Ephemeris: 10/28/2024 – The Pleiades or Seven Sisters and their half sisters

October 28, 2024 Comments off

This is Ephemeris for Monday, October 28th. Today the Sun will be up for 10 hours and 20 minutes, setting at 6:36, and it will rise tomorrow at 8:17. The Moon, halfway from last quarter to new, will rise at 5:22 tomorrow morning.

The beautiful star cluster of the Pleiades is seen low in the east northeastern sky after 9:00 PM. It is also known as the Seven Sisters. It has been known as a group of female stars in many cultures. Also, the Ancient Greeks, because they thought that the Pleiades shape looked something like a sail, Also, Pleiades is very close to the Greek name for sail, and that its appearance in the morning sky in early summer heralded the beginning of the summer sailing season on the Mediterranean Sea. According to Greek mythology the Pleiades have half sisters, also seven in number, with the same father, Atlas, but a different mother, called the Hyades which rises about an hour later, and fills out the face of Taurus the bull.

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

Two star clusters, the Pleiades and the Hyades in Taurus
The two star clusters the Pleiades and the Hyades, in Taurus, seen here as they would appear in the east-northeast rising in the evening. More stars are shown here than would be visible to the naked eye or in binoculars. The letter V shape of the Hyades is much more pronounced to the naked eye than it is in this photograph. The blue glow around the Pleiades is a reflection nebula because the stars are inside a cloud of dust. Other dusty areas can be seen in the photograph between these two clusters as a slight mottling of the background blackness of the sky. The bright star at the bottom of the ellipse circling the Hyades is the first magnitude star Aldebaran. It is actually not part of the physical star cluster called the Hyades, being about half the distance to it. Based on a photograph by the author.
Categories: Ephemeris Program, Observing, Star Clusters Tags: , ,

Ephemeris: 10/25/2024 – Finding the Pleiades or Seven Sisters

October 25, 2024 Comments off

This is Ephemeris for Friday, October 25th. Today the Sun will be up for 10 hours and 28 minutes, setting at 6:40, and it will rise tomorrow at 8:13. The Moon, 1 day past last quarter, will rise at 2:09 tomorrow morning.

A marvelous member of the autumn skies can be found low in the east northeast after 9 in the evening. It is the famous star cluster called the Pleiades or the Seven Sisters. I might also add the ‘Tiny Dipper’. Many people can spot a tiny dipper shape in its six or seven stars, and mistake it for the Little Dipper. With binoculars, one can see over a hundred stars that appear, along with the dipper shape of the brightest. In photographs, the Pleiades actually contain wisps of the dust they are currently passing through. In Greek mythology, the sisters were daughters of the god Atlas and Pleione. The most people can see is six stars. The reason, according to mythology, is that one of the sisters married a mortal, dimming her star.

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

A Pleiades Finder chart for about 9 PM this evening, October 25th. The Pleiades appear somewhat brighter here than it actually is in the sky. I find it a challenge to see more than about five of those seven stars. Created using Stellarium with the Pleiades label using LibreOffice Draw, and GIMP.
Named Pleiads
The named stars of the Pleiades. This is also showing more stars than can be seen with the naked eye. This is the number of stars that can be seen in binoculars, which is the best way to observe them. Most telescopes offer too much magnification to fit all the stars in. A small telescope with a thirty power magnification, wide angle eyepiece can just fit all the stars in. Created using Stellarium.
Categories: Ephemeris Program, Observing, Star Cluster Tags: ,

Ephemeris: 10/24/2024 – Looking at Comet Tsuchinshan-ATLAS for the rest of the month

October 24, 2024 Comments off

This is Ephemeris for Thursday, October 24th. Today the Sun will be up for 10 hours and 31 minutes, setting at 6:42, and it will rise tomorrow at 8:12. The Moon, at last quarter today, will rise at 1:01 tomorrow morning.

Looking at the rest of the month in viewing Comet Tsuchinshan-ATLAS in dark skies, we find it moving away from us and dimming rapidly. It will be moving across the constellation of Ophiuchus and it will be mostly in the west southwestern sky, And will need a pair of binoculars or a small telescope to spot. The comet has an easily seen tail, even when it becomes dim and only visible in binoculars. It should still have a tail. Comets sport two tails, a dust tail the bright tail that we see on comets, and a narrower ion tail. The ionized gas of the ion tail is driven back by the solar wind while the dust tail is predominantly affected by the pressure of sunlight itself. When close to the Sun it is moving more sideways, so the tails will appear to separate.

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

A finder chart for Comet Tsuchinshan-ATLAS from last night until the end of the month
A finder chart for Comet Tsuchinshan-ATLAS from last night until the end of the month. The labels for each plot is the date followed by the magnitude in parentheses. According to the latest brightness observations, it appears that the comet is a magnitude dimmer or about two and a half times dimmer. It requires at least binoculars to spot even now. Created using Stellarium.
Categories: Comet, Ephemeris Program, Observing Tags:

Ephemeris: 10/23/2024 – Taking a look at this week’s brighter solar system bodies

October 23, 2024 Comments off

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

Venus in evening twilight, approximately three quarters of an hour after sunset
Venus in evening twilight, approximately three quarters of an hour after sunset. For the Grand Traverse area of Michigan that would be about 7:30 PM tonight, October 23, 2024. Created using Stellarium.
Saturn, keeping company with Fomalhaut, the loneliest star in the sky
Saturn, keeping company with Fomalhaut, the loneliest star in the sky in the siuth-southeastern sky at 9 PM. Created using Stellarium
Jupiter low in the east-northeast at 11 PM this evening
Jupiter low in the east-northeast at 11 PM this evening. Created using Stellarium.
A finder chart for Comet Tsuchinshan-ATLAS for tonight and for the next 7 days
A finder chart for Comet Tsuchinshan-ATLAS for tonight and for the next 7 days. Created using Stellarium.
Jupiter, Mars and the Moon among the stars of winter seen at 7 AM tomorrow morning
Jupiter, Mars and the Moon among the stars of winter seen at 7 AM tomorrow morning October 24, 2024. Created using Stellarium.
The Moon three hours past last quarter at 7 AM tomorrow morning
The Moon three hours past last quarter at 7 AM tomorrow morning, October 24, 2024. Selected features are labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Telescopic Venus, Saturn and Jupiter
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. All the planets shown are for tonight, the evening of October 23, 2024. Venus and Saturn are from the evening of the 25th 2024, Apparent diameters: Venus 13.6″, 79.2% illuminated; Saturn 18.6″, its rings 43.2″, 5.1 degrees from edge on (opening up a bit); Jupiter 45.2″; Mars, too small to be represented here, is 8.7″. Saturn’s rings are actually much brighter than depicted here. The ” means seconds of arc, or 1/3600th of a degree. Created using Cartes du Ciel (Sky Charts).
A low precision ephemeris of the Sun Moon and naked eye planet positions
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, October 23 and 24, 2024. Some of the columns are self-explanatory, others 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: Comet, Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , ,

Ephemeris: 10/22/2024 – Reviewing last week’s showing of Comet Tsuchinshan-ATLAS

October 22, 2024 Comments off

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 16th comet picture

October 17th

October 17th comet picture

Comet track

This chart is from last Wednesday's planetary pos
This chart is from last Wednesday’s planetary post. Tonight’s position for the comet is marked 22 and it’s the second from the top of the posiotions of the comet. Tomorrow’s post will post the next 8 days positions for the comet. The number in parentheses next to the date is an estimated magnitude or brightness magnitude. 3 is fairly dim especially for comets so binoculars will probably be needed to find it.
Categories: Comet, Ephemeris Program, Observing Tags: ,

Ephemeris: 10/21/2024 – Comets and meteors

October 21, 2024 Comments off

This is Bob Moler with Ephemeris for Monday, October 21st. Today the Sun will be up for 10 hours and 40 minutes, setting at 6:47, and it will rise tomorrow at 8:08. The Moon, 3 days before last quarter, will rise at 9:35 this evening.

Comet Tsuchinshan-ATLAS it’s now far enough away from the sun so it stays up most of the evening, setting at 10:44 PM. It will be seen in the west southwestern sky for the most part. And now that it is dimming, it is probably best seen with binoculars. Last night was the peak of the Orionid meteor shower. The shower had to compete with a bright Moon. Meteor showers are caused by comets shedding their material as they pass close to the Sun, as the gases sublimate liberating dust and rocks. Dust and gases are blown back into the tails of a comet. The bits of rock end up in much the same orbit as the comet. If the comet’s orbit crosses the Earth’s orbit We have a meteor shower. The Orionids are caused by debris from Halley’s comet.

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

Halley's Comet Orbit and meteor showers
Halley’s Comet’s orbit with the orbits of the inner planets showing the points at which the debris from the comet intersect with the Earth’s orbit causing meteor showers. Diagram credit JPL Small-Body Database Browser with annotations.
Categories: Comet, Ephemeris Program, Meteor Shower Tags: , ,

Ephemeris: 10/18/2024 – Comet Tsuchinshan-ATLAS can barely compete with the bright Moon

October 18, 2024 Comments off

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

An animated finder chart for Comet Tsuchinshan-ATLAS for four nights from tonight the 18th through Monday night the 21st. Created using Stellarium and GIMP.
Comet Tsuchinshan-ATLAS at 9:03 PM last evening
Comet Tsuchinshan-ATLAS at 9:03 PM last evening,. photographed from my backyard. Compare it to yesterday’s photograph from on yesterday’s post . Even though the sky was clearer the comet was definitely dimmer. I could not see it with my unaided eyes . However, it did show up in binoculars, barely competing with the bright moonlit sky. Click or tap on the image to enlarge it. Created by the author.
Categories: Comet, Ephemeris Program, Observing Tags:

Ephemeris: 10/17/2024 – Comets look a lot bigger than they actually are

October 17, 2024 Comments off

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

The comet will be in this position October 17th 2024 at 8 PM
The comet will be in this position October 17th 2024 at 8 PM. Compare the comet’s position to the two pairs of stars to the comet’s left and right with the photograph below. These two pairs of stars are also visible above where the comet was last night. I found that the two pairs of stars the right and just above the comet were a good pointer to where the comet was using binoculars, scanning to the left from Arcturus. Created using Stellarium.
Photograph of C/2024 A3 (Tsuchinshan-ATLAS) at 8:47 PM EDT, October 16th 2024
Photograph of C/2024 A3 (Tsuchinshan-ATLAS) at 8:47 PM EDT, October 16th 2024 (00:47 UT, October 17, 2024). Cropped from a 4 second exposure at f/ 3.5, ISO-800, 18 mm focal length using a Canon EOS REBEL T5. Careful study of the tail suggests that it’s 8 degrees long. Credit: the author.

Categories: Comet, Ephemeris Program, Observing Tags:

Ephemeris: 10/16/2024 – Where are the naked-eye planets and the comet?

October 16, 2024 Comments off

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

An animated finder for Comet Tsuchinshan-ATLAS and Venus for tonight and for the next 7 days. Venus is in the lower left on the horizon for tonight. The image contains 3 frames the first is tonight at 8 PM without any annotations. The second adds names and constellation outlines. The third is the comet’s position for tonight in the next 7 days. Created using Stellarium and GIMP.
Saturn and the Moon tonight at 8:00 PM along with the star Fomalhaut just rising . Created using Stellarium
Jupiter low in the east northeast at 11 PM this evening. Created using Stellarium.
Jupiter and Mars among the stars of winter seen at 7 AM tomorrow morning. Created using Stellarium.
Telescopic Venus, Saturn and Jupiter (north up) as they would be seen in a small telescope with the same magnification. Venus and Saturn are from 8 pm, and Jupiter for 11 pm tonight, October 16, 2024. Apparent diameters: Venus 13.2″, 81.0% illuminated; Saturn 18.7″, its rings 43.6″, 5.0 degrees from edge on (opening up a bit); Jupiter 44.4″; Mars, too small to be represented here, is 8.3″. The ” means seconds of arc, or 1/3600th of a degree. Click or tap on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on October16, 2024. The night ends on the left with sunrise on the 17th. Click or tap on the image to enlarge it. Created using my LookingUp app and GIMP.
This is a low precision ephemeris of the Sun Moon and naked eye planet positions for today and tomorrow, October 16 and 17, 2024. Some of the columns are self-explanatory, others 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: Comet, Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , , , ,

Ephemeris: 10/15/2024 – Comet Tsuchinshan-ATLAS should be visible this week if clouds allow

October 15, 2024 Comments off

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

This is the track of Comet Tsuchinshan-ATLAS that I posted a few days ago. Tonight’s position will be marked by 15 for the 15th of the month. The number in parentheses is a projected magnitude, which may or may not be correct. Tomorrow I will be publishing the path of the comet for the next 8 days from the 16th through the 23rd. This is the position for around 8 PM. This image was created using Stellarium.

What we’ve missed

An image of the comet taken on October 13th 2024 by Michael Jaeger from Martinsberg, Austria
This is an image of the comet taken on October 13th 2024 by Michael Jaeger from Martinsberg, Austria. This image was found on the spaceweather.com page for October 15th 2024.

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.

Categories: Comet, Ephemeris Program, Observing Tags: ,