First Quarter Moon
The Moon is at First quarter on this date -it will be visible high in the southern sky in early evening.
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.
Last Quarter Moon
The Moon is at Last Quarter (or Third Quarter) – rising around midnight, and visible to the south after sunrise.
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 […]
Eta-Aquariid Meteor Shower
The Eta Aquariids are a strong shower when viewed from the southern tropics. From the equator northward, they usually only produce medium rates of 10-30 per hour just before dawn. […]
The summer solstice is the day when the Sun appears to reach its highest point in the sky during the year - it marks the start of summer in the Northern Hemisphere.
International Asteroid Day
International Asteroid Day is a United Nations-recognized day observed each year on the anniversary of the Tunguska impact event of June 30, 1908.
Delta-Aquariids Meteor Shower
The Delta Aquariids are active beginning in mid-July and are visible until late-August. These faint meteors are difficult to spot, and if there is a moon you will not be […]
Mercury at Aphelion
Mercury's 88-day orbit around the Sun will carry it to its furthest point to the Sun – its aphelion – at a distance of 0.47 AU.
Perseids Meteor Shower
The Perseids are the most popular meteor shower as they peak on warm August nights as seen from the northern hemisphere. The Perseids are active from July 17 to August 24, peaking on August 12 - 13.
Ursids Meteor Shower
The Ursids peak just before Christmas with rates of 5-10 meteors per hour during the late morning hours.
The winter solstice, also called the hibernal solstice, occurs when either of Earth's poles reaches its maximum tilt away from the Sun.