Ways of SeeingWays of Seeing

X-Rays

By

Myles Gray

&

Steve Dwyer

Father of the X-RayFather of the X-Ray

• Wilhelm Conrad Roentgen was the first to discover the X-Ray. He first noted on their existence on November 8, 1895. He noticed that while he was working in his laboratory an object on the other side of the room began to glow.

Parts of the SpectrumParts of the Spectrum

• All parts of the electromagnetic spectrum are essentially the same thing: electromagnetic radiation. The only differences between them all are the frequency and wavelengths of the different types of waves. X-Rays are mostly blocked out of the atmosphere because of the frequency of the waves. Because of this, X-Ray observatories, like the Chandra, have to be far into space to collect accurate data. The Chandra is almost one third of the way to the moon!

X-Rays in the SpectrumX-Rays in the Spectrum

• X-Rays are just one portion of the electromagnetic spectrum. Their wavelengths are larger than those of gamma rays, but smaller then the wavelengths of all other portions of the electromagnetic spectrum.

A New FrontierA New Frontier

• Perhaps the most important aspect of the X-Ray is its use in the field of medicine. The first X-Ray photo of the human body was taken of the hand of a corpse by Wilhelm Roentgen himself in his laboratory in Vienna.

A Second FrontierA Second Frontier

• The X-Ray has also become a very useful tool in the field of astronomy. The first X-Ray telescope was made by American Science and Engineering in Cambridge, MA in 1965.

Chandra X-Ray ObservatoryChandra X-Ray Observatory

• The most important X-Ray astronomy mission of the current decade is NASA’s Chandra X-Ray Observatory, which was launched on July 23, 1999. It contains four sets off nested mirrors, and is the premier X-Ray observatory that has ever been launched.

Chandra X-Ray ObservatoryChandra X-Ray Observatory

• The Chandra X-Ray Observatory has opened an important door for the field of astronomy. The mirrors on the Chandra have been polished to a smoothness of a few atoms. The mirrors are so strong that they can see twice as far and with five times greater detail than any other X-Ray telescope.

Jovian X-ray and Ultraviolet Emissions

Jovian X-ray and Ultraviolet Emissions

Here is a composite image of Jupiter taken by the Chandra Observatory. The x-ray pulses are shown in pink, and the blue features are ultraviolet aurorae.

X-Ray EmissionsX-Ray Emissions

• This composite was taken by the Chandra Observatory. When they looked at this radio arc (in red), they observed an x-ray-emitting cloud about 40 light-years wide (blue). These x-ray-emissions are caused when electrons from radio filaments collide with a cloud of cold gas with a mass millions of times greater than our sun’s.

X-ray view of the Milky Way center

X-ray view of the Milky Way center

• This is a mosaic of 30 Chandra images. The Milky Way is home to more than a thousand white dwarfs, neutron stars and black holes. If you possessed x-ray vision, you would be able to see this image instead of the massive cosmic dust clouds.

Black HolesBlack Holes

• Here is a composite of the black hole XTE J118+480 taken by the Chandra Observatory. It is seven times more massive than our sun, and takes material from an orbiting solar-type star, and uses that material to create bursts of x-rays. Its x-ray spectrum is shown from the upper left corner to the lower right.

Venus in X-rayVenus in X-ray

• The picture shown on the left is the first ever photo taken of Venus in the x-ray spectrum. The traditional optical view of Venus is shown on the right, and can be seen through a telescope. Venus’ x-rays are produced by fluorescence rather than reflection. Incoming solar x-rays excite atoms in Venus’ atmosphere,

and these atoms emit a fluorescence x-ray, creating the glowing effect seen on the left.

Jupiter’s Great X-ray SpotJupiter’s Great X-ray Spot

• The X-ray spots shown on the poles of Jupiter are just as surprising to astronomers today as the Great Red Spot once was. The false-color image is shown on the right and Jupiter’s x-ray emissions can be seen on the left, taken by the Chandra Observatory.

BibliographyBibliography

• http://chandra.harvard.edu/about/top_ten.html• http://imagers.gsfc.nasa.gov/ems/xrays.html

• www.astronomy.com• http://antwrp.gsfc.nasa.gov/apod/astropix.html

• “Electromagnetic Radiation” The Visual Encyclopedia of the Universe

• “X-ray” World Book Encyclopedia