2017 Calendar of Astronomical Events

2017 Phases of the Moon

Greenwich Mean Time

The following table gives the date and time of the Moon's phases for the year. If Daylight Saving Time is in effect, add one hour to the times listed.

An eclipse of the Sun can only occur at New Moon (see: Solar Eclipses for Beginners), while an eclipse of the Moon can only occur at Full Moon (see: Lunar Eclipses for Beginners). In any calendar year there are a minimum of two solar and two lunar eclipses.

If an eclipse of the Sun or Moon takes place on a given date, it is noted by a character next to the date in the table above. Solar eclipses are indicated as: T=Total, A=Annular, H=Hybrid and P=Partial. Lunar eclipses are indicated as: t=Total, p=Partial, and n=Penumbral.

Phases of the Moon Photo Gallery is an image collection showing the Moon's phases over a complete synodic month.

2017 Calendar of Astronomical Events

Greenwich Mean Time

The following table gives the date and time of the important astronomical events for the year. If Daylight Saving Timeis in effect, add one hour to the times listed. A key to astronomical terms appears below the calendar.

Astronomical Definitions

• Perihelion - the instant when a planet is closest to the Sun
• Aphelion - the instant when a planet is furthest from the Sun
• Perigee - the instant when the Moon is closest to Earth
• Apogee - the instant when the Moon is furthest from Earth
• Inferior Conjunction - the instant when a planet passes between Earth and the Sun (Mercury or Venus)
• Superior Conjunction - the instant when a planet passes on the opposite side of the Sun from Earth (Mercury or Venus)
• Greatest Elongation - elongation is the apparent angle between a planet and the Sun as seen from Earth; during eastern elongation (E), the planet appears as an evening star; during western elongation (W), the planet appears as a morning star
• Opposition - the instant when a planet appears opposite the Sun as seen from Earth
• Conjunction - the instant when a planet appears closest the Sun as seen from Earth
• Occultation - the Moon occults or eclipses a star or planet
• Ascending Node - the point where a planet crosses from the southern to northern portion of its orbit
• Descending Node - the point where a planet crosses from the northern to the southern portion of its orbit

Fuentes: Astropixels