2011Calendar of Astronomical Events

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

Return to: Calendars of Astronomical Events
Return to: Planetary Ephemeris Data