National Astronomical Observatory of Japan

Overview and Calendar for 2016


The most noteworthy astronomical phenomenon of 2016 is the partial eclipse of the Sun on March 9. It can be observed from throughout all of Japan, but the farther south an area is, the greater the extent of the eclipse will appear. As seen from Tokyo, the Sun will be partially eclipsed for about 2 hours, from 10:12 to 12:05. At 11:08, the time of greatest eclipse, over 15% of the solar disk will be concealed by the Moon.

Among the 3 biggest meteor showers, the timing of the peak and the phase of the Moon are favorable for the Perseid Meteor Shower, so we can expect to see many meteors. The timing of the peak of the Quadrantid Meteor Shower (January) is not good, making it ill-suited for observation. Likewise, the Geminid Meteor Shower (December) is not favorable for observation, because the Moon is bright.

Mars makes its closest approach to Earth on May 31. Earth and Mars make a close approach about every two years, but this time is the closest they have come since 2005. Because Mars appears large at the time of closest approach, this is a good chance to observe it. At that time, Mars is visible throughout the entire night. The 1st magnitude star Antares in the constellation Scorpio and Saturn are also visible nearby.

2016 is yet another year with many fun astronomical phenomena.


1New Year’s Day [Shogatsu] (national holiday)
2 Last Quarter Moon
3Earth passes perihelion
4Peak of the Quadrantid Meteor Shower (about 15 per hour)
5Mercury at stationary point
9Jupiter at stationary point
10New Moon
11Coming-of-Age Day [Seijin-no-hi] (national holiday)
14Mercury at inferior conjunction
17First Quarter Moon
24Full Moon
26Mercury at stationary point

Astronomical information for January


1Last Quarter Moon
7Greatest Western Elongation of Mercury
8New Moon
11National Foundation Day [Kenkoku-Kinen-no-hi] (national holiday)
15First Quarter Moon
23Full Moon
29Neptune at conjunction

Astronomical information for February


2Last Quarter Moon
8Jupiter at opposition
9Total solar eclipse (A partial solar eclipse can be seen from all of Japan) Reference: Solar eclipse visibility forecast for various locations / New Moon
16First Quarter Moon
20Vernal Equinox Day [Shunbun-no-hi] (national holiday) / Vernal equinox (Sun’s ecliptic longitude 0°)
23Full Moon
24Mercury at superior conjunction
25Saturn at stationary point

Astronomical information for March


1Last Quarter Moon
7New Moon
10Uranus at conjunction
14First Quarter Moon
17Mars at stationary point
18Greatest Eastern Elongation of Mercury
22Full Moon/ Peak of April Lyrid Meteor Shower (about 2 per hour)
29Mercury at stationary point/ Showa Day [Showa-no-hi] (national holiday)
30Last Quarter Moon

Astronomical information for April


3Constitution Memorial Day [Kenpou-Kinen-bi] (national holiday)
4Greenery Day [Midori-no-hi] (national holiday)
5Children’s Day [Kodomo-no-hi] (national holiday)
6Peak of Eta Aquarid Meteor Shower (about 5 per hour)
7New Moon
9Transit of Mercury across the Solar Disk (not visible from Japan) Reference: Transit visibility forecast for various locations
10Mercury at inferior conjunction/ Jupiter at stationary point
14First Quarter Moon
22Full Moon/ Mercury at stationary point/ Mars at opposition
29Last Quarter Moon
31Mars makes its closest approach to Earth (Distance 0.503 au)

Astronomical information for May


3Saturn at opposition
5New Moon/ Greatest Western Elongation of Mercury
7Venus at inferior conjunction
12First Quarter Moon
14Neptune at stationary point
20Full Moon
21Summer solstice (Sun’s ecliptic longitude 90°)
28Last Quarter Moon
30Mars at stationary point

Astronomical information for June


4New Moon
5Earth passes aphelion
7Mercury at superior conjunction
12First Quarter Moon
18Ocean Day [Umi-no-hi](national holiday)
20Full Moon
27Last Quarter Moon
30Uranus at stationary point/ Peak of Delta Aquarid Meteor Shower (about 3 per hour)

Astronomical information for July


3New Moon
9Traditional tanabata (traditional star festival)
11First Quarter Moon/ Mountain Day [Yama-no-hi](national holiday)
12Peak of Perseid Meteor Shower (about 45 per hour)
14Saturn at stationary point
17Greatest Eastern Elongation of Mercury
18Full Moon
25Last Quarter Moon
30Mercury at stationary point

Astronomical information for August


1Annular solar eclipse (not visible from Japan) Reference: Solar Eclipse visibility forecast for various locations/ New Moon
3Neptune at opposition
9First Quarter Moon
13Mercury at inferior conjunction
15Harvest Moon
17Full Moon
19Respect-for-the-Aged Day [Keiro-no-hi ](national holiday)
21Mercury at stationary point
22Autumnal Equinox Day / Autumn equinox (Sun’s ecliptic longitude 180°)
23Last Quarter Moon
26Jupiter at conjunction
29Greatest Western Elongation of Mercury

Astronomical information for September


1New Moon
8 Peak of the October Draconid Meteor Shower (about 1 per hour)
9First Quarter Moon
10Health-Sports Day [Taiku-no-hi]/ Peak of Southern Taurid Meteor Shower (about 2 per hour)
15Uranus at opposition
16Full Moon
21Peak of Orionid Meteor Shower (about 3 per hour)
23Last Quarter Moon
28Mercury at superior conjunction
31New Moon

Astronomical information for October


3Culture Day [Bunka-no-hi](national holiday)
8First Quarter Moon
12Peak of Northern Taurid Meteor Shower (about 2 per hour)
14Full Moon
16Occultation of Aldebaran (for Tokyo disappearance is at 2:23 am and reappearance is at 3:27 am)
17Peak of Leonid Meteor Shower (about 2 per hour)
20Neptune at Stationary Point
21Last Quarter Moon
23Labor Thanksgiving Day [Kinro-kansha-no-hi] (national holiday)
29New Moon

Astronomical information for November


7First Quarter Moon
10Saturn at conjunction
11Greatest Eastern Elongation of Mercury
14Full Moon/ Peak of Geminid Meteor Shower (about 10 per hour)
19Mercury at stationary point
21Last Quarter Moon/ Winter solstice (Sun’s ecliptic longitude 270°)
23Emperor’s Birthday [Tennou-Tanjyobi] (national holiday)
29New Moon/ Mercury at inferior conjunction
30Uranus at stationary point

Astronomical information for December

The days for the peak activities of the meteor showers are based on the predictions of IMO (the International Meteor Organization).