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 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 […]

Partial Solar Eclipse

On Saturday, April 30, 2022, people in parts of southern South America, Antarctica, and the Pacific and Southern Oceans will have a chance to witness a partial eclipse of the Sun just before and during sunset.

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. Activity is good for a week centered the night of maximum activity. These are swift meteors that produce a high percentage of persistent trains, but […]

Cinco de Mayo

Mother's Day in the United States is an annual holiday celebrated on the second Sunday in May. Mother's Day recognizes mothers, motherhood and maternal bonds in general, as well as the positive contributions that they make to society. It was established by Anna Jarvis, with the first official Mother's Day celebrated through a service of worship at St. Andrew's Methodist […]

Astronomy Day

Astronomy Day is an international event observed each fall and spring near the first quarter Moon. Local astronomical societies, planetariums, museums, and observatories sponsor public viewing sessions, presentations, workshops, and other activities to increase public awareness about astronomy and our wonderful universe.

Mother’s Day (USA)

Mother's Day in the United States is an annual holiday celebrated on the second Sunday in May. Mother's Day recognizes mothers, motherhood and maternal bonds in general, as well as the positive contributions that they make to society. It was established by Anna Jarvis, with the first official Mother's Day celebrated through a service of worship at St. Andrew's Methodist […]

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.

World Metrology Day.

World Metrology Day is an annual celebration of the signature of the Metre Convention on 20 May 1875 by representatives of seventeen nations. The Convention set the framework for global collaboration in the science of measurement and in its industrial, commercial and societal applications. The original aim of the Metre Convention - the world-wide uniformity […]