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Ephemeris: 10/23/2024 – Taking a look at this week’s brighter solar system bodies
This is Ephemeris for Wednesday, October 23rd. Today the Sun will be up for 10 hours and 34 minutes, setting at 6:44, and it will rise tomorrow at 8:10. The Moon, 1 day before last quarter, will rise at 11:50 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be spotted in the West southwest low on the horizon at 7:15 PM, 29 minutes after sunset. It will set at 8:17. Comet Tsuchinshan-ATLAS will be west after 8:30 PM the end of astronomical twilight. It will set at 10:55 PM. Saturn will be in the southeast at 8 PM. Jupiter will rise at 9:11 PM this evening in the east northeast, and be a good object for the small telescope about an hour later. By 7:00 AM tomorrow Jupiter will be high in the southwest while Mars will be high in the south to the right of the Moon.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 10/22/2024 – Reviewing last week’s showing of Comet Tsuchinshan-ATLAS
This is Ephemeris for Tuesday, October 22nd. Today the Sun will be up for 10 hours and 37 minutes, setting at 6:45, and it will rise tomorrow at 8:09. The Moon, 2 days before last quarter, will rise at 10:40 this evening.
Comet Tsuchinshan-ATLAS continues to head out away from the Sun and the Earth, heading back to the Oort Cloud from whence it came. It’s best showing for us came last week. Unfortunately, it was cloudy the weekend before and the first part of the week when the comet was its brightest. However, by Wednesday evening I was able to spot the comet, but not with the naked eye. I could see it in binoculars and I photographed it. Between the twilight and bright moonlight my poor eyes were not able to spot it. Now that the Moon is leaving the evening sky, and the comet is moving up above the horizon in the west, it should be easily spotted with binoculars towards 9 pm. It has faded significantly and will continue as it speeds away from us.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Wednesday, October 16th
October 17th
Comet track
Ephemeris: 10/18/2024 – Comet Tsuchinshan-ATLAS can barely compete with the bright Moon
This is Ephemeris for Friday, October 18th. Today the Sun will be up for 10 hours and 49 minutes, setting at 6:52, and it will rise tomorrow at 8:04. The Moon, 1 day past full, will rise at 7:21 this evening.
Comet Tsuchinshan-ATLAS will be visible by 8:00 PM in the west-southwest. It’s a bit higher than it was last night and tomorrow night it’ll be a bit higher still. It also is fading and must also compete with the bright moonlight. It is the brightest comet that we’ve seen around here this century. We’ve been looking forward to this comet for more than a year and a half, since it’s discovery in January of last year. Comets were not always objects to look forward to. In ancient times when they suddenly appeared, they struck fear. They were thought to portend disasters. In fact the word disaster means ill-starred. The word comet basically comes from the Latin meaning hairy star. The Chinese had a similar name for them, they called them broom stars.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 10/17/2024 – Comets look a lot bigger than they actually are
This is Bob Moler with Ephemeris for Thursday, October 17th. Today the Sun will be up for 10 hours and 52 minutes, setting at 6:53, and it will rise tomorrow at 8:02. The Moon, at full today, will rise at 6:53 this evening. | Comet Tsuchinshan-ATLAS will have its greatest competition with the Moon tonight since it’s full. However, in succeeding nights the Moon will get dimmer and also rise later. At 8 PM the comet will be nearly 18° above the west-southwestern horizon with its tail pointing to up into the bit to the left.* What makes comets spectacular is that they contain volatile materials, like frozen gases, water, and carbon compounds. The solid body of the comet, called the nucleus is quite small, from less than a mile to up to 25 miles in diameter, which on the solar system scale is tiny. They live quite happily in the outer solar system where it’s cold. When approaching the Sun the gases sublimate liberating the included dust, producing the tails the comets are famous for.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
* I was able to spot the comet last night at around 8:10 PM but only through binoculars. It was not visible to my unaided eye. However, it was visible in binoculars. It also photographed well with the image showing a lot more than what was visible even through binoculars and the amount of clouds that were actually in the sky. However, the clouds were light and generally did not hinder the comet too much. The photograph of the comet below has been processed to increase its brightness and contrast with the sky.
Addendum
Ephemeris: 10/16/2024 – Where are the naked-eye planets and the comet?
This is Bob Moler with Ephemeris for Wednesday, October 16th. Today the Sun will be up for 10 hours and 55 minutes, setting at 6:55, and it will rise tomorrow at 8:01. The Moon, 1 day before full, will set at 8:11 tomorrow morning.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be spotted in the West southwest low on the horizon at 7:30 PM, 35 minutes after sunset. It will set at 8:19. Comet Tsuchinshan-ATLAS will be west southwest way above and to the right of Venus. It will set at 9:46 PM. Saturn will be in the southeast at 8 PM. Jupiter will rise at 9:40 PM this evening and be a good object for the small telescope about an hour later. Jupiter and Mars are both mourning planets so they can be seen early in the morning before sunrise. By 7:00 AM tomorrow Jupiter will be high in the southwest while Mars will be high in the South.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 10/15/2024 – Comet Tsuchinshan-ATLAS should be visible this week if clouds allow
This is Bob Moler with Ephemeris for Tuesday, October 15th. Today the Sun will be up for 10 hours and 58 minutes, setting at 6:57, and it will rise tomorrow at 8:00. The Moon, 2 days before full, will set at 6:47 tomorrow morning.
Comet Tsuchinshan-ATLAS has been visible in our evening skies for the last three nights and will be at least bright enough to be seen with the naked eye. And it should be so for most of the rest of the month. However, this week so far has been cloudy, and it will be cloudy until possibly Wednesday night however Thursday and Friday look like the best for viewing of the comet. Of course this is Michigan, so don’t hold me to it. The comet has been pretty much living up to expectations as far as its brightness and the length of its tail. The comet peak brightness which came early last week, when it could only be seen during the daytime, was as bright as the planet Venus. Now that it is headed away from the Sun and the Earth it will rapidly fade.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
What we’ve missed
It was partly cloudy on the evening of 14th, last night. I went out a little after 8 PM to see if I could spot the comet. I could see Arcturus, however I could not spot the comet or the planet Venus. However, I believe someone in our area could have spotted the comet, if they were in the right location.
Ephemeris: 10/11/2024 – Comet Tsuchinshan-ATLAS may be visible as early as tonight
This is Ephemeris for Friday, October 11th. Today the Sun will be up for 11 hours and 10 minutes, setting at 7:04, and it will rise tomorrow at 7:55. The Moon, 1 day past first quarter, will set at 1:22 tomorrow morning.
While I think the first time the spot Comet Tsuchinshan-ATLAS will be tomorrow night, sharp-eyed observers with binoculars might be able to find the comet tonight just about due west near the horizon after 7:30 PM it will be a difficult task being so close to the sun The comet will set at 8:09 PM, however if the tail is bright enough it may still be visible. The comet’s tail should be relatively short since it’s actually pointing back towards us. That may also make the tail somewhat brighter since we’re looking down through the thicker part of the tail rather than through its side. I’ve seen a lot of comets in my time, the first ones in 1957. There were two bright comets that year.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 10/09/2024 – Where are the naked-eye planets this week?
This is Ephemeris for Wednesday, October 9th. Today the Sun will be up for 11 hours and 16 minutes, setting at 7:07, and it will rise tomorrow at 7:52. The Moon, 1 day before first quarter, will set at 10:57 this evening.
Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus might be spotted in the West southwest only 7° above the horizon at 8 PM, 55 minutes after sunset. It will set at 8:23. Saturn will be in the southeast at that time. Saturn may look disappointing in telescopes this year since its rings are nearly edge on and appearing as a line through the planet like it’s stapled onto the sky. Jupiter and Mars will be up in the morning sky, with Jupiter rising about 10:08 PM in the east-northeast. By 7 AM tomorrow, Jupiter will be brighter than any of the winter stars high in the south. Mars, with its reddish hue, will be to the left of Jupiter. Comet Tsuchinshan-ATLAS will be in the western evening sky starting this weekend. It is expected to be quite bright, I’m betting with a broad tail.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 10/08/2024 – Comet Tsuchinshan-ATLAS may be brighter than expected
This is Ephemeris for Tuesday, October 8th. Today the Sun will be up for 11 hours and 19 minutes, setting at 7:09, and it will rise tomorrow at 7:51. The Moon, 2 days before first quarter, will set at 10:00 this evening.
You are going to hear a lot about a bright comet visible in the evening starting this weekend. The comet with a long name Tsuchinshan-ATLAS will begin to be visible in the evening sky, and it will be very bright. It will be the brightest comet we’ve had in some time visible in the Northern Hemisphere since Comet Hale-Bopp in 1997. The reason for this comet’s great brightness is that the comet is passing between the Earth and the Sun. This comet is very dusty with an extensive dust tail. Since the comet is passing between the Earth and Sun the dust scatters sunlight in a forward direction like seeing sunbeams through holes in the clouds near sunset. This is making the comet brighter than originally predicted.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
Ephemeris: 10/07/2024 – Comet Tsuchinshan-ATLAS will be visible starting Saturday Night
This is Ephemeris for Monday, October 7th. Today the Sun will be up for 11 hours and 22 minutes, setting at 7:11, and it will rise tomorrow at 7:50. The Moon, 3 days before first quarter, will set at 9:15 this evening.
In January of last year a Chinese observatory discovered a comet which was subsequently lost. A month and a half later another observatory in South Africa rediscovered it. That’s why the comet is named, Tsuchinshan-ATLAS after the two observatories. It was soon learned that the comet had a chance of becoming visible to the unaided eye in late September and October 2024, this month. Despite having a dimming episode earlier this year the comet promises to be naked eye and possibly even spectacular. The comet is moving from the south to the north and in a direction counter to the orbiting planets around the Sun. We will begin to see it low in the West after sunset starting Saturday.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). Times will be different for other locations.
Addendum
The comet will pass almost directly between the Earth and the Sun on the evening of the 9th. It’ll be about halfway between the Earth and the Sun at that point. It should be picked up by the Solar and Heliospheric Observatory satellite (SOHO) which is orbiting the Earth-Sun L1 Lagrange point a million miles sunward from the Earth with its C3 coronagraph*. Then the comet’s tail should be pointing almost directly at the Earth. As the comet swings out away from the Sun it will also be more rapidly moving away from Earth. This is because the comet has an orbit that is counter to that of the orbits of the Earth and the rest of the planets around the Sun and will rapidly fade as it increases its distance.
A note on the discovery designation: C/2023 A3 is C for comet; 2023, the year of discovery; A3, third object reportedly discovered in the first half of January.
The SOHO Real-time GIF Movies webpage is: https://soho.nascom.nasa.gov/data/realtime/gif/. Select LASCO/C3. It provides a time-lapse image of the Sun’s corona taken at hourly intervals for about the last 4 days.
Bob Moler's Ephemeris Blog 