~ Why does X-ray astronomy require satellite telescopes?
   

Our atmosphere blocks out radiation that can potentially be harmful to humans. Therefore it blocks out or absorbs X-ray light. That is why scientists use space based satellites to record and observe data from X-ray sources.

~ What other wavelengths require space based telescopes?
   

Not only X-rays require space based telescopes. In order to observe Gamma-ray sources, Infared sources, and Ultraviolet sources the best way to get complete and efficent results is to observe these wavelengths in space. That way the atmosphere is not clouding or fuzzing your view.

Picture   From the book "Explorations", by Thomas Arny, © McGraw-Hill

~ What are some of the other satellite telescopes and what wavelength or energy do they observe??

RXTE:Rossi X-ray Timing Explorer
Launched on December 30th 1995 this satellite studies time variability of X-rays emissions. It measures the energy (in KeVs) of x-rays on very short time scales of fractions of seconds. It detected post X-ray glows from Gamma-ray bursts and soft X-rays from Cyngus X-1.







Beppo Sax: (no longer operational)

Put into orbit around the earth on April 30, 1996, the Beppo Sax satellite is a major part of the Italian Space Program. It primarily observes X-ray sources and has a moderate imaging capabilities.


Alexis: Array of Low Energy X-ray Imaging Sensors

Put into orbit in April of 1993 Alexis measures and surveys the diffuse soft X-ray of the sky and looks at known EUV ( Extreme Ultraviolet ) sources.

Put into orbit in December of 1999.

~ What is Chandra and who is it named after?

Chandra is an X-ray satellite that was launched on July 23, 1999. It finds X-ray sources that can be hundreds of light years away and puts those findings into pictures. Chandra will help astrophyscists solve the mysteries of how the universe was formed, and what is in store for the future. Chandra was named after the Indian-American Nobel laureate: Subrahmanyan Chandrasekhar

~ What type of objects does it observe??

Using the X-ray telescope Chandra observes (in order of size) Galactic Clusters, galaxies, Quasars, Supernovae, Pulsars, nebula, X-ray binaries, and black holes.

~ What can X-rays tell us about celestial objects that visual light cannot?

X-rays (because of their short wavelengths) , as opposed to visual light, can penetrate through otherwise opaque objects e.g. bones X-rays can observe celestial objects that emit shorter wavelengths such as galaxies, quasars, and black holes. Since their wavelengths are shorter than visible light astronomers might not have been able to see them in space.

X-ray image	Optical Image
X-ray	Optical light

~ What is multiwavelength astronomy? Why is it useful?

Many objects in space emit light at various wavelengths or energies. Therefore different telescopes have been constructed to observe different kinds of light. Each wavelength gives astronomers and astrophysicists a differnt view of celestial objects. Multiwavelength astronomy is the observation of different kinds of light or radiation emitted from various astronomical sources. It is useful because it gives astronomers different views of objects at different lights and makes it easier to detect objects that are giving off heat or matter or gas. It is another way of looking at something.








Another view of the electromagnetic spectrum with wavelength and energy values

The constellation Orion at different wavelengths
Radio Image	Infared image	Optical light(visible image)	Ultraviolet image	X-ray image

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