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Archive for November, 2024

Ephemeris: 11/14/2024 – SpaceX to deorbit the International Space Station

November 14, 2024 Comments off

This is Ephemeris for Thursday, November 14th. Today the Sun will be up for 9 hours and 35 minutes, setting at 5:15, and it will rise tomorrow at 7:40. The Moon, 1 day before full, will set at 7:28 tomorrow morning.

SpaceX has received a contract from NASA to deorbit the International Space Station around the year 2030. The contract is for a little bit less than a billion dollars. SpaceX will develop a special Dragon capsule with enough fuel to deorbit the space station. The idea is to drop the space station’s orbit over a period of months and guided in its final journey to a spot in the South Pacific Ocean called Point Nemo, which is the spot between New Zealand and Chile near longitude 120° W and latitude 50° South. Point Nemo is named after the captain of the fictional submarine Nautilus from the Jules Verne novel 20,000 Leagues Under the Sea. Point Nemo is the farthest point in the South Pacific Ocean from any landmass: island or continent.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

What the special SpaceX Cargo Capsule and Trunk might look like
Image of what the special SpaceX Cargo Capsule and Trunk might look like as it deorbits the International Space Station. Credit: SpaceX.
Categories: Ephemeris Program, NASA Tags: , ,

Ephemeris: 11/13/2024 – Looking for the naked-eye planets this week

November 13, 2024 Comments off

This is Ephemeris for Wednesday, November 13th. Today the Sun will be up for 9 hours and 38 minutes, setting at 5:16, and it will rise tomorrow at 7:39. The Moon, 2 days before full, will set at 6:03 tomorrow morning.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus can be spotted low in the southwestern sky by 6 PM, about 45 minutes after sunset. It will set at 7:30. Saturn will be in the south-southeast at 7 PM. Jupiter will rise at 6:42 PM in the east northeast, and be a good object for the small telescope about an hour later. By 6:00 AM tomorrow Jupiter will be high in the west, above and right of Orion, while reddish Mars, which rises tonight near 9:56, will be high in the south-southwest. Jupiter and Saturn are good planets to view with a small telescope, while Venus and Mars will appear very small and featureless. These last two will improve next year when they move closer to us.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

Venus as it might appear tonight at 6 PM, about 45 minutes after sunset, low in the southwest. Venus is now as far South in the sky as it will get and will now begin to move northward. From now until the end of the year it will rise higher and higher in the sky in the evening. Its greatest eastern separation, or elongation, from the Sun will occur on January 2nd. Created using Stellarium.
Saturn, the Moon with Jupiter rising at 7 PM. Off to the right beyond the image, Venus setting in the southwest. Click or tap on the image to enlarge it. Created using Stellarium.
The Moon as it might appear through a small telescope tonight, November 13, 2024. Selected features are labeled. Created using stellarium, LibreOffice draw, and GIMP.
Jupiter and Mars among the stars of winter seen in the southwestern sky at 6 AM, or about an hour and a half before sunrise, tomorrow morning November 14, 2024. Created using Stellarium.
Telescopic Venus, Saturn, Jupiter and Mars (north up) as they would be seen in a small telescope with the same magnification. All the planets except Mars are shown for tonight, November 13, 2024, Mars for tomorrow morning the 14th. Apparent diameters: Venus 15.3″, 73.3% illuminated; Saturn 18.0″, its rings 41.9″, 5.3 degrees from edge on (starting to close again); Jupiter 47.4″; Mars, 10.2″, 90.1% illuminated. Saturn’s rings are actually much brighter than depicted here. Plan etary surface detail is more subtle than shown here. 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 November 13, 2024. The night ends on the left with sunrise on the 14th. 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, November 13 and 14, 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: Ephemeris Program, Naked-eye planets, Observing, Planets

Ephemeris: 11/12/2024 – SpaceX uses Cargo Dragon to change orbit of the ISS

November 12, 2024 Comments off

This is Bob Moler with Ephemeris for Tuesday, November 12th. Today the Sun will be up for 9 hours and 40 minutes, setting at 5:17, and it will rise tomorrow at 7:37. The Moon, halfway from first quarter to full, will set at 4:39 tomorrow morning.

After the last SpaceX cargo mission arrived at the International Space Station, they used the thrusters on the SpaceX capsule to raise the orbital space station a little bit as a test. SpaceX capsules dock at the forward end of the space station according to direction of travel so in order to boost the station’s orbit they had to flip the station around so that the docking port was at the rear before they could apply the needed thrust. When thrust is applied to an object in orbit the effect of the change occurs mostly at the opposite side of the orbit. In order to permanently raise or lower an object’s circular orbit one must make 2 adjustments 180° away from each other. This is the essence of the Hohmann Transfer Orbit, proposed by German scientist Walter Hohmann in 1925.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations

Addendum

Hohmann Transfer Orbit
Hohmann Transfer Orbit (2) moving, in this case. from one circular orbit (1) to a higher one (3). Moving from point a to point b. The triangle symbol is the Greek capital letter delta, which means change. It reads as delta V, or change in velocity. Image credit: Leafnode based on image by Hubert Bartkowiak in Wikimedia Commons with a and b points added by this author.

Categories: Concepts, Ephemeris Program Tags: , , ,

Ephemeris: 11/11/2024 – Still waiting for the promised nova

November 11, 2024 Comments off

This is Ephemeris for Veterans Day, Monday, November 11th. Today the Sun will be up for 9 hours and 43 minutes, setting at 5:18, and it will rise tomorrow at 7:36. The Moon, 2 days past first quarter, will set at 3:19 tomorrow morning.

We’ve been waiting all year so far for the appearance of a nova or Blaze Star, as they called it, in the constellation of Corona Borealis. The astronomical name For it is T Coronae Borealis or T CrB for short. It last erupted in 1946 and the time before that it was 1866 an interval of 80 years. This year would be 78 years since 1946 so we could be waiting another two years. Observations of the star, which is still visible, though faint, between eruptions, were not as comprehensive in the prior 80 years, as they are today. It’s possible that observations of pre-nova activity were missed during war years preceding the 1946 outburst.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

A Finder for the location of the nova, or Blaze Star, T Coronae Borealis or T CrB (when it happens), for the early evening now
A Finder for the location of the nova, or Blaze Star, T Coronae Borealis or T CrB (when it happens), for the early evening now. Corona Borealis is a small horseshoe shaped constellation whose brightest star Alphecca is just above the “n” in Corona. It is a second magnitude star about the same brightness as the nova will get at its peak. After late November the best time to see the nova, if it occurs then, will be in the morning sky just before sunrise. Though the nova is not circumpolar, meaning it rises and sets, it is up in the sky for 16 of the 24 hours of the day, so we will never completely lose it to daylight. When the Nova explosion occurs it will be visible to the naked eye for about a week so it’s easy to miss in time and also, in Northern Michigan due to the winter weather, we could miss it because of clouds. But as I mentioned in the program script above we are currently about two years away from the nominal time between between explosions, so we still have a couple of years to go before 80 years are up. Created using Stellarium, and LibreOffice Draw.
Categories: Ephemeris Program, Nova, Observing Tags: ,

Ephemeris: 11/08/2024 – The Jade Rabbit on the Moon

November 8, 2024 Comments off

This is Bob Moler with Ephemeris for Friday, November 8th. Today the Sun will be up for 9 hours and 50 minutes, setting at 5:21, and it will rise tomorrow at 7:32. The Moon, 1 day before first quarter, will set at 11:24 this evening.

Tonight’s Moon is just a few hours before the instant of first quarter which is officially at 12:56 tomorrow morning. The ancient Chinese saw in the gray areas of the Moon, we call seas, a rabbit, a pet of Chinese moon goddess Chang’e, its name was Yutu. These have become the names of the Chinese lunar landers and rovers. The top half of that rabbit is visible in the gray areas called maria, or seas. Early telescopic astronomers thought they were actually water filled basins. It turned out to be lava plains, actually floors of huge craters, from asteroids that hit the Moon 4 billion years ago during the late heavy bombardment. The top body of the rabbit is at the top part of the moon it descends to the lower right with his head and ears. The rabbit is also known as the Jade Rabbit. The rest of him is visible when the moon is full. Yutu has a real presence on the Moon, as the names of the two Chinese rovers that landed on the Moon.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

The top part of the Jade Rabbit, as I imagine it upside down, superimposed on tonight's nearly first quarter Moon
The top part of the Jade Rabbit, as I imagine it upside down, superimposed on tonight’s nearly first quarter Moon. Created using Stellarium, LibreOffice Draw, and GIMP.

Categories: China, Ephemeris Program, Observing, The Moon Tags: , , ,

Ephemeris: 11/07/2024 – The Moon wobbles from Earth’s point of view

November 7, 2024 Comments off

This is Ephemeris for Thursday, November 7th. Today the Sun will be up for 9 hours and 53 minutes, setting at 5:22, and it will rise tomorrow at 7:31. The Moon, 2 days before first quarter, will set at 10:08 this evening.

The nearly seven day old Moon appears very low in the southwestern sky tonight. It appears as a fat crescent. The small sea called Mare Crisium or Sea of Crises, near the west edge of the Moon is a good indicator of what we call libration, that is the Moon’s slow wobbling back and forth over the month as it orbits the Earth. One can judge the amount of libration by the distance of that small round sea from the edge of the Moon. This happens because the Moon’s rotation is steady while its orbital velocity around the Earth is not, because its orbit is slightly elliptical. So sometimes the rotation gets ahead of its revolution about the Earth, and sometimes it’s behind. Right now that libration is pushing that small sea towards the edge of the Moon.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

Moon's libration animation
Simulation of the Moon’s distance, phase and libration for October 2007 by Tomruen. Image is in the Public Domain.
Categories: Concepts, Ephemeris Program, Observing, The Moon Tags:

Ephemeris: 11/06/2024 – Where are the naked eye planets this week?

November 6, 2024 Comments off

This is Ephemeris for Wednesday, November 6th. Today the Sun will be up for 9 hours and 55 minutes, setting at 5:24, and it will rise tomorrow at 7:29. The Moon, 3 days before first quarter, will set at 8:56 this evening.

Let’s take our weekly look at the whereabouts of the naked-eye planets. Venus can be spotted low in the southwestern sky by 6 PM, about half an hour after sunset. It will set at 7:22. Saturn will be in the southeast at 7 PM. Jupiter will rise at 7:17 PM in the east northeast, and be a good object for the small telescope about an hour later. By 6:00 AM tomorrow Jupiter will be high in the west southwest, among the winter stars, while reddish Mars, which rises tonight near 10:16, will be high in the south. Jupiter and Saturn are good planets to view with a small telescope, while Venus and Mars will appear very small and featureless. These last two will improve next year when they move closer to us.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

Venus and the Moon in evening twilight, approximately half an hour after sunset
Venus and the Moon in evening twilight, approximately half an hour after sunset. For the Grand Traverse area of Michigan that would be about 6 PM, November 6, 2024. Created using Stellarium.
The Moon tonight as it might appear in a small telescope
The Moon tonight as it might appear in a small telescope. Selected features ae labeled. Created using Stellarium, LibreOffice Draw, and GIMP.
Jupiter and Saturn in this panorama from northeast to south at 8 pm or about 2 1/2 hours aftet sunset
Jupiter and Saturn in this panorama from northeast to south at 8 pm or about 2 1/2 hours aftet sunset. Created using Stellarium.
Jupiter and Mars among the stars of winter seen in the southwestern sky at 6 AM, or about an hour and a half before sunrise, tomorrow morning November 7, 2024. Created using Stellarium.
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 November 6, 2024. Apparent diameters: Venus 14.7″, 77.4% illuminated; Saturn 18.5″, its rings 42.3″, 5.3 degrees from edge on (opening up a bit); Jupiter 46.7″; Mars, too small to be represented here, is 9.6″. 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).
The naked-eye planets and the Moon at sunset and sunrise on a single night, starting with sunset on the right on November 6, 2024. The night ends on the left with sunrise on the 7th. 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, November 6 and 7, 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: Ephemeris Program, Naked-eye planets, Observing, Planets Tags: , , , ,

Ephemeris: 11/05/2024 – Bright Jupiter is now seen earlier in the evening

November 5, 2024 Comments off

This is Ephemeris for Election Day, Tuesday, November 5th. Today the Sun will be up for 9 hours and 58 minutes, setting at 5:25, and it will rise tomorrow at 7:28. The Moon, 4 days before first quarter, will set at 7:51 this evening.

There’s a bright star in the east these evenings. It is extremely bright. If Venus wasn’t around in the evening in the southwest, one might mistake it for Venus. Well this bright star is not a star at all, but the planet Jupiter. Jupiter is the solar system’s largest planet. It is by and large the easiest planet to observe with a small telescope, which will also reveal four of its many moons, which I think is approaching 100 now. (It’s hard to keep track of them.) These four moons were the same ones discovered by Galileo over 400 years ago. Jupiter’s moons move quite rapidly compared to the Earth’s moon. From night to night Jupiter’s moons shift around. Their motions can also be detected over the period of an evening, or night.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

An animated Jupiter finding chart, showing first the stars and the planet Jupiter as they would be seen at 8 PM or about two and a half hours after sunset looking low in the east-northeast. The second frame show the star and planet names, constellation lines for Auriga the Charioteer and Taurus the bull. The two famous star clusters are also named: the Pleiades or Seven Sisters and the Hyades, the face of Taurus. The star clusters and Jupiter are rewarding sights in binoculars. Created using Strellarium, Libreoffice Draw and GIMP.

Categories: Ephemeris Program, Jupiter, Observing Tags:

Ephemeris: 11/04/2024 – The Milky Way in Autumn

November 4, 2024 Comments off

This is Ephemeris for Monday, November 4th. Today the Sun will be up for 10 hours and 1 minute, setting at 5:26, and it will rise tomorrow at 7:26. The Moon, 4 days past new, will set at 6:58 this evening.

As of yesterday the sunsets and sunrises have slipped back an hour so we have darker evenings and brighter mornings, as we came back to Standard Time. It seems odd that we spend less time of the year under Standard Time than we do under Daylight Time. Anyway, looking at the evening sky we see that Venus tonight will be above the four-day-old crescent Moon in the southwest after sunset. By 7 PM the northernmost star of the Summer Triangle, Deneb in Cygnus the swan or the Northern Cross, will be almost directly overhead. And the Milky Way at that time will run from northeast, overhead to the southwestern horizon. Remember tomorrow is Election Day. Make sure you cast your ballot before the end of voting tomorrow, if you haven’t already.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.

Addendum

The dome of the sky at 7:00 this evening,
The dome of the sky at 7:00 this evening, November 4th 2024, in four frames. The first showing only the stars and the Milky Way. The second labeling the first magnitude stars, the planet Saturn and the zenith with a cross with the letter Z. The third showing the outlines of the constellations along the Milky Way. The fourth adds the constellation names. Created using Stellarium and GIMP.
Categories: Ephemeris Program, Milky Way, Observing Tags: , ,

Ephemeris: 11/01/2024 – Grand Traverse Astronomical Society Meeting tonight

November 1, 2024 Comments off

This is Ephemeris for Friday, November 1st. The Sun will rise at 8:21. It’ll be up for 10 hours and 9 minutes, setting at 6:30. The Moon is new today, and won’t be visible.

The Grand Traverse Astronomical Society will host its November meeting tonight at 8:00 PM at Northwestern Michigan College’s Joseph H Rogers Observatory. This will be an unstructured meeting, and a good time for anyone interested to ask knowledgeable members anything about the sky or, since Christmas is coming, about what kind of telescope to buy. Afterward, about 9 PM if it’s clear, there will be viewing of the heavens through the observatory’s telescopes, featuring Saturn, Jupiter and the wonders of the Milky Way, including nebulae, open and globular star clusters, containing hundreds to hundreds of thousands of stars. The observatory is located on Birmley Rd. South of Traverse City between Garfield and Keystone roads.

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

One of the discussion items will be the currently active sun in how it affects the earth.

Photo of a recent aurora taken from the grounds of Northwestern Michigan College's Joseph Rogers Observatory
Jerry Dobek’s photo of a recent aurora taken from the grounds of Northwestern Michigan College’s Joseph Rogers Observatory.
Another photo of the same auroral display
Another photo of the same auroral display from Jerry Dobek.
Categories: Aurorae, Ephemeris Program, GTAS Outreach Event, Sun Tags: ,