2011Calendar of Astronomical Events

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