behemoti sunt de 100 de mii de ori mai luminosi decat Soarele. Comunitatea lor poate fi identificata ca fiind pata galbena de langa centrul compozitiei.

Nuantele de verde au fost dezvaluite de senzorii pentru ultraviolete si lumina ai lui Hubble. Acestea sunt gaze de hidrogen si sulf incalzite de radiatia intensa ultravioleta provenind de la stelele Trapezului.

Nuantele de rosu si portocaliu detectate de Spitzer indica lumina infrarosie de la norii iluminati continand molecule bogate in carbon. Pe Pamant, aceste molecule se gasesc pe painea arsa si in tevile de esapament ale automobilelor.

Stelele aditionale din Orion sunt presarate prin imagine intr-un curcubeu de culori. Spitzer a fotografiat stele foarte tinere adanc infipte intr-un cocon de praf si gaz (punctele portocalii-galbui). Hubble a gasit mai putine stele (pete verzi) si stele in fundal (albastru). Vanturile stelare din aglomeratiile de stele nou nascute imprastiate pe tot cuprinsul norului au definit toate marginile si cavitatile.

Localizata la o distanta de aproape 1500 de ani lumina de Pamant, nebuloasa Orion este cel mai luminos punct din sabia constelatiei vanatorului. Acest nor cosmic este si cea mai apropiata fabrica de stele, iar astronomii cred ca acesta ar contine aproximativ 1000 de stele noi.

Sursa: NASA/Jet Propulsion Laboratory

[pri3st3ss]

This Hubble Space Telescope image shows a collection of galaxies in a cluster called Abell S0740, located more than 450 million light years away. The giant elliptical galaxy ESO 325-G004 can be seen at the cluster's centre.

[pri3st3ss]

Comet clash kicks up dusty haze


Collisions between comets may be kicking up copious amounts of dust observed around a dead star.
This has surprised astronomers, because when the star died and expelled its outer layers, the dust in this system should have been blown away.
A favoured explanation is that the dust is being freshly churned up by comets smashing into each other in the outer fringes of the white dwarf's system.
The dead white dwarf star lies at the centre of the Helix nebula.
Eventually, our own Sun will turn into a white dwarf.

Stars of medium or low mass become white dwarfs after they have exhausted the hydrogen which powers their thermonuclear reactions.
Near the end of the nuclear burning stage, such a star expels most of its outer material, creating a planetary nebula. Only the hot core of the star remains.

Star in the eye

The Helix nebula is a shimmering cloud of gas with an eerie resemblance to a giant eye.
The dusty dead star appears as a dot in the middle of the nebula, like a red pupil in a green monster's eye.
It is located about 700 light-years away in the constellation Aquarius.
Radiation from the dead star's hot core heats the expelled material, causing it to fluoresce with vivid colours.
The Spitzer Space Telescope, an infrared space-based observatory, was able to pick up the glow of a dusty disk circling around the stellar corpse at a distance of about 35 to 150 astronomical units.
An astronomical unit is the distance between our sun and Earth, equivalent to 150 million km or 93 million miles.

"We were surprised to see so much dust around this star," said Dr Kate Su of the University of Arizona, Tucson, the lead author of a paper on the results which is due to appear in Astrophysical Journal Letters.

"The dust must be coming from comets that survived the death of their sun."

Cosmic smash-up

A few million years ago, when the star was still lively like our sun, its comets - and possibly planets - would have been in stable orbits, travelling harmoniously around the star.
But when the star died, any inner planets would have been burned up or engulfed as the star expanded.
Outer planets, asteroids and comets would have been thrown into each other's paths.

Our own Solar System is expected to undergo a similar transformation in about five billion years.

Like the Helix nebula, it will sparkle with colours. Our sun, which will have become a white dwarf, will be circled by a band of surviving outer planets and colliding comets.

The Spitzer data might also help explain a mystery surrounding the Helix nebula's white dwarf.
Previous observations indicated that the white dwarf was throwing out highly energetic X-rays. While the white dwarf is hot - about 110,000 Kelvin (109,727C; 200,000F), it is not hot enough to explain the energetic X-rays.
Astronomers thought that the white dwarf was accreting matter onto itself from a hidden companion star.
But the Spitzer observations point to a different answer. According to team member Dr You-Hua Chu of the University of Illinois at Urbana-Champaign, material in the dusty disk surrounding the white dwarf might be falling on to the star and triggering the X-ray outbursts.

fig 1: the helix nebula was photographed by the Spitzer Space Telescope Nasa/JPL-Caltech/K. Su (University of Arizona)

pt o dimensiune mai mare a pozei, dati un mp

[pri3st3ss]

si despre jupiter...

Nasa's Galileo spacecraft recorded this spectacular image of Jupiter's volcanic moon Io. The blue plume, seen at the top of the image, is a sulphurous eruption from a caldera known as Pillan Patera.

[pri3st3ss]

sa va mai arat ceva..superb...


It's exactly 20 years since astronomers spotted one of the brightest exploding stars in more than 400 years. Supernova 1987A has since become one of the most studied objects in the sky. Hubble's picture shows rings of gas being energised by the shockwave from the explosion.

[pri3st3ss]

Water detected on distant planet


Water has been detected for the first time in the atmosphere of a planet outside our Solar System.
The planet, known as HD 209458b, is a Jupiter-like gas giant located 150 light-years from Earth in the constellation Pegasus.
Other scientists reported in February they were unable to find evidence of water in this planet's atmosphere, as well as in another Jupiter-like planet.
Details of the research are published in the Astrophysical Journal.



"Understanding the distribution of water in other solar systems is important for understanding whether or not conditions for life are possible' -Travis Barman
Water vapour (or steam) was expected to be present in atmospheres of most known extrasolar planets, even those that orbit more closely to their parent star than Mercury is to our Sun.
For the majority of exoplanets, their close proximity to their parent star has made detecting water and other compounds difficult.

The identification reported here takes advantage of the fact that HD209458b, as seen from Earth, passes directly in front of its star every three and half days.

As a planet passes in front of a star, its atmosphere blocks a different amount of starlight at different wavelengths of light.
In particular, absorption by water in the atmosphere of a giant planet makes the planet appear larger across a specific part of the infrared spectrum compared to wavelengths in the visible spectrum.


Cosmic puzzle

Astronomer Travis Barman, from the Lowell Observatory in Flagstaff, US, found what he says is strong evidence for water absorption in the atmosphere of the transiting planet.
The conclusions stemmed from an analysis of Hubble Space Telescope measurements by Harvard University astronomer Heather Knutson and new theoretical models developed by Dr Barman.
He said his findings provide good reason to believe other planets beyond our Solar System also have water vapour in their atmospheres, despite the failure by another group to find water on the same world.
"I'm very confident," said Dr Barman, "it's definitely good news because water has been predicted to be present in the atmosphere of this planet and many of the other ones for some time."

He added that a Jupiter-like gaseous planet such as this one, as opposed to a rocky one like Earth, is highly unlikely to harbour any kind of life.
"Certainly this is part of that puzzle - understanding the distribution of water in other solar systems is important for understanding whether or not conditions for life are possible," he explained.



Planet shine

Telescope technologies are being developed that will probe the very faint light from these objects for tell-tale signs of biology.
These are the same "life markers" known to be present in light reflected off the Earth - so-called "earthshine".
They include signatures for water, and gases such as oxygen and methane and perhaps more complex molecules such as chlorophyll - the pigment which makes the process of photosynthesis possible.

HD209458b belongs to a type of extrasolar planet known as "hot Jupiters". These planets orbit precariously close to their stars.

The planet's outer atmosphere is expanded and heated so much by the nearby star that it is escaping the planet's gravity. Hydrogen boils off in the upper atmosphere under the searing heat from the star.

[pri3st3ss]

FIG 1 :  In this composite image of spiral galaxy M106 (NGC 4258), optical data from the Digitized Sky Survey is shown as yellow, radio data from the Very Large Array appears as purple, X-ray data from Chandra is coded blue, and infrared data from the Spitzer Space Telescope appears red. Two anomalous arms, which aren't visible at optical wavelengths, appear as purple and blue emission.

FIG 2: The Seven Sisters, also known as the Pleiades star cluster, seem to float on a bed of feathers in a new infrared image from NASA's Spitzer Space Telescope. Clouds of dust sweep around the stars, swaddling them in a cushiony veil.
The Pleiades, located more than 400 light-years away in the Taurus constellation, are the subject of many legends and writings. Greek mythology holds that the flock of stars was transformed into celestial doves by Zeus to save them from a pursuant Orion. The 19th-century poet Alfred Lord Tennyson described them as "glittering like a swarm of fireflies tangled in a silver braid."The star cluster was born when dinosaurs still roamed the Earth, about 100 million years ago.
This image is made up of data taken by Spitzer's multiband imaging photometer and its infrared array camera. Light with a wavelength of 4.5 microns is blue; light of 8 microns is green; and light of 24 microns is red.

FIG 3:This image shows infrared light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns is red and orange; light of 4.5 microns is green; and light of 3.6 microns is blue.

[pri3st3ss]

o poza marita a nebuloasei ...

[darkness]

greu,nene,greu..


This Hubble telescope image of a dense swarm of stars shows the central region of the globular cluster NGC 2808.

Astronomers were surprised when Hubble spied three generations of cluster stars. The discovery is far different from the standard picture of a globular cluster. For decades, astronomers thought that cluster stars formed at the same time, in the same place, and from the same material, and have co-evolved for billions of years.

Globular clusters are the homesteaders of our Milky Way Galaxy, born during our galaxy's formation. They are compact swarms of typically hundreds of thousands of stars held together by gravity.

All the stars in NGC 2808 were born within 200 million years very early in the life of the 12.5-billion-year-old massive cluster. Of the about 150 known globular clusters in our Milky Way Galaxy, NGC 2808 is one of the most massive, containing more than 1 million stars.

The sharp resolution of Hubble's Advanced Camera for Surveys measured the brightness and colors of the cluster stars to find the three stellar populations.

The Hubble images were taken in May 2005 and in August and November 2006.

The science team includes G. Piotto, A.P. Milone, and S. Villanova (University of Padua [Padova]), L.R. Bedin (European Space Agency, European Organization for Astronomical Research in the Southern Hemisphere, and Space Telescope Science Institute), J. Anderson (Rice University), I.R. King (University of Washington), S. Cassisi and A. Pietrinferni (INAF- Astronomical Observatory of Collurania, Teramo), and A. Renzini (INAF-Astronomical Observatory of Padua [Padova]).

Object Name: NGC 2808



si pt imaginea 2
he supernova remnant (SNR), known as "E0102" for short, is the greenish-blue shell of debris just below the center of the Hubble image. Its name is derived from its cataloged placement (or coordinates) in the celestial sphere. More formally known as 1E0102.2-7219, it is located almost 50 light-years away from the edge of the massive star-forming region, N 76, also known as Henize 1956 in the Small Magellanic Cloud. This delicate structure, glowing a multitude of lavenders and peach hues, resides in the upper right of the image.

Determined to be only about 2,000 years old, E0102 is relatively young on astronomical scales and is just beginning its interactions with the nearby interstellar medium. Young supernova remnants like E0102 allow astronomers to examine material from the cores of massive stars directly. This in turn gives insight on how stars form, their composition, and the chemical enrichment of the surrounding area. As well, young remnants are a great learning tool to better understand the physics of supernova explosions.

E0102 was observed in 2003 with the Hubble Advanced Camera for Surveys. Four filters that isolate light from blue, visible, and infrared wavelengths and hydrogen emission were combined with oxygen emission images of the SNR taken with the Wide Field Planetary Camera 2 in 1995.

The Small Magellanic Cloud is a nearby dwarf galaxy to our own Milky Way. It is visible in the Southern Hemisphere, in the direction of the constellation Tucana, and lies roughly 210,000 light-years distant.

[pri3st3ss]

 A Colorful Demise - im 1

This image shows the "last hurrah" of a star like our sun. The star is ending its life by casting off its outer layers of gas, which formed a cocoon around the star's remaining core. Ultraviolet light from the dying star makes the material glow.
The burned-out star, called a white dwarf, is the white dot in the center. Our sun will eventually burn out and shroud itself with stellar debris, but not for another 5 billion years.


Eagle Nebula   - im 2
A star-making region famous for its space pillars appears in this infrared view from Spitzer. Green denotes cooler dust, including the pillars seen in the center. Red represents hotter dust thought to have been warmed by the explosion of a massive star about 8,000 to 9,000 years ago.
Astronomers estimate that the explosion's blast wave would have spread outward and toppled the three pillars about 6,000 years ago. Since light from the Eagle nebula takes 7,000 years to reach us, this means we wouldn't witness the destruction for about 1,000 years.



Alien World   - im 3
This is the first-ever map of the surface of a planet beyond our solar system. The map, which shows temperature variations across the cloudy tops of a gas giant called HD 189733b, is made up of infrared data taken by Spitzer. Hotter temperatures are represented in brighter colors.
The map tells astronomers that temperatures on HD 189733b are fairly even all around. While the dark side is about 650 degrees Celsius (about 1,200 degrees Fahrenheit), the sunlit side is just a bit hotter at 930 degrees Celsius (1,700 degrees Fahrenheit).

[pri3st3ss]

Nearly 12.5 million light-years away, in the dwarf galaxy NGC 4449, stellar fireworks on display have been captured by the Hubble Space Telescope's Advances Camera for Surveys.
It is likely that the current widespread starburst in the galaxy was triggered by interaction or merger with a smaller companion.

Observed in the visible (blue and green), infrared, and hydrogen-alpha regions of the spectrum, hundreds of thousands of vibrant blue and red stars are visible in this new image. Hot bluish white clusters of massive stars are scattered throughout the galaxy, interspersed with numerous dustier reddish regions where star formation is taking place. Massive, dark clouds of gas and dust are silhouetted against starlight.



pt o poza mai mare  : http://www.esa.int/images/heic0711a.jpg

[pri3st3ss]

Exploding star in nearby galaxy



The latest image from the NASA/ESA Hubble Space Telescope reveals a sharp view of the spiral galaxy NGC 2397. It shows a rare Hubble view of the early stages of supernova SN 2006bc, discovered in March 2006.
NGC 2397 is a classic spiral galaxy with long, prominent dust lanes along the edges of its arms, seen as dark patches and streaks silhouetted against the starlight. Hubble's exquisite resolution allows the study of individual stars in nearby galaxies.
Located nearly 60 million light-years away from Earth, NGC 2397 is typical of most spirals, with mostly older, yellow and red stars in its central portion, while star formation continues in the outer, bluer spiral arms. The brightest of these young, blue stars can be seen individually in this high-resolution view from Hubble's Advanced Camera for Surveys (ACS).
One atypical feature of this Hubble image is the view of supernova SN 2006bc taken when its brightness was on the decrease. Astronomers at Queen's University Belfast in Northern Ireland, led by Professor of Astronomy Stephen J. Smartt, requested the image as part of a long project studying massive exploding stars — supernovae. Exactly which types of stars will explode and the lowest mass of star that can produce a supernova are not known. 
When a supernova is discovered in a nearby galaxy, the group begins a painstaking search of earlier Hubble images of the same galaxy to locate the star that exploded later; often one of hundreds of millions of stars in the galaxy. This is a little like sifting through days of CCTV footage to find one frame showing a suspect.
If the astronomers find a star at the location of the later explosion, they may work out the mass and type of star from its brightness and colour. Only six such stars have been identified before they exploded and Smartt's team have discovered the nature of five of them.
In their latest work on Hubble images, to be presented at the UK National Astronomy Meeting 2008 in Belfast, the team reveals the results of their ten-year search for these elusive supernova precursor stars. It seems that stars with masses as low as seven times the mass of the Sun can explode as supernovae. The team have not found any very massive stars that exploded, suggesting that the most massive stars may collapse to form black holes either without producing a supernova or by producing one that is too faint to observe. This intriguing possibility will be discussed at the meeting.
A public lecture at Queen's University Belfast showing how the Hubble Space Telescope has built a bridge between science and art will coincide with a presentation of the latest scientific study of Hubble galaxy images by astronomers at the university. The images were obtained on 14 October 2006 with Hubble's Advanced Camera for Surveys (ACS) with three different colour filters (blue, green and near-infrared).
NGC 2397, pictured in this Hubble image, is a classic spiral galaxy with long prominent dust lanes along the edges of its arms, seen as dark patches and streaks silhouetted against the starlight. Hubble's exquisite resolution allows the study of individual stars in nearby galaxies.
Located nearly 60 million light-years from Earth, NGC 2397 is typical of most spiral galaxies, with mostly older, yellow and red stars in its central portion, while star formation continues in the outer, bluer spiral arms. The brightest of these young, blue stars can be seen individually in this high-resolution view from Hubble's Advanced Camera for Surveys.
One atypical feature of this Hubble image of the galaxy NGC 2397 is the view of supernova SN 2006bc (marked in the white rectangle) taken when it was still fairly faint and its brightness on the increase. Astronomers from Queen's University Belfast in Northern Ireland, led by Professor of Astronomy Stephen J. Smartt, requested the image as part of a long project studying massive exploding stars — supernovae. Exactly which types of star will explode and the lowest mass of star that can produce a supernova are not known.

Credits: NASA/ ESA/

[pri3st3ss]

Black hole found in Omega Centauri



Omega Centauri has been known to be an unusual globular cluster for a long time. A new result obtained by Hubble and the Gemini Observatory reveals that the globular cluster may have a rare intermediate-mass black hole hidden in its centre, implying that it is likely not a globular cluster at all, but a dwarf galaxy stripped of its outer stars.
Omega Centauri, the largest and brightest globular cluster in the sky, is visible from Earth with the naked eye and is one of the favourite celestial objects for stargazers from the southern hemisphere. Although 17 000 light-years away, it located just above the plane of the Milky Way and appears almost as large as the full Moon when seen from a dark, rural area.
Images obtained with the Hubble Space Telescope's Advanced Camera for Surveys and data from the GMOS spectrograph on the Gemini South telescope in Chile show that Omega Centauri appears to harbour an elusive and rare intermediate-mass black hole in its centre.
"This result shows that there is a continuous range of masses for black holes - from supermassive, to intermediate-mass, to small stellar mass types", explained astronomer Eva Noyola of the Max-Planck Institute for Extraterrestrial Physics in Garching, Germany, leader of the team that made the discovery. 
Noyola and colleagues measured the motions and brightness of the stars at the centre of Omega Centauri. The measured velocities of the stars in the centre are related to the total mass of the cluster and were far higher than expected from the mass deduced from the number and type of stars seen. So, there had to be something extraordinarily massive (and invisible) at the centre of the cluster responsible for the fast-swirling dance of stars — almost certainly a black hole of about 40 000 solar masses.
"Before this observation, we had only one example of an intermediate-mass black hole — in the globular cluster G1, in the nearby Andromeda Galaxy", said Karl Gebhardt at the University of Texas, Austin, USA, member of the team that made the discovery. According to Noyola the presence of an intermediate-mass black hole is the most likely reason for the stellar speedway near the cluster's centre. These intermediate-mass black holes could even be the seeds to create supermassive black holes. This provides astronomers with important new clues to understand one of the possible formation mechanisms of these galactic monsters.
This discovery also has important implications on the very nature of Omega Centauri. Globular clusters contain up to one million old stars bound tightly by gravity and are found in the outskirts of many galaxies including our own. Omega Centauri already has several characteristics that distinguish it from other globular clusters: it rotates faster than average, its shape is highly flattened and it consists of several generations of stars, while typical globular clusters usually consist of just one generation of old stars. It is also about 10 times as massive as other big globular clusters, almost as massive as a small galaxy.
The fact that intermediate-mass black holes may be rare and exist only in former dwarf galaxies that have been stripped of their outer stars, reinforces the idea that Omega Centauri is not a globular cluster but indeed a dwarf galaxy stripped of its outer stars in an earlier encounter with the Milky way.


 

[Rayden]

@ pri3st3ss

merci ptr poze..super tari!

[spooky]

fig 1: the helix nebula was photographed by the Spitzer Space Telescope Nasa/JPL-Caltech/K. Su (University of Arizona)

poza asta de mai sus ... parca seamana cu conturul Romaniei :D