Calendar

Moon at Apogee

The Moon’s distance from Earth varies throughout its monthly orbit because the Moon’s orbit isn’t perfectly circular. Every month, the Moon’s eccentric orbit carries it to apogee – its most distant point from Earth – and then, some two weeks later, to perigee – the Moon’s closest point to Earth in its monthly orbit. - earthsky.org

Sir W. Lawrence Bragg, FRS, shared Nobel Prise with his father for X-ray crystallography (d. 1971)

Sir William Lawrence Bragg was an Australian-born British physicist and X-ray crystallographer, discoverer (1912) of Bragg's law of X-ray diffraction, which is basic for the determination of crystal structure. He was joint recipient (with his father, William Henry Bragg) of the Nobel Prize in Physics in 1915, "For their services in the analysis of crystal structure by means of X-rays"; an important step in the development of X-ray […]

New Moon

New Moon. By the modern definition, New Moon occurs when the Moon and Sun are at the same geocentric ecliptic longitude. The part of the Moon facing us is completely in shadow then. Pictured here is the traditional New Moon, the earliest visible waxing crescent, which signals the start of a new month in many […]

Mars at Aphelion

Mars will be at the farthest point in its orbit around the Sun on this date - 154,425,919.9 miles.  

G. Lippmann, Nobel Prize for optics, (d. 1921)

Jonas Ferdinand Gabriel Lippmann (16 August 1845 – 13 July 1921) was a Franco-Luxembourgish physicist and inventor, and Nobel laureate in physics for his method of reproducing colours photographically based on the phenomenon of interference. - Wikipedia

LunGradCon

Online

Macke R. J., Opeil C. P., Britt D. T., and Consolmagno G. J. will discuss "Thermal Properties of Lunar Material in Permanently Shadowed Regions" at the  2021 NASA Exploration Science Forum & European Lunar Symposium. Session date and time TBD.