2011Calendar of Astronomical Events

    
2011Phases of the Moon
Pacific Standard Time
The following table gives the date and time of the Moon's phases for the year. The times listed are for Pacific Standard Time(Greenwich Mean Time - 8 hours).If Daylight Saving Time is in effect, add one hour to the times listed. 
   
      2011 Phases of the Moon   
      Pacific Standard Time
 New Moon  First Quarter  Full Moon  Last Quarter 
 Jan  4  01:03 P  Jan 12  03:31    Jan 19  13:21    Jan 26  04:57   
 Feb  2  18:31    Feb 10  23:18    Feb 18  00:36    Feb 24  15:26   
 Mar  4  12:46    Mar 12  15:45    Mar 19  10:10    Mar 26  04:07   
 Apr  3  06:32    Apr 11  04:05    Apr 17  18:44    Apr 24  18:47   
 May  2  22:51    May 10  12:33    May 17  03:09    May 24  10:52   
 Jun  1  13:03 P  Jun  8  18:11    Jun 15  12:13 t  Jun 23  03:48   
 Jul  1  00:54 P  Jul  7  22:29    Jul 14  22:40    Jul 22  21:02   
 Jul 30  10:40    Aug  6  03:08    Aug 13  10:58    Aug 21  13:55   
 Aug 28  19:04    Sep  4  09:39    Sep 12  01:27    Sep 20  05:39   
 Sep 27  03:09    Oct  3  19:15    Oct 11  18:06    Oct 19  19:30   
 Oct 26  11:56    Nov  2  08:38    Nov 10  12:16    Nov 18  07:09   
 Nov 24  22:10 P  Dec  2  01:52    Dec 10  06:36 t  Dec 17  16:48   
 Dec 24  10:06   ---
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.
2011Calendar of Astronomical Events
Pacific Standard Time
The following table gives the date and time of the important astronomical events for the year. The times listed are for Pacific Standard Time(Greenwich Mean Time - 8 hours).If Daylight Saving Time is in effect, add one hour to the times listed. A key to astronomical terms appears below the calendar.
   
      2011Calendar of Astronomical Events   
   Pacific Standard Time  
 January - June   July - December 
Date     PST   Event        (h:m)Jan 01  10:07  Antares 2.5°S of Moon    02  06:32  Mercury 3.8°N of Moon    03  04:48  Moon at Ascending Node     03  11     Earth at Perihelion: 0.98334 AU    03  17     Quadrantid Meteor Shower    04  00:51  Partial Solar Eclipse; mag=0.858    04  01:03  NEW MOON     08  07     Venus at Greatest Elong: 47.0°W    09  06     Mercury at Greatest Elong: 23.3°W    09  21:38  Moon at Apogee: 404976 km    12  03:31  FIRST QUARTER MOON     15  04:39  Pleiades 1.3°N of Moon    17  16:06  Moon at Descending Node     19  13:21  FULL MOON     21  16:10  Moon at Perigee: 362793 km    21  17:55  Regulus 5.3°N of Moon    25  09:38  Spica 3.0°N of Moon    26  04:57  LAST QUARTER MOON     28  15:53  Antares 2.6°S of Moon    29  19:36  Venus 3.5°N of Moon    30  10:29  Moon at Ascending Node     31  01     Mercury at Aphelion Feb 01  10:14  Mercury 3.6°S of Moon    02  18:31  NEW MOON     04  09     Mars in Conjunction with Sun     06  15:13  Moon at Apogee: 405924 km    10  23:18  FIRST QUARTER MOON     11  13:32  Pleiades 1.4°N of Moon    14  00:14  Moon at Descending Node     17  01     Neptune in Conjunction with Sun     18  00:36  FULL MOON     18  04:18  Regulus 5.2°N of Moon    18  23:27  Moon at Perigee: 358247 km    21  17:02  Spica 2.8°N of Moon    24  15:26  LAST QUARTER MOON     24  21:26  Antares 2.8°S of Moon    25  00     Mercury at Superior Conjunction     26  12:19  Moon at Ascending Node     28  19:40  Venus 1.6°S of MoonMar 04  12:46  NEW MOON     05  23:50  Moon at Apogee: 406584 km    09  06     Mars at Perihelion:  1.38138 AU    10  20:35  Pleiades 1.7°N of Moon    12  15:45  FIRST QUARTER MOON     13  03:55  Moon at Descending Node     15  12     Mercury 2.0°N of Jupiter    16  00     Mercury at Perihelion     17  09     Jupiter at Perihelion:  4.94839 AU    17  15:35  Regulus 5.3°N of Moon    19  10:10  FULL MOON     19  11:09  Moon at Perigee: 356578 km    20  15:21  Vernal Equinox     21  03:00  Spica 2.6°N of Moon    21  04     Uranus in Conjunction with Sun     22  17     Mercury at Greatest Elong: 18.6°E    24  04:48  Antares 3.0°S of Moon    25  13:09  Moon at Ascending Node     26  04:07  LAST QUARTER MOON Apr 02  01:00  Moon at Apogee: 406656 km    03  06:32  NEW MOON     03  15     Saturn at Opposition     06  07     Jupiter in Conjunction with Sun     07  02:19  Pleiades 1.9°N of Moon    09  04:48  Moon at Descending Node     09  11     Mercury at Inferior Conjunction     11  04:05  FIRST QUARTER MOON     14  01:34  Regulus 5.5°N of Moon    16  21:59  Moon at Perigee: 358088 km    17  14:04  Spica 2.5°N of Moon    17  18:44  FULL MOON     18  16     Venus at Aphelion     19  10     Mercury 0.6°N of Mars    20  14:21  Antares 3.2°S of Moon    21  17:05  Moon at Ascending Node     22  15     Lyrid Meteor Shower    24  18:47  LAST QUARTER MOON     29  10:02  Moon at Apogee: 406043 km    30  20     Mars 0.4°N of JupiterMay 02  22:51  NEW MOON     05  04     Eta-Aquarid Meteor Shower    06  06:54  Moon at Descending Node     07  11     Mercury at Greatest Elong: 26.6°W    07  21     Mercury 1.4°S of Venus    10  12:33  FIRST QUARTER MOON     11  07     Venus 0.6°S of Jupiter    11  09:05  Regulus 5.7°N of Moon    11  12     Mercury 2.1°S of Jupiter    15  00:08  Spica 2.6°N of Moon    15  03:18  Moon at Perigee: 362133 km    17  03:09  FULL MOON     17  23     Mercury 1.4°S of Venus    18  00:46  Antares 3.3°S of Moon    19  01:03  Moon at Ascending Node     21  00     Mercury 2.1°S of Mars    23  01     Venus 1.0°S of Mars    24  10:52  LAST QUARTER MOON     27  01:58  Moon at Apogee: 405006 km    29  06:31  Jupiter 5.7°S of Moon    30  12:04  Mars 3.8°S of Moon    30  20:00  Venus 4.4°S of MoonJun 01  13:03  NEW MOON     01  13:16  Partial Solar Eclipse; mag=0.601    02  12:21  Moon at Descending Node     07  14:45  Regulus 5.7°N of Moon    08  18:11  FIRST QUARTER MOON     09  06:50  Venus 5.0°S of Pleiades    11  07:57  Spica 2.6°N of Moon    11  17:42  Moon at Perigee: 367188 km    12  00     Mercury at Perihelion     12  15     Mercury at Superior Conjunction     14  10:17  Antares 3.3°S of Moon    15  10:35  Moon at Ascending Node     15  12:13  Total Lunar Eclipse; mag=1.700    15  12:13  FULL MOON     17  04:15  Venus 4.6°N of Aldebaran    20  17:24  Mars 4.2°S of Pleiades    21  09:16  Summer Solstice     23  03:48  LAST QUARTER MOON     23  20:13  Moon at Apogee: 404275 km    26  00:45  Jupiter 5.4°S of Moon    27  22:52  Pleiades 2.0°N of Moon    27  23:40  Mercury 4.7°S of Pollux    28  10:59  Mars 1.7°S of Moon    29  20:14  Moon at Descending Node 
Date     PST   Event        (h:m)Jul 01  00:38  Partial Solar Eclipse; mag=0.097    01  00:54  NEW MOON     02  18:11  Mercury 5.1°N of Moon    04  07     Earth at Aphelion: 1.01674 AU    04  11:18  Mars 5.4°N of Aldebaran    04  20:23  Regulus 5.7°N of Moon    06  09:36  Mercury 0.2°S of Beehive    07  06:04  Moon at Perigee: 369566 km    07  22:29  FIRST QUARTER MOON     08  13:44  Spica 2.6°N of Moon    11  17:48  Antares 3.3°S of Moon    12  18:27  Moon at Ascending Node     14  22:40  FULL MOON     19  21     Mercury at Greatest Elong: 26.8°E    21  14:46  Moon at Apogee: 404358 km    22  21:02  LAST QUARTER MOON     23  16:34  Jupiter 5.1°S of Moon    25  07:28  Pleiades 2.1°N of Moon    25  23     Mercury at Aphelion     26  04:51  Mercury 2.1°S of Regulus    27  04:03  Moon at Descending Node     27  08:52  Mars 0.5°N of Moon: Occn.    28  06     Delta-Aquarid Meteor Shower    30  10:40  NEW MOON Aug 01  03:20  Mercury 1.5°N of Moon    01  03:41  Regulus 5.6°N of Moon    02  12:59  Moon at Perigee: 365756 km    04  19:08  Spica 2.4°N of Moon    06  03:08  FIRST QUARTER MOON     07  23:32  Antares 3.5°S of Moon    08  22:35  Moon at Ascending Node     09  00     Venus at Perihelion     12  22     Perseid Meteor Shower    13  10:58  FULL MOON     16  04     Venus at Superior Conjunction     16  17     Mercury at Inferior Conjunction     18  08:23  Moon at Apogee: 405161 km    20  04:13  Jupiter 4.8°S of Moon    21  13:55  LAST QUARTER MOON     21  15:40  Pleiades 2.3°N of Moon    22  14     Neptune at Opposition     23  09:23  Moon at Descending Node     25  05:36  Mars 2.7°N of Moon    27  17:07  Mercury 2.6°N of Moon    28  19:04  NEW MOON     30  09:35  Moon at Perigee: 360858 kmSep 01  02:06  Spica 2.2°N of Moon    02  22     Mercury at Greatest Elong: 18.1°W    04  05:00  Antares 3.7°S of Moon    04  09:39  FIRST QUARTER MOON     04  23:36  Moon at Ascending Node     07  23     Mercury at Perihelion     08  00:45  Mars 5.8°S of Pollux    08  18:18  Mercury 0.6°N of Regulus    12  01:27  FULL MOON     14  22:23  Moon at Apogee: 406068 km    16  10:20  Jupiter 4.7°S of Moon    17  22:46  Pleiades 2.5°N of Moon    19  11:38  Moon at Descending Node     20  05:39  LAST QUARTER MOON     23  00:23  Mars 4.8°N of Moon    23  01:05  Autumnal Equinox     24  23:49  Regulus 5.7°N of Moon    25  16     Uranus at Opposition     27  03:09  NEW MOON     27  17:01  Moon at Perigee: 357556 km    28  12     Mercury at Superior Conjunction     29  19     Venus 1.3°S of Saturn    30  16:53  Mars 0.4°S of BeehiveOct 01  12:04  Antares 3.9°S of Moon    02  01:09  Moon at Ascending Node     03  19:15  FIRST QUARTER MOON     11  18:06  FULL MOON     12  03:43  Moon at Apogee: 406435 km    13  11:28  Jupiter 4.8°S of Moon    13  13     Saturn in Conjunction with Sun     15  04:49  Pleiades 2.7°N of Moon    16  13:01  Moon at Descending Node     19  19:30  LAST QUARTER MOON     21  14     Orionid Meteor Shower    22  09:52  Regulus 5.8°N of Moon    26  04:26  Moon at Perigee: 357051 km    26  11:56  NEW MOON     27  18:14  Mercury 0.2°N of Moon: Occn.    27  21:11  Venus 1.8°N of Moon    28  17     Jupiter at Opposition     28  21:37  Antares 4.1°S of Moon    29  06:59  Moon at Ascending Node Nov 01  12     Mercury 2.0°S of Venus    02  08:38  FIRST QUARTER MOON     05  14     S Taurid Meteor Shower    08  05:20  Moon at Apogee: 406177 km    09  10:40  Jupiter 5.0°S of Moon    09  23:51  Venus 3.8°N of Antares    10  00:27  Mercury 1.9°N of Antares    10  10:21  Mars 1.3°N of Regulus    10  12:16  FULL MOON     11  03:32  Saturn 4.0°N of Spica    11  10:43  Pleiades 2.8°N of Moon    12  09:18  Aldebaran 5.9°S of Moon    12  14     N Taurid Meteor Shower    12  16:35  Moon at Descending Node     13  00     Mercury 2.0°S of Venus    14  01     Mercury at Greatest Elong: 22.7°E    17  20     Leonid Meteor Shower    18  07:09  LAST QUARTER MOON     18  17:42  Regulus 6.0°N of Moon    22  09:21  Spica 2.1°N of Moon    23  15:24  Moon at Perigee: 359692 km    24  22:10  NEW MOON     24  22:20  Partial Solar Eclipse; mag=0.905    25  17:02  Moon at Ascending Node     26  01:48  Mercury 1.7°S of Moon    26  20:29  Venus 2.8°S of MoonDec 02  01:52  FIRST QUARTER MOON     04  01     Mercury at Inferior Conjunction     04  22     Mercury at Perihelion     05  17:13  Moon at Apogee: 405414 km    06  12:10  Jupiter 5.2°S of Moon    08  17:26  Pleiades 2.8°N of Moon    09  15:51  Aldebaran 5.9°S of Moon    09  23:04  Moon at Descending Node     10  06:32  Total Lunar Eclipse; mag=1.106    10  06:36  FULL MOON     14  09     Geminid Meteor Shower    15  23:26  Regulus 6.0°N of Moon    17  16:48  LAST QUARTER MOON     19  17:37  Spica 2.1°N of Moon    21  18:56  Moon at Perigee: 364801 km    21  21:30  Winter Solstice     22  18     Ursid Meteor Shower    22  19     Mercury at Greatest Elong: 21.8°W    22  19:05  Antares 4.1°S of Moon    22  19:50  Mercury 2.6°N of Moon    23  03:36  Moon at Ascending Node     24  02:36  Mercury 6.3°N of Antares    24  10:06  NEW MOON     

 Terms Used in Astronomical Events Calendar 
  • Perihelion - instant when a planet is closest to the Sun
  • Aphelion - instant when a planet is furthest from the Sun
  • Perigee - instant when the Moon is closest to Earth
  • Apogee - instant when the Moon is furthest from Earth
  • Inferior Conjunction - instant when a planet (Mercury or Venus) passes between Earth and the Sun
  • Superior Conjunction - instant when a planet (Mercury or Venus) passes on the opposite side of the Sun from Earth 
  • Greatest Elongation - the maximum angular separation between the Sun and the planet (Mercury or Venus) 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 - instant when a planet appears opposite the Sun as seen from Earth
  • Conjunction - instant when a planet appears closest the Sun as seen from Earth
  • Occultation - the Moon occults or eclipses a star or planet
  • Ascending Node - point where the Moon crosses from the southern to northern portion of its orbit
  • Descending Node - point where the Moon crosses from the northern to the southern portion of its orbit

  • Aldebaran - bright star in the constellation Taurus
  • Pollux - bright star in the constellation Gemini
  • Regulus - bright star in the constellation Leo
  • Spica - bright star in the constellation Virgo
  • Antares - bright star in the constellation Scorpius
  • Pleiades - bright star cluster in the constellation Taurus
  • Beehive - bright star cluster in the constellation Cancer
Calendars of Astronomical Events: 2011 to 2020
The Americas
Below are links to calendars of astronomical events from 2011 to 2020 for seven time zones in the Americas. 
Choose a time zone and click on a year to get a calendar of astronomical events for that year.
   Calendars of Astronomical Events - The Americas
   AST    2011     2012     2013     2014     2015     2016     2017     2018     2019     2020 
   EST    2011     2012     2013     2014     2015     2016     2017     2018     2019     2020 
   CST    2011     2012     2013     2014     2015     2016     2017     2018     2019     2020 
   MST    2011     2012     2013     2014     2015     2016     2017     2018     2019     2020 
   PST    2011     2012     2013     2014     2015     2016     2017     2018     2019     2020 
   AKST    2011     2012     2013     2014     2015     2016     2017     2018     2019     2020 
   HST    2011     2012     2013     2014     2015     2016     2017     2018     2019     2020 
        Time Zones Abbreviations
        • AST = Atlantic Standard Time (= GMT - 4 hours)
        • EST = Eastern Standard Time (= GMT - 5 hours)
        • CST = Central Standard Time (= GMT - 6 hours)
        • MST = Mountain Standard Time (= GMT - 7 hours)
        • PST = Pacific Standard Time (= GMT - 8 hours)
        • AKST = Alaskan Standard Time (= GMT - 9 hours)
        • HST = Hawaiian Standard Time (= GMT - 10 hours)
           (where GMT = Greenwich Mean Time)
A time zone may have a different name in different countries. Note the difference in hours between a given time zone and Greenwich Mean Time to help in identification.
For other years and other time zones, visit: Calendars of Astronomical Events.
 
Accuracy of the Astronomical Events Calendars
The goal of the Astronomical Events Calendars is to present a wide range of solar system phenomena with reasonable accuracy. In general, events listed to the nearest hour are accurate to ± 30 minutes.Events listed with a precision in hours and minutes (i.e., hh:mm) are typically accurate to ± 5 minutes or less.  
The following table gives a more detailed breakdown of the accuracy of times for various astronomical events.
Accuracy of the Astronomical Events Calendars
 Solstice/Equinox (Earth)  ± 0.5 minute 
 Aphelion/Perihelion (Earth)  ± 30 minutes;  ± 0.00001 AU 
 Solar and Lunar Eclipses   ± 0.5 minute 
 Phases of the Moon  ± 0.5 minute 
 Moon at Nodes  ± 2 minutes 
 Apogee/Perigee of Moon  ± 5 minutes; ± 5 kilometers 
 Conjunctions of Moon with Star or Planet  ± 10 minutes 
 Conjunctions of Planet with Planet  ± 3 hours 
 Inferior/Superior Conjunctions (Mercury & Venus)  ± 30 minutes 
 Greatest Elongation (Mercury & Venus)  ± 30 minutes 
 Opposition/Conjunction (Outer Planets)  ± 3 hours 
 Aphelion/Perihelion of Planets  ± 30 minutes 

Acknowledgements
All calculations are by Fred Espenak and he assumes full responsibility for their accuracy. Algorithms used in predicting many of the astronomical events 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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