Calendar

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 […]

V. Ambartsumian, theoretical astrophysicist, d. 1996

Viktor Amazaspovich Ambartsumian was a Soviet Armenian astrophysicist and science administrator. One of the 20th century's top astronomers, he is widely regarded as the founder of theoretical astrophysics in the Soviet Union.

Moon at Perigee

Every month, the Moon’s eccentric orbit carries it to perigee, the Moon’s closest point to Earth in its orbit – then 2 weeks later, to apogee, its most distant point from Earth.

Conjunction of Mercury and Mars

Mars and Mercury will be less than a degree apart in the sky - this may be VERY difficult to view with the naked eye due to their proximity to […]

Jupiter at Opposition

Jupiter will be in opposition to the Sun on this date; this is when the Earth is positioned between the Sun and Jupiter.

Full Moon

The Full Moon rises at sunset, and is visible all night. The Vatican Observatory's monthly Full Moon Meetup for Sacred Space Astronomy subscribers is held at 10:00 AM Tucson time.