In 1951, Fred Whipple suggested that the nucleus of a comet was like a dirty Snowball, consisting of ices of water, ammonia (NH3), and methane (CH4), with grains of embedded meteoric material. Did the nucleus of a comet look like a ...
Whipple's dirty snowball would have an albedo higher than either of these estimates , so was it correct ? Prior to the Halley spacecraft encounters , no - one had imaged the nucleus of a comet nor knew its size for certain .
Gorbachev , Mikhail S. , 21n Gorenstein , P. , 343 Greenstein , Jesse L. , 331 , 424 , 425 Gregory , 346 Gregory , Philip ... Robert , 352 Hearn , 324 Heise , John , 318 Helfand , David J. , 342 , 407 , 408 Herbig , George , 451 Herman ...
New Cosmic Horizons tells the extraordinary story of space-based astronomy since the Second World War.
The history of astronomy is, like most history, a multidimensional story, and when writing about a specific period, the author has to decide how to handle all the developments of...
These are followed by articles on tools and techniques, from the history of spectroscopy to adaptive optics.