"Good Seeing"
May 27th 2011 00:54
Category: Cosmic Objects
Image of Centaurus A' using a combination of X-ray data (blue) mixed with radio telescope data (orange) and visible-light the image reveals a much more detailed picture of the object.
Editorial note: Some may be wondering what became of CarlCan well Carl thought he needed a name change he is now called C more stars same bloke different name.
Good seeing is a term used in astronomy to gauge what the atmospheric conditions may be.
Summer nights has it’s challenges apart from the thunderstorms the upper atmosphere can be very turbulent making visual observation at night difficult. Atmospheric conditions do change nightly irrespective of the season, that’s why stars seem to ‘twinkle’.
Astronomy is noted for the most part as being an optical pursuit although most images we see in publications are digital representations. ` In the good old days’ (listen to me, I sound like one of those old timers saying “during the War!”) images were taken on film or photographic plates.
In the last 30 years with the advent of Charged Coupled Device (CCD ) most images used in astronomy are captured by CCD cameras, the techniques used to obtain these images has remained the same all-be –it with some substantial improvements. There is no need to process film negatives the convenience of the digital chip has enabled us to see the images produced almost instantaneously.
Digital images can be processed electronically. Some images contain a mix of X-ray and radio emissions data that show the dramatic changes that we would not ordinarily see using conventional imaging techniques.
Apart from the optical wavelengths there are many tools used to study the night sky.
Radio Astronomy plays an active role in astronomy research. The radio telescope can ‘see’ radio images, images that cannot be seen optically because the wavelengths are much shorter than visible light.
Some deep sky objects appear bright when seen with naked eye or through a telescope, but in most cases we are not ‘seeing ‘ the full picture.
By combining X-ray images taken by specialized satellites incorporating data from the radio telescopes including optical images we much deeper into the core of the object.
Using these techniques allows us to see the ‘hidden’ features the subtle wisps of dust clouds. By combining images sourced from different wavelengths we can build a much more detailed image of the object as a whole.
Centaurus A a galaxy some 12 million light-years away from Earth appears bright when seen in visible light. We can see optically the dark dust patches within the galaxy.
When seen through radio wavelengths the objects surrounding the galaxy are much brighter. By using the radio telescope we can see the ‘hidden’ workings of a galaxy. The radio image shows a pair of opposed jets produced by a super massive black hole.
Credit: Visible: ESO / WFI; radio: MPI / ESO / A. Weiss & others; X-ray: NASA / CXC / R. Kraft Etal.
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Comment by S.L.
The Political Brief
Comment by CMoreStars
Astroearth
Camera Sense
Hi S.L.
Thank you for the comment.
Though it was time for a name change.
Comment by S.L.
The Political Brief
Nah, I think I'll just keep my own, it's easier to remember. LOL