Editing 1899 in science (section)

==Astronomy and space sciences==
* March 18 – [[Phoebe (moon)|Phoebe]], the ninth-known moon of the planet [[Saturn]] is discovered by U.S. astronomer [[William Henry Pickering|William H. Pickering]] from analysis of photographic plates made by a Peruvian observatory seven months earlier, the first discovery of a satellite photographically.
* April 21 – The [[nova]] [[V606 Aquilae]] is first observed from Earth as seen within the [[constellation]] [[Aquila (constellation)|Aquila]]. It fades within six months.
* October 19 – 17-year-old [[Robert H. Goddard]] in Worcester, Massachusetts, receives his inspiration to develop a rocket capable of reaching outer space, after viewing his yard from high in a tree and imagining "how wonderful it would be to make some device which had even the possibility of ascending to Mars, and how it would look on a small scale, if sent up from the meadow at my feet."<ref>{{cite book|first=Milton|last=Lehman|title=Robert H. Goddard: Pioneer of Space Research|publisher=Da Capo Press|year=1988|page=16}}</ref>
* December 2 – During the [[new moon]], a near-grand [[Conjunction (astronomy and astrology)|conjunction]] of the [[naked-eye planet|classical planets]] and several [[binoculars|binocular]] [[Solar System]] bodies occur. The Sun, Moon, [[Mercury (planet)|Mercury]], [[Mars]] and [[Saturn]] are all within 15° of each other, with [[Venus]] 5° ahead of this conjunction and [[Jupiter]] 15° behind. Accompanying the classical planets in this grand conjunction are [[Uranus]] (technically visible unaided in [[air pollution|pollution]]-free skies), [[Ceres (dwarf planet)|Ceres]] and [[2 Pallas|Pallas]].
* The 80&nbsp;cm [[refracting telescope]] is completed at [[Potsdam Observatory]].