not even a tiny fraction of God's material glory

[dasa]

 

[This message has been edited by dasa (edited 04-18-2002).]

[dasa]

From JNDAS: Image no longer exists, so deleted.

[Gauracandra]

I came across this picture in an article and it reminded me of this thread.

 

 

[theist]

I have always wondered about these colors.Real or NASA touchup I wonder?

[bhaktajoy]

[bhaktajoy]

 

 

 

 

 

NASA's Hubble Space Telescope has snapped a view of a stellar demolition zone in our Milky Way Galaxy: a massive star, nearing the end of its life, tearing apart the shell of surrounding material it blew off 250,000 years ago with its strong stellar wind. The shell of material, dubbed the Crescent Nebula (NGC 6888), surrounds the "hefty," aging star WR 136, an extremely rare and short-lived class of super-hot star called a Wolf-Rayet. Hubble's multicolored picture reveals with unprecedented clarity that the shell of matter is a network of filaments and dense knots, all enshrouded in a thin "skin" of gas [seen in blue]. The whole structure looks like oatmeal trapped inside a balloon. The skin is glowing because it is being blasted by ultraviolet light from WR 136.

 

Hubble's view covers a small region at the northeast tip of the structure, which is roughly three light-years across. A picture taken by a ground-based telescope [lower right] shows almost the entire nebula. The whole structure is about 16 light-years wide and 25 light-years long. The bright dot near the center of NGC 6888 is WR 136. The white outline in the upper left-hand corner represents Hubble's view.

 

Hubble's sharp vision is allowing scientists to probe the intricate details of this complex system, which is crucial to understanding the life cycle of stars and their impact on the evolution of our galaxy. The results of this study appear in the June issue of the Astronomical Journal.

 

WR 136 created this web of luminous material during the late stages of its life. As a bloated, red super-giant, WR 136 gently puffed away some of its bulk, which settled around it. When the star passed from a super-giant to a Wolf-Rayet, it developed a fierce stellar wind - a stream of charged particles released from its surface - and began expelling mass at a furious rate. The star began ejecting material at a speed of 3.8 million mph (6.1 million kilometers per hour), losing matter equal to that of our Sun's every 10,000 years. Then the stellar wind collided with the material around the star and swept it up into a thin shell. That shell broke apart into the network of bright clumps seen in the image. The present-day strong wind of the Wolf-Rayet star has only now caught up with the outer edge of the shell, and is stripping away matter as it flows past [the tongue-shaped material in the upper right of the Hubble image].

 

The stellar wind continues moving outside the shell, slamming into more material and creating a shock wave. This powerful force produces an extremely hot, glowing skin [seen in blue], which envelops the bright nebula. A shock wave is analogous to the sonic boom produced by a jet plane that exceeds the speed of sound; in a cosmic setting, this boom is seen rather than heard. The outer material is too thin to see in the image until the shock wave hits it. The cosmic collision and subsequent shock wave implies that a large amount of matter resides outside the visible shell. The discovery of this material may explain the discrepancy between the mass of the entire shell (four solar masses) and the amount of matter the star lost when it was a red super-giant (15 solar masses).

 

The nebula's short-term fate is less spectacular. As the stellar wind muscles past the clumps of material, the pressure around them drops. A decrease in pressure means that the clumps expand, leading to a steady decline in brightness and fading perhaps to invisibility. Later, the shell may be compressed and begin glowing again, this time as the powerful blast wave of the Wolf-Rayet star completely destroys itself in a powerful supernova explosion.

 

The nebula resides in the constellation Cygnus, 4,700 light-years from Earth. If the nebula were visible to the naked eye, it would appear in the sky as an ellipse one-quarter the size of the full moon. The observations were taken in June 1995 with the Wide Field and Planetary Camera 2. Scientists selected the colors in this composite image to correspond with the ionization (the process of stripping electrons from atoms) state of the gases, with blue representing the highest and red the lowest observed ionization.

 

[bhaktajoy]

 

 

 

 

 

Just weeks after NASA astronauts repaired the Hubble Space Telescope in December 1999, the Hubble Heritage Project snapped this picture of NGC 1999, a nebula in the constellation Orion. The Heritage astronomers, in collaboration with scientists in Texas and Ireland, used Hubble's Wide Field Planetary Camera 2 (WFPC2) to obtain the color image.

 

NGC 1999 is an example of a reflection nebula. Like fog around a street lamp, a reflection nebula shines only because the light from an embedded source illuminates its dust; the nebula does not emit any visible light of its own. NGC 1999 lies close to the famous Orion Nebula, about 1,500 light-years from Earth, in a region of our Milky Way galaxy where new stars are being formed actively. The nebula is famous in astronomical history because the first Herbig-Haro object was discovered immediately adjacent to it (it lies just outside the new Hubble image). Herbig-Haro objects are now known to be jets of gas ejected from very young stars.

 

The NGC 1999 nebula is illuminated by a bright, recently formed star, visible in the Hubble photo just to the left of center. This star is cataloged as V380 Orionis, and its white color is due to its high surface temperature of about 10,000 degrees Celsius (nearly twice that of our own Sun). Its mass is estimated to be 3.5 times that of the Sun. The star is so young that it is still surrounded by a cloud of material left over from its formation, here seen as the NGC 1999 reflection nebula.

 

The WFPC2 image of NGC 1999 shows a remarkable jet-black cloud near its center, resembling a letter T tilted on its side, located just to the right and lower right of the bright star. This dark cloud is an example of a "Bok globule," named after the late University of Arizona astronomer Bart Bok. The globule is a cold cloud of gas, molecules, and cosmic dust, which is so dense it blocks all of the light behind it. In the Hubble image, the globule is seen silhouetted against the reflection nebula illuminated by V380 Orionis. Astronomers believe that new stars may be forming inside Bok globules, through the contraction of the dust and molecular gas under their own gravity.

 

NGC 1999 was discovered some two centuries ago by Sir William Herschel and his sister Caroline, and was cataloged later in the 19th century as object 1999 in the New General Catalogue.

 

These data were collected in January 2000 by the Hubble Heritage Team with the collaboration of star-formation experts C. Robert O'Dell (Rice University), Thomas P. Ray (Dublin Institute for Advanced Study), and David Corcoran (University of Limerick).

 

[Avinash]

The colors shows are not real. The colors are changed to bring out the contrast. Such an image is known as false color image. Please do not think that NASA is trying ti cheat anybody by changing colors. It has not been made secret. Rather, if you read journals, you will find that they accept that colors are changed. This is done not only by NASA but in any photograph that is taken by man made satellite or space telescope.

[Jahnava Nitai Das]

How is the color change determined and what is the original color?

 

[Gauracandra]

I don't think the colors are fabricated. Perhaps enhanced to draw contrast. It is actually one of my dreams to one day purchase are really expensive telescope, just splurge and buy a top of the line model. I can't afford that yet, but one day I hope to. My thinking is that the vast majority of human society, past and present has never had the access to view such images. I don't know the answers to life, but just viewing such images seems to make the world o much brighter.

[Avinash]

Just by looking at a false color image, we can not know the original color. For that we need another image known as true color image. True color image is used if we want to know the original colors. False color image is used to bring out the contrast.

 

Let me give an example. Suppose that satellite image is taken of a forest which is, of course, full of trees. It is known that the true color will be almost full of green. But suppose that we are interested in the contrast i.e. we want to know where it is more green and where it is less green. A color can be chosen. For example, I can choose red. Where it is bright green, I will show bright red and so on. It has been found that human eye is more sensitive to the contrast in red colors than in green colors. For creating false color images, satellite records brightness as numbers and then these numbers are colors coded.

[Avinash]

It is not that all images released by NASA are false color images. Some are and some are not. NASA quite clearly mentions which are false color and which are true color.

 

I have a telescope. I get quite fascinated by looking at the stars. Everyday I look at rising Sun. In the night I go to the roof top and watch stars. I have been studying about stars since I was a child. I can recognize many stars. By recognizing I mean, I know their names, categories, distance from Earth. I can also recognize all constellations that have been named. It was my ardent desire to be an astronomer since I was a child. But, somehow I came into software.

[gHari]

The real colours actually differ depending on the position of the viewer. Light loses its frequency over time in deep space (known as the red shift). Some colours out there are not even visible to the human eye.

 

This reminds me of the Search for the Lost Chord by the Moody Blues:

<blockquote>[From The Actor]

 

The curtain rises on the scene

With someone chanting to be free

The play unfolds before my eyes

There stands the actor who is me

 

[The Word]

 

This garden universe vibrates complete.

Some we get a sound so sweet.

Vibrations reach on up to become light,

And then thru gamma, out of sight.

Between the eyes and ears there lie,

The sounds of colour and the light of a sigh.

And to hear the sun, what a thing to believe.

But it's all around if we could but perceive.

To know ultra-violet, infra-red and X-rays,

Beauty to find in so many ways.

Two notes of the chord, that's our fluoroscope.

But to reach the chord is our lifes' hope.

And to name the chord is important to some.

So they give a word, and the word is OM.</blockquote>

Actually I too studied Astronomy and Astrophysics in University in the late sixties. I worked in the observatory measuring the pulsating light from binary star systems. We would use different filters to screen out various wavelength frequencies in order to better 'see' the differences in energy emanations as the stars revolved around one another. Likely these pics have been filtered to remove the Moody Blues from them too or perhaps the Moody Blues have been changed from infrared to blue.

 

Space is surely the ultimate humbler on this side of the great divide. And it is only by a spark of His splendor that Sri Krsna creates it all. If the stars can't shake us loose from the drama of mundane life in this world of cement and pavement, then we must move to the country where there are even more stars to dwarf our egos.

 

gHari

[Avinash]

You are talking about true color image. False color image depends on brightness and not the real color itself.

 

[Avinash]

Likely these pics have been filtered to remove the Moody Blues from them too or perhaps the Moody Blues have been changed from infrared to blue.

 

This reminds me of mapped color image. Since infrared and ultraviolet can't be perceived by human eye, these waves are mapped to the frequencies that can be perceived by human eye. The image thus generated is known as mapped color image.

[Gauracandra]

[Somesh Kumar]

Ananta koti brahmanda nayak Sri Krishna ki Jai!!

[vsdprasad]

Microsoft is R&Dng a virtual observatory wherein you can see the mysteries of the universe.

go to this site Sloan Digital Sky center (http://skyserver.sdss.org/en/) and use the skyserver tools to navigate across the universe !

 

And heres the link for Microsoft's Research on Virtual Observatory. (http://research.microsoft.com/barc/virtual_observatory.asp) Anyone wants to contribute to its research?? !

 

-Prasad.