2011 Calendar of Astronomical Events




    


2011 Phases of the Moon

Mountain Standard 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.

2011 Phases of the Moon
Mountain Standard Time
New Moon First Quarter Full Moon Last Quarter
Jan 4 02:03 P Jan 12 04:31 Jan 19 14:21 Jan 26 05:57
Feb 2 19:31 Feb 11 00:18 Feb 18 01:36 Feb 24 16:26
Mar 4 13:46 Mar 12 16:45 Mar 19 11:10 Mar 26 05:07
Apr 3 07:32 Apr 11 05:05 Apr 17 19:44 Apr 24 19:47
May 2 23:51 May 10 13:33 May 17 04:09 May 24 11:52
Jun 1 14:03 P Jun 8 19:11 Jun 15 13:13 t Jun 23 04:48
Jul 1 01:54 P Jul 7 23:29 Jul 14 23:40 Jul 22 22:02
Jul 30 11:40 Aug 6 04:08 Aug 13 11:58 Aug 21 14:55
Aug 28 20:04 Sep 4 10:39 Sep 12 02:27 Sep 20 06:39
Sep 27 04:09 Oct 3 20:15 Oct 11 19:06 Oct 19 20:30
Oct 26 12:56 Nov 2 09:38 Nov 10 13:16 Nov 18 08:09
Nov 24 23:10 P Dec 2 02:52 Dec 10 07:36 t Dec 17 17:48
Dec 24 11:06 ---

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.



2011 Calendar of Astronomical Events

Mountain Standard Time

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

2011 Calendar of Astronomical Events
January - June July - December
Date     MST   Event
        (h:m)

Jan 01  11:07  Antares 2.5°S of Moon
    02  07:32  Mercury 3.8°N of Moon
    03  05:48  Moon at Ascending Node 
    03  12     Earth at Perihelion: 0.98334 AU
    03  18     Quadrantid Meteor Shower
    04  01:51  Partial Solar Eclipse; mag=0.858
    04  02:03  NEW MOON 
    08  08     Venus at Greatest Elong: 47.0°W
    09  07     Mercury at Greatest Elong: 23.3°W
    09  22:38  Moon at Apogee: 404976 km
    12  04:31  FIRST QUARTER MOON 
    15  05:39  Pleiades 1.3°N of Moon
    17  17:06  Moon at Descending Node 
    19  14:21  FULL MOON 
    21  17:10  Moon at Perigee: 362793 km
    21  18:55  Regulus 5.3°N of Moon
    25  10:38  Spica 3.0°N of Moon
    26  05:57  LAST QUARTER MOON 
    28  16:53  Antares 2.6°S of Moon
    29  20:36  Venus 3.5°N of Moon
    30  11:29  Moon at Ascending Node 
    31  02     Mercury at Aphelion 

Feb 01  11:14  Mercury 3.6°S of Moon
    02  19:31  NEW MOON 
    04  10     Mars in Conjunction with Sun 
    06  16:13  Moon at Apogee: 405924 km
    11  00:18  FIRST QUARTER MOON 
    11  14:32  Pleiades 1.4°N of Moon
    14  01:14  Moon at Descending Node 
    17  02     Neptune in Conjunction with Sun 
    18  01:36  FULL MOON 
    18  05:18  Regulus 5.2°N of Moon
    19  00:27  Moon at Perigee: 358247 km
    21  18:02  Spica 2.8°N of Moon
    24  16:26  LAST QUARTER MOON 
    24  22:26  Antares 2.8°S of Moon
    25  01     Mercury at Superior Conjunction 
    26  13:19  Moon at Ascending Node 
    28  20:40  Venus 1.6°S of Moon

Mar 04  13:46  NEW MOON 
    06  00:50  Moon at Apogee: 406584 km
    09  05     Mars at Perihelion 
    10  21:35  Pleiades 1.7°N of Moon
    12  16:45  FIRST QUARTER MOON 
    13  04:55  Moon at Descending Node 
    15  13     Mercury 2.0° of Jupiter
    16  01     Mercury at Perihelion 
    16  04     Jupiter at Perihelion 
    17  16:35  Regulus 5.3°N of Moon
    19  11:10  FULL MOON 
    19  12:09  Moon at Perigee: 356578 km
    20  16:21  Vernal Equinox 
    21  04:00  Spica 2.6°N of Moon
    21  05     Uranus in Conjunction with Sun 
    22  18     Mercury at Greatest Elong: 18.6°E
    24  05:48  Antares 3.0°S of Moon
    25  14:09  Moon at Ascending Node 
    26  05:07  LAST QUARTER MOON 

Apr 02  02:00  Moon at Apogee: 406656 km
    03  07:32  NEW MOON 
    03  16     Saturn at Opposition 
    06  08     Jupiter in Conjunction with Sun 
    07  03:19  Pleiades 1.9°N of Moon
    09  05:48  Moon at Descending Node 
    09  12     Mercury at Inferior Conjunction 
    11  05:05  FIRST QUARTER MOON 
    14  02:34  Regulus 5.5°N of Moon
    16  22:59  Moon at Perigee: 358088 km
    17  15:04  Spica 2.5°N of Moon
    17  19:44  FULL MOON 
    18  17     Venus at Aphelion 
    19  11     Mercury 0.6° of Mars
    20  15:21  Antares 3.2°S of Moon
    21  18:05  Moon at Ascending Node 
    22  16     Lyrid Meteor Shower
    24  19:47  LAST QUARTER MOON 
    29  11:02  Moon at Apogee: 406043 km

May 02  23:51  NEW MOON 
    05  05     Eta-Aquarid Meteor Shower
    06  07:54  Moon at Descending Node 
    07  12     Mercury at Greatest Elong: 26.6°W
    07  22     Mercury 1.4° of Venus
    10  13:33  FIRST QUARTER MOON 
    11  10:05  Regulus 5.7°N of Moon
    11  13     Mercury 2.1° of Jupiter
    15  01:08  Spica 2.6°N of Moon
    15  04:18  Moon at Perigee: 362133 km
    17  04:09  FULL MOON 
    18  00     Mercury 1.4° of Venus
    18  01:46  Antares 3.3°S of Moon
    19  02:03  Moon at Ascending Node 
    21  01     Mercury 2.1° of Mars
    24  11:52  LAST QUARTER MOON 
    27  02:58  Moon at Apogee: 405006 km
    29  07:31  Jupiter 5.7°S of Moon
    30  13:04  Mars 3.8°S of Moon
    30  21:00  Venus 4.4°S of Moon

Jun 01  14:03  NEW MOON 
    01  14:16  Partial Solar Eclipse; mag=0.601
    02  13:21  Moon at Descending Node 
    07  15:45  Regulus 5.7°N of Moon
    08  19:11  FIRST QUARTER MOON 
    09  07:50  Venus 5.0°S of Pleiades
    11  08:57  Spica 2.6°N of Moon
    11  18:42  Moon at Perigee: 367188 km
    12  01     Mercury at Perihelion 
    12  16     Mercury at Superior Conjunction 
    14  11:17  Antares 3.3°S of Moon
    15  11:35  Moon at Ascending Node 
    15  13:13  Total Lunar Eclipse; mag=1.700
    15  13:13  FULL MOON 
    17  05:15  Venus 4.6°N of Aldebaran
    20  18:24  Mars 4.2°S of Pleiades
    21  10:16  Summer Solstice 
    23  04:48  LAST QUARTER MOON 
    23  21:13  Moon at Apogee: 404275 km
    26  01:45  Jupiter 5.4°S of Moon
    27  23:52  Pleiades 2.0°N of Moon
    28  00:40  Mercury 4.7°S of Pollux
    28  11:59  Mars 1.7°S of Moon
    29  21:14  Moon at Descending Node 

Date     MST   Event
        (h:m)

Jul 01  01:38  Partial Solar Eclipse; mag=0.097
    01  01:54  NEW MOON 
    02  19:11  Mercury 5.1°N of Moon
    04  08     Earth at Aphelion: 1.01674 AU
    04  12:18  Mars 5.4°N of Aldebaran
    04  21:23  Regulus 5.7°N of Moon
    06  10:36  Mercury 0.2°S of Beehive
    07  07:04  Moon at Perigee: 369566 km
    07  23:29  FIRST QUARTER MOON 
    08  14:44  Spica 2.6°N of Moon
    11  18:48  Antares 3.3°S of Moon
    12  19:27  Moon at Ascending Node 
    14  23:40  FULL MOON 
    19  22     Mercury at Greatest Elong: 26.8°E
    21  15:46  Moon at Apogee: 404358 km
    22  22:02  LAST QUARTER MOON 
    23  17:34  Jupiter 5.1°S of Moon
    25  08:28  Pleiades 2.1°N of Moon
    26  00     Mercury at Aphelion 
    26  05:51  Mercury 2.1°S of Regulus
    27  05:03  Moon at Descending Node 
    27  09:52  Mars 0.5°N of Moon: Occn.
    28  07     Delta-Aquarid Meteor Shower
    30  11:40  NEW MOON 

Aug 01  04:20  Mercury 1.5°N of Moon
    01  04:41  Regulus 5.6°N of Moon
    02  13:59  Moon at Perigee: 365756 km
    04  20:08  Spica 2.4°N of Moon
    06  04:08  FIRST QUARTER MOON 
    08  00:32  Antares 3.5°S of Moon
    08  23:35  Moon at Ascending Node 
    09  01     Venus at Perihelion 
    12  23     Perseid Meteor Shower
    13  11:58  FULL MOON 
    16  05     Venus at Superior Conjunction 
    16  18     Mercury at Inferior Conjunction 
    18  09:23  Moon at Apogee: 405161 km
    20  05:13  Jupiter 4.8°S of Moon
    21  14:55  LAST QUARTER MOON 
    21  16:40  Pleiades 2.3°N of Moon
    22  15     Neptune at Opposition 
    23  10:23  Moon at Descending Node 
    25  06:36  Mars 2.7°N of Moon
    27  18:07  Mercury 2.6°N of Moon
    28  20:04  NEW MOON 
    30  10:35  Moon at Perigee: 360858 km

Sep 01  03:06  Spica 2.2°N of Moon
    02  23     Mercury at Greatest Elong: 18.1°W
    04  06:00  Antares 3.7°S of Moon
    04  10:39  FIRST QUARTER MOON 
    05  00:36  Moon at Ascending Node 
    08  00     Mercury at Perihelion 
    08  01:45  Mars 5.8°S of Pollux
    08  19:18  Mercury 0.6°N of Regulus
    12  02:27  FULL MOON 
    14  23:23  Moon at Apogee: 406068 km
    16  11:20  Jupiter 4.7°S of Moon
    17  23:46  Pleiades 2.5°N of Moon
    19  12:38  Moon at Descending Node 
    20  06:39  LAST QUARTER MOON 
    23  01:23  Mars 4.8°N of Moon
    23  02:05  Autumnal Equinox 
    25  00:49  Regulus 5.7°N of Moon
    25  17     Uranus at Opposition 
    27  04:09  NEW MOON 
    27  18:01  Moon at Perigee: 357556 km
    28  13     Mercury at Superior Conjunction 
    30  17:53  Mars 0.4°S of Beehive

Oct 01  13:04  Antares 3.9°S of Moon
    02  02:09  Moon at Ascending Node 
    03  20:15  FIRST QUARTER MOON 
    11  19:06  FULL MOON 
    12  04:43  Moon at Apogee: 406435 km
    13  12:28  Jupiter 4.8°S of Moon
    13  14     Saturn in Conjunction with Sun 
    15  05:49  Pleiades 2.7°N of Moon
    16  14:01  Moon at Descending Node 
    19  20:30  LAST QUARTER MOON 
    21  15     Orionid Meteor Shower
    22  10:52  Regulus 5.8°N of Moon
    26  05:26  Moon at Perigee: 357051 km
    26  12:56  NEW MOON 
    27  19:14  Mercury 0.2°N of Moon: Occn.
    27  22:11  Venus 1.8°N of Moon
    28  18     Jupiter at Opposition 
    28  22:37  Antares 4.1°S of Moon
    29  07:59  Moon at Ascending Node 

Nov 01  13     Mercury 2.0° of Venus
    02  09:38  FIRST QUARTER MOON 
    05  15     S Taurid Meteor Shower
    08  06:20  Moon at Apogee: 406177 km
    09  11:40  Jupiter 5.0°S of Moon
    10  00:51  Venus 3.8°N of Antares
    10  01:27  Mercury 1.9°N of Antares
    10  11:21  Mars 1.3°N of Regulus
    10  13:16  FULL MOON 
    11  04:32  Saturn 4.0°N of Spica
    11  11:43  Pleiades 2.8°N of Moon
    12  10:18  Aldebaran 5.9°S of Moon
    12  15     N Taurid Meteor Shower
    12  17:35  Moon at Descending Node 
    13  01     Mercury 2.0° of Venus
    14  02     Mercury at Greatest Elong: 22.7°E
    17  21     Leonid Meteor Shower
    18  08:09  LAST QUARTER MOON 
    18  18:42  Regulus 6.0°N of Moon
    22  10:21  Spica 2.1°N of Moon
    23  16:24  Moon at Perigee: 359692 km
    24  23:10  NEW MOON 
    24  23:20  Partial Solar Eclipse; mag=0.905
    25  18:02  Moon at Ascending Node 
    26  02:48  Mercury 1.7°S of Moon
    26  21:29  Venus 2.8°S of Moon

Dec 02  02:52  FIRST QUARTER MOON 
    04  02     Mercury at Inferior Conjunction 
    04  23     Mercury at Perihelion 
    05  18:13  Moon at Apogee: 405414 km
    06  13:10  Jupiter 5.2°S of Moon
    08  18:26  Pleiades 2.8°N of Moon
    09  16:51  Aldebaran 5.9°S of Moon
    10  00:04  Moon at Descending Node 
    10  07:32  Total Lunar Eclipse; mag=1.106
    10  07:36  FULL MOON 
    14  10     Geminid Meteor Shower
    16  00:26  Regulus 6.0°N of Moon
    17  17:48  LAST QUARTER MOON 
    19  18:37  Spica 2.1°N of Moon
    21  19:56  Moon at Perigee: 364801 km
    21  22:30  Winter Solstice 
    22  19     Ursid Meteor Shower
    22  20     Mercury at Greatest Elong: 21.8°W
    22  20:05  Antares 4.1°S of Moon
    22  20:50  Mercury 2.6°N of Moon
    23  04:36  Moon at Ascending Node 
    24  03:36  Mercury 6.3°N of Antares
    24  11:06  NEW MOON 

    

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



Calendars for Other Years and Time Zones

The table below contains links to astronomical events calendars for a range of years and Time Zones. Abbreviations for the time zones are: GMT = Greenwich Mean Time, AST = Atlantic Standard Time, EST = Eastern Standard Time, CST = Central Standard Time, MST = Mountain Standard Time, PST = Pacific Standard Time, AKST = Alaskan Standard Time, and HST = Hawaiian Standard Time.

Calendar of Astronomical Events
GMT 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
AST 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
EST 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
CST 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
MST 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
PST 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
AKST 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
HST 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025

For years or time zones not covered above, please visit SKYCAL the astronomical events calendar generator.

Accuracy

The times of astronomical events listed with a precision in hours and minutes (i.e., hh:mm) are accurate to the nearest minute. Similarly, the times of astronomical events listed with a precision in hours (i.e., hh) are accurate to the nearest hour.

A simplified solar ephemeris results an accuracy of ±0.5 hours for the perihelion and aphelion of Earth. The algorithm used in the perihelion and aphelion of the other planets is based on unperturbed elliptical orbits. For Mars, the accuracy is about 2 hours. Due to mutual planetary perturbations, the times for Jupiter may be in error by several weeks, while Saturn's times may be in error by a month. The times for Uranus and Neptune may be in error by several months. In the future, we plan to develop algorithms to improve the computed times of perihelion and aphelion of the planets.

Acknowledgements

All calculations are by Fred Espenak, and he assumes full responsibility for their accuracy. Algorithms used in predicting the phases of the Moon, eclipses and other sky phenomena are based on Astronomical Algorithms by Jean Meeus (Willmann-Bell, Inc., Richmond, 1998).

Permission is freely granted to reproduce this data when accompanied by the acknowledgment:


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