Astro Blog

Source:   Writer's Almanac Excerpt: ...Before he made his discovery, everyone thought that our Milky Way galaxy was the only galaxy in the universe, and that there wasn’t much outside it besides the Magellanic Clouds, which are visible by the naked eye in the Southern Hemisphere, and which were thought to be clouds of gas or dust. ...Hubble first published his discovery in a paper called “Extragalactic Nature of Spiral Nebulae,” which was presented on this date, in his absence, at a joint meeting of the American Astronomical Society and the American Association for the Advancement of Science. ...Hubble had written his doctoral dissertation on “Photographic Investigations of Faint Nebulae.” With older or smaller telescopes, nebulae just looked like clouds of glowing gas, but with the Hooker telescope — the most powerful telescope in the world at that time — Hubble was able to see that there were actually stars within the nebula. One of the stars in the Andromeda Nebula turned ou

Source:   By National Radio Astronomy Observatory Excerpt: Astronomers now know that our galaxy is teeming with planets, from rocky worlds roughly the size of Earth to gas giants bigger than Jupiter. Nearly every one of these exoplanets has been discovered in orbit around a mature star with a fully evolved planetary system. New observations with the Atacama Large Millimeter/submillimeter Array (ALMA) contain compelling evidence that two newborn planets, each about the size of Saturn, are in orbit around a young star known as HD 163296. These planets, which are not yet fully formed, revealed themselves by the dual imprint they left in both the dust and the gas portions of the star’s protoplanetary disk. [see image https://public.nrao.edu/wp-content/uploads/2016/12/imagespr2016cbnrao16cb25nrao16cb25a_nrao-1170x600.jpg ]... https://public.nrao.edu/news/2016-alma-planets-disk/