Added 1 new A* page:"China to relocate 10,000 people to make way for telescope" said the BBC last week: China wants to clear a 5 kilometer radius around the site of their planned 500m-wide radio telescope to reduce potential interference from terrestrial sources. They say the radio telescope, which will be way larger than the current largest, a 300m radio telescope in Puerto Rico, will be used to help search for extraterrestrial life; radio telescopes are also pretty good for looking at the galactic core where A* is, though, though, because radio wavelengths, longer than visible wavelengths and thus more leisurely in their vibrations, slip between particles of interstellar dust more readily than more energetic parts of the electromagnetic spectrum, and thus have a greater chance of reaching the Earth for us to see—and there's an awful lot of dust between us and the core.
If you want to know more about radio telescopes, well it just so happens that in the past week I came across this little one-page edutainment story in Charlton Comics' Space Adventures #15 from March, 1955 (artist and writer unknown):
Boy, with a 500m 'scope, China will be able to pick up those hostile space fleets from the Moon really easy! A*, though, would not have been one of the observed "stars" "emitting high frequency radiation" back then—its radio signal wasn't identified until 1974 (hey that's the year I was born—-HMMM!), by Bruce Balick and Robert Brown; "The name Sgr A* was coined by Brown in a 1982 paper because the radio source was 'exciting', and excited states of atoms are denoted with asterisks" (from Wikipedia). Earlier names for A* from others, that didn't stick, included "GCCRS" ("Galactic Center Compact Radio Source") and "Sgr A(cn)" (for "Compact Non-thermal"); you can read about those in "The Discovery of Sgr A*," Brown and others' rather exciting scientific account of the four-year search for the black hole at the center of our galaxy after a chance detection of a radio source there in 1970.
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