Astronomy Picture of the Day 16 Jul 06

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Astronomy Picture of the Day 16 Jul 06 The
center of our Galaxy is a busy place. In visible
light, much of the Galactic Center is obscured by
opaque dust. In infrared light, however, dust
glows more and obscures less, allowing nearly one
million stars to be recorded in the above
photograph. The Galactic Center itself appears on
the right and is located about 30,000 light years
away towards the constellation of Sagittarius.
The Galactic Plane of our Milky Way Galaxy, the
plane in which the Sun orbits, is identifiable by
the dark diagonal dust lane. The absorbing dust
grains are created in the atmospheres of cool
red-giant stars and grow in molecular clouds. The
region directly surrounding the Galactic Center
glows brightly in radio and high-energy
radiation, and is thought to house a large black
hole. taken from http//antwrp.gsfc.nasa.gov/ap
od/ap060716.html
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REU Summer 2006 KSU SRT Project

• Ashley K. Wheeler
• Mentor Dr. Tim Bolton

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Outline

• Why radio astronomy?
• What is radio astronomy?
• Versus optical astronomy?
• How are radio waves emitted?
• Basic Schematic
• Resolution
• Summary, pre-REU

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Outline, cont.

• REU
• Software
• Sweeps/ Waveforms
• Aliasing
• What is it?
• Why is it a problem?
• Data Comparison
• Baselines and Averaging
• Possible Sources

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Outline, cont.

• Whats next?
• Software
• Mounting
• For More Information

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Why radio astronomy?

• What is radio astronomy?
• Versus optical astronomy?

figure borrowed from http//www.disp.duke.edu/db
rady/ece371/notes/l2/spectrum.html
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How are radio waves emitted?

• Black bodies
• Ionized gas clouds
• Change in energy states and masers
• Electron plus magnetic field (non-thermal)
• Moving magnetic field (non-thermal)

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Basic Schematic
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Resolution

• q 1.03l/D 1.03(c/n)/D
• 0.02575 radians, or about 1.5 degrees

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Summary, pre-REU

• Sat finders and tees

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REU

• CNVTWFM
• Moved the dish outside
• 1st sweep Jun 20th, 2006

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REU, cont.
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REU, cont.

• Aliasing

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REU, cont.

• Data comparison

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REU, cont.

• Baselines and averaging

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REU, cont.

• Manhattan, KS 39.179642 -gt dec. of 39o 10
  46.7112
• RA (our time of day) (5 hrs)

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Next, cont.

• Signal processing software
• Mounting?

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For More Information

• The Astronomical Almanac
• www.radio.uindy.edu
• www.nrao.edu/epo/amateur
• www.wikipedia.org
• www.bambi.net