Astronomical Diary
fullmoonjpg lastquarterjpg newmoonjpg firstquarter.jpg
Full Moon Last Quarter New Moon First Quarter
Sep 2
1:22 PM
Sep 10
5:26 PM
Sep 17
7:00 PM
Sep 24
9:55 AM
Current Condition X-ray Solar Flares

Speed: 576.4 km/sec
Density: 8.1 protons/cm3
More Data: ACE, DSCOVR

Explanation | More Data
Updated: Sep 1 at 0005 UT

***The sun is blank--no sunspots.

Credit: Solar Dynamics Observatory(SDO)/Helioseismic
and Magnetic Imager (HMI).
Daily Sun: 31 August 2020
6-hr max: A3 1942 UT Aug31
24-hr: A5 1716 UT Aug31
Explanation | More Data
Updated: Sep 01 at 0010 UT
Time (PST) of rise and set of some planets at 10-day interval
Rise Set Rise Set Rise Set Rise Set Rise Set
Sep 07 6:55 AM 6:59 PM 2:38 AM 3:23 PM 8:29 PM *8:50 AM 2:27 PM *1:45 AM 3:01 PM *2:21 AM
Sep 17 7:17 AM 7:06 PM 2:47 AM 3:27 PM 7:48 PM *8:09 AM 1:48 PM *1:05 AM 2:20 PM *1:41 AM
Sep 27 7:30 AM 7:06 PM 2:56 AM 3:30 PM 7:02 PM *7:23 AM 1:10 PM *12:07 AM 1:41 PM *1:01 AM

* = Following day
Astronomical Events September 2020


The equinoxes are the only times when the solar terminator (the "edge" between night and day) is perpendicular to the equator. On an equinox, day and night are of approximately equal duration all over the planet. They are not exactly equal, however, due to the angular size of the sun and atmospheric refraction.

Autumnal equinox will occur on September 22 at 9:31 PM. Hence, thereafter, Philippine nights will be longer as the Sun moves below the celestial equator towards the southern hemisphere.

Figures 2 and 2a represent the position of the Earth and Sun during Solstices and Equinoxes.

Figure 2
Figure 2
Figure 2a
Figure 2a
Stars and Constellations

Stargazing during the month will give a fine display of celestial bodies such as stars and constellations after sunset and before sunrise. The famous Summer Triangle of the stars Vega, Deneb, and Altair of the constellations Lyra, Aquila, and Cygnus respectively, is well placed above the eastern horizon, as shown in Figures 1 & 1a. This month, the rich band of constellations and stars along the Milky Way from the constellations Cygnus, the Swan, in the north to Sagittarius and Scorpius in the south, begin to give way to fainter constellations, many of them with watery associations such as the constellations of Capricornus, the Sea-Goat, Aquarius, the Water Bearer, and Pisces the Fish. The famous asterism Teapot in the sky of the constellation Sagittarius can be observed at about 40 to 45 degrees above the south-southeastern horizon as also shown in the Figures.

Figure 1
Figure 1a
Planets Whereabout

On September 1 at 4:00 AM, Venus can be spotted at 20 degrees above the east northeastern horizon, shining brilliantly at magnitude -4.28. It will lie among the background stars of the constellation Gemini, the Twin during the first week, and traverses into the constellation of Cancer, the Crab up to the end of the month. The planet will remain visible in the sky before sunrise during the month of September.

At 7:00 PM, Jupiter and Saturn can be located 47 and 44 degrees above the southeastern sky, both lying among the background stars of the constellation Sagittarius, the Archer, glowing at magnitudes -2.56 and +0.31, respectively. These two planets will remain visible in the evening sky throughout the month.

At 11:00 PM, Uranus and Mars will be observed at about 21 and 30 degrees above the eastern horizon, lying among the background stars of the constellation Aries, the Ram and Pisces, the Fish, and will be glowing feebly at magnitudes of +5.72 and +1.82, respectively. Both planets will be observable throughout the month.

Mercury will be difficult to observe due to its proximity to the Sun during the month.

6 Moon at apogee (farthest distance to Earth = 405,551.141 km) 2:29 PM
10 Aldebaran 4.6° N of Moon 2:00 AM
14 Neptune opposition 3:00 AM
15 Regulus 4.3° N of Moon 12:00 AM
18 Moon at perigee (nearest distance to Earth = 359,180.800 km) 9:28 PM
22 Autumnal Equinox 9:31 PM


Regarding the publication on page 2 of the ALMANAC FOR GEODETIC ENGINEERS 2020, which contains the data for the EPHEMERIS OF THE SUN, it was verified that the February 29, 2020 date is missing but the data for the particular date is the data printed as March 1, 2020. The data printed from April 3 to December 31 are all correct.

Kindly refer to the image/link below for the data errata on the Ephemeris of the Sun 2020.
Errata of AGE 2020, page 2
(Errata of AGE 2020 pdf file)