Thursday, 3 July 2008

Super Science Thursday.- Another Hubble Snap Shot

Via Science Daily.

Another corking picture taken by the Hubble Space Telescope. I don’t think it could ever be possible to anything less than amazed by these.

This time it is a very thin section of a supernova remnant caused by a stellar explosion that occurred more than 1,000 years ago.

In May 1006 observers from Africa to Europe to the Far East witnessed and recorded the arrival of light from what is now called SN 1006, a tremendous supernova explosion caused by the final death throes of a white dwarf star nearly 7,000 light-years away. The supernova was probably the brightest star ever seen by humans, and surpassed Venus as the brightest object in the night time sky, only to be surpassed by the moon. It was visible even during the day for weeks, and remained visible to the naked eye for at least two and a half years before fading away.

In the 1960s radio astronomers detected a near circular ring of material at the recorded position of the supernova. The size of the remnant implied that the blast wave from the supernova had expanded at nearly 20 million miles per hour over the near 1,000 years since the explosion. And then in 1976 came the first detection of the faint optical emission of the supernova, a tiny portion of which is now revealed in detail by the Hubble observation.

Hydrogen gas heated by this fast shock wave emits radiation in visible light.

It is now known that SN 1006 has a diameter of nearly 60 light-years, and it is still expanding at roughly 6 million miles per hour. Even at this speed it takes observations over years to see a significant outward motion of the shock wave against the background stars

SN 1006 resides within our Milky Way Galaxy. In the Hubble image, many background galaxies (the orange objects) far off in the distant universe can be seen dotting the image. Most of the white dots are foreground or background stars in our Milky Way galaxy.


CherryPie said...

Wow! great photo.

Nunyaa said...

Awesome photo !

jmb said...

I never cease to be humbled by seeing these photos they capture out in space. We are such specks of insignificance in our little part of the world.

Womble On Tour said...

Fatastic photo.
This is me being thick but...if the event was witnessed 1,000 years ago, and if it happened 7,000 light years away, doesn't that mean that it happened 8,000 years ago ? (what i mean is, if we see an explosion now that is taking place 7,000 light years away, doesn't that mean that it actually happened 7,000 years ago, and the light by which we see it has only just reached us ?).
If I'm talking tosh, please someone just say "Womble, you're talking tosh".

Anonymous said...

Womble you are not being thick or talking tosh. They don't do a very good job of teaching this stuff in any school system in any country that I know of and I am a retired school teacher who taught special needs students science and math. I hope my answer will fit here. I sent this picture to a friend and she asked some of the same type questions you asked so I am going to put her questions here and my answer if it will all fit. What it means as pertains to your question is that it took 7,000 light years to reach us in the year 1006 AD just like it will have taken 7000 light years for our sunlight to reach that region of space. I think you are mixing apples and oranges.

My friends questions as stated:
My computer (she means her brain) CAN'T compute the idea/fact that the explosion that happened 7,000 years before the light reached earth in 1006, how it can still be putting a cosmic light show across the electromagnetic spectrum. Does this mean the SN 1006 super nova remnant are the remains of an exploded white dwarf star and still "floating" around in space and shock waves in the remnants accelerate particles to extreme energies and a putting on this beautiful show?!?!?! Wow!!! My next question: How did astronomers come to think/believe this?

My answer:

You sure do ask hard questions. I will give the first one a go. Light travels forever. Some of the stars we see in the night sky are millions and even billions of years old and as far away as that, but it takes that long for the light to reach us. Some of them have even burnt themselves out because scientists have been watching specific places for a long enough time that they actually capture the winking out because they are no longer putting out light. Might make more sense this way. It takes around 7 minutes for light from our sun to reach us. If the sun just stopped working (Maybe God gets really mad at us and pulls the plug) it will take 7 minutes before we know what has happened as the remaining light will have passed us and we will be in the darkness of space. Now it won’t happen that way (I don’t think God does things like that) because when our sun goes nova it will expand out as far as Earth and maybe even Mars (not really sure about Mars) and basically in an instant burn the earth to a crispy fired ball that will probably blow itself to smithereens. So like they know now (as well as is possible) where the big bang that started all this is. They can see the fire from it but can’t see the actual place in space because the fire is in the way. Another way to maybe help you is if we could live long enough, what that picture showed us would go past us and we would no longer be able to see it. Remember that light never stops traveling. Meaning we would have to live more than the predicted 7000 light years or so before it all went past us. Also know that a star that has exploded is a rather big thing and is going to spew out a lot of stuff. Our sun will react differently because it is not big enough to go supernova. It will only go nova and then be a white dwarf of very hot iron until it cools off and then it will be a brown dwarf of cold iron. This all takes a very long time so not to worry. Scientists have found both in space already using the Hubble and Chandra telescopes. Hubble takes pictures and Chandra takes X-ray pictures. Now consider that the light spectrum runs from 1 to 100. What we can see with out the aid of Hubble, Chandra, and earth bound telescopes aided by computers ranges around 48 to 52 give or take so we actually can see very little. That is why night vision goggles work, they let us see light in spectrums that our eyes can’t see. So to answer your first question with out all the drivel it is yes.

Now how do scientists, which astronomers are, know this as best they can? Because of Hubble, Chandra, earth bound telescopes, the Mir Russian space station Sky Lab the US space station, the shuttles, and once it is online, if not now, the international space station, not to mention all the probes we have sent into outer space. They, with the use of computers all use the light spectrum to determine this stuff. If you ever watch any of the CSI TV’s shows they are always using the light spectrum and chemicals to find blood on things that the blood for all intent purposes has been washed off. So they pretty much know what each known element looks like using different forms of light spectrum analysis instruments. Like Neptune is blue because it is mostly “largely the result of absorption of red light by methane in the atmosphere” This we know because on Earth red light interacts with methane to produce a blue color. These kind of experiments are what were done on Mir, Sky Lab, the shuttles, and eventually on the International Space Station. Now this is predicated on the belief, and some knowledge obtained from our visits to the moon, that all the universe acts the same way because it started out from the same place and it is all made up of the elements we know about and probably some we don’t know about. Some of this has proven to be true because of the devices we were able to land on Venus that did light spectrum analyses of it’s atmosphere. They gave the same results as on Earth and those things in space that we use to study our universe.

aa said...