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Archive for October, 2025

Ephemeris: 10/03/2025 – Astronomy Society meeting tonight

October 3, 2025 Comments off

This is Bob Moler with Ephemeris for Friday, October 3rd. Today the Sun will be up for 11 hours and 35 minutes, setting at 7:19, and it will rise tomorrow at 7:44. The Moon, 3 days before full, will set at 4:26 tomorrow morning.

The Grand Traverse Astronomical Society will host its October meeting tonight at 8 PM at Northwestern Michigan College’s Joseph H Rogers Observatory. I’m also in the dark as to the program. It’s always interesting, even if there is no formal program. Discussions among members with expertise in a variety of interests. Astronomy is the science of everything. After all, the Earth is a planet too. After the meeting, around 9 PM, weather permitting, there will be viewing of the Moon and whatever we can find in the twilight. The observatory is located south of Traverse City on Birmley Rd. The meeting will also be available via Zoom. Instructions will be on the society’s website, gtastro.org.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Joseph H. Rogers Observatory of Northwestern Michigan College
Joseph H. Rogers Observatory of Northwestern Michigan College, meeting place of the Grand Traverse Astronomical Society, Traverse City, Michigan.
Categories: Ephemeris Program, GTAS Outreach Event

Ephemeris: 10/02/2025 – The Artemis 2 mission may launch early next year

October 2, 2025 Comments off

This is Bob Moler with Ephemeris for Thursday, October 2nd. Today the Sun will be up for 11 hours and 38 minutes, setting at 7:20, and it will rise tomorrow at 7:43. The Moon, 3 days past first quarter, will set at 3:10 tomorrow morning.

The Artemis 2 mission to send the crew around the moon and back is slated for early next year, which surprised me a bit because the launch window was moved up to earlier next year to between February 5th and April 26 about 2 1/2 months. That doesn’t mean that the mission could slip to later in the year, recalling the delays of the Artemis 1 mission. This mission is to send four people in the Orion capsule around the moon. It is crewed by three Americans and a Canadian, three men and a woman, three whites and a black. They’re the same four astronauts. I’m sure the current administration would have screamed DEI, if it wasn’t too late to break up the crew.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

This is the planned Artemis 2 flight trajectory.
This is the planned Artemis 2 flight trajectory. Unlike Apollo 8, that dropped into close orbit of the Moon, Artemis 2 will just swing around the Moon and come back to the Earth, like Apollo 13 had to after their accident. This type of orbit is called a free return trajectory. There still needs small tweaks, called mid-course corrections, to ensure that the Orion Capsule enters the Earth’s atmosphere at the correct angle to ensure spacecraft and crew survival. Click or Tap on the image to enlarge it. Credit: NASA.

Categories: Ephemeris Program, NASA, Space exploration Tags:

Ephemeris: 10/01/2025 – Our weekly look at the whereabouts of the naked-eye planets

October 1, 2025 Comments off

This is Ephemeris for Wednesday, October 1st. Today the Sun will be up for 11 hours and 41 minutes, setting at 7:22, and it will rise tomorrow at 7:42. The Moon, 2 days past first quarter, will set at 1:55 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Saturn rises before sunset in the east. It is the brightest star like object in the eastern to southeastern sky in the evening. In a telescope Saturn sports a very thin ring, 1.5° from being edge on. Saturn has an axial tilt of about 27°, so it has seasons like the Earth and since its rings are over its equator, when they go edge on to the Sun, it is an equinox for it, which happened this past May. Earth, being close to the Sun, sees nearly the same thing. Now the ring angle for us will decrease to about a third of a degree by November 23rd before increasing. By 7 AM, Jupiter will appear high in the southeast, under the stars of Gemini. With brighter Venus low in the east.

The astronomical event times given in this blog are for the Traverse City/Interlochen area of Michigan (Lat 44.7° N, Long 85.7° W; EDT, UT – 4 hours) unless stated otherwise. Times will be different for other locations.

Addendum

Saturn in the east southeast at 9 PM tonight
Saturn in the east southeast at 9 PM tonight, October 1, 2025. Created using Stellarium.
The Moon tonight, October 1, 2025. A view visible in small telescopes showing an image with and without selected features labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Venus and Jupiter are visible in the southeastern sky among the winter stars at 7 AM tomorrow morning.
Venus and Jupiter are visible in the southeastern sky among the winter stars at 7 AM tomorrow morning, October 2, 2025. Created using Stellarium.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification.
Telescopic Saturn, Jupiter and Venus (north up) as they would be seen in a small telescope with the same magnification. On the evening of the October 1, 2025, Saturn will be 19.4″ in diameter, but its rings, being nearly edge on, should show up brighter than seen here, and extend to 45.2″. They are tilted 1.4° from being edge on. At 7 AM on the morning of October 2, 2025, Jupiter will be 37.1″ in diameter. Europa and Ganymede will be eclipsed by Jupiter then. Venus’ apparent diameter will be 11.0″, and be 91.4% illuminated. It’s on the far side of the Sun. The (”) symbol means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw and GIMP.
The naked-eye planets and the Moon at sunset and sunrise on a single night.
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on October 1st, 2025. The night ends on the left with sunrise on the 2nd. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
A low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, October 1st and 2nd, 2025. Some of the columns are self-explanatory, others are not. The transit column is the time that the body crosses the meridian and is due south. Elong, for elongation, is the angle between the Sun and that body. RA is right ascension, which is the object’s east-west position on the celestial sphere in hours and minutes. Dec is declination which is the north-south position of the object on the celestial sphere in degrees and minutes. R is the distance of that object from the Sun in astronomical units. An astronomical unit is about 93 million miles or 150 million kilometers. And Delta is the distance of that object from the Earth, also in astronomical units. I omit the ‘m’ in am and pm for compactness. The data was generated using my LookingUp for DOS app and displayed as a table by my Ephemeris Helper app.
Categories: Ephemeris Program, Naked-eye planets, Observing Tags: , , , , ,