Radiation astronomy/Radios/Lessons

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The quiet Sun at 4.6 GHz imaged by the VLA with a resolution of 12 arcsec, or about 8400 km on the surface of the Sun. Credit: NRAO.

Radio astronomy encompasses microwave astronomy, submillimeter astronomy, and those bands with longer wavelengths than microwaves. Radar astronomy is a technological use of microwaves to locate rocky objects.

There are 89 unique areas of the celestial sphere from which radio waves can irradiate the Earth. Ideally, there would be a first source from each of these areas.

As radio astronomy has been in use since the early twentieth century, a radio source has a good chance of also being a first source for any constellation.

The first radio source in any region of the sky is usually unknown. The discoverer often notes the source in passing.

These are lessons in map reading, coordinate matching, and researching looking for the first astronomical radio source discovered in the constellation of interest.

First steps[edit]

The first step is to succeed in finding a radio source in the constellation. This is usually not easy. One way is to search Google images, or Commons.

Sources[edit]

This composite picture shows the radio sky above an old optical photograph of the NRAO site in Green Bank, WV. Credit: NRAO.

Def. a natural source usually of radiation in the sky especially at night is called an astronomical source.

A source of astronomical information on older detections of radio sources may be included in the Science section of the lecture/article radio astronomy.

Traveling radio sources[edit]

Many radio sources do not remain in a constellation for lengthy periods. Some of these are the Sun and sources apparently in orbit around the Sun. The Sun travels through the 13 constellations along the ecliptic (the plane of the Earth's orbit around the Sun): the 12 of the Zodiac and the constellation Ophiuchus. These are described in source astronomy.

Backgrounds[edit]

To introduce yourself to some aspects of the challenge may I suggest reading the highlighted links mentioned above, and if you're curious, those listed under the section See also below. Sources of interest can occur in the background of other sources.

Radio waves are a form of radiation that is currently part of electromagnetic radiation intersecting the Earth. More information about radiation is in radiation astronomy.

Constellations[edit]

Constellations of the past can be found in astrohistory.

Searching catalogs[edit]

In the lecture/article radio astronomy in its science section is a list of older catalogs of radio sources. Using the constellation description in the previous section and the range of coordinates for the constellation in source astronomy, scan through the coordinates for these radio sources to see if any may be within the constellation. An example is "A Catalog of 1.4 GHz Radio Sources from the FIRST Survey", a catalog of 138,665 radio sources.[1]

Radio lessons[edit]

Microwave lessons[edit]

Submillimeter lessons[edit]

Hypotheses[edit]

  1. The first radio source was detected in a northern hemisphere constellation.

See also[edit]

References[edit]

  1. Richard L. White, Robert H. Becker, David J. Helfand, and Michael D. Gregg (1997). "A Catalog of 1.4 GHz Radio Sources from the FIRST Survey". The Astrophysical Journal 475 (2): 479. doi:10.1086/303564. http://first.astro.columbia.edu/first/postscript/catalog_paper.ps.Z. Retrieved 2016-11-21. 

External links[edit]