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11/08/2022 – Ephemeris – Solar Eclipses in our future

November 8, 2022 Comments off

This is Ephemeris for Election Day, Tuesday, November 8th. Today the Sun will be up for 9 hours and 51 minutes, setting at 5:22, and it will rise tomorrow at 7:31. The Moon, at full today, will rise at 5:28 this evening.

If you are listening to me early this morning, and it’s clear there is a lunar eclipse in progress. The eclipse will be total before 6:41 am, and partial until the Moon sets at 7:40 am. We will have to wait until March 2025 to see the next total lunar eclipse from our area.

However, we will be able to see two partial solar eclipses in the next year and a half. The first is October 14th, 2023. Nearly half of the Sun will be blocked by the Moon for us. The next one is the big one! April 8th, 2024 is a total eclipse less than a day’s drive away. The path of totality runs from Texas to Maine, just clipping the southeast corner of Michigan. Here in Northern Michigan, nearly 90% of the Sun will be covered by the Moon, so it will get noticeably dark at the peak of the eclipse.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 5 hours). They may be different for your location.

Addendum

Areas on the Earth where the solar eclipse of October 14, 2023 can be seen via animation

Areas on the Earth where the solar eclipse of October 14, 2023 can be seen via animation. The gray area is where the partial eclipse is visible. The dot is the place where the ring of the annular eclipse can be seen. Credit: NASA, A. T. Sinclair.

Areas on the Earth where the solar eclipse of April 8, 2024 can be seen via animation

Areas on the Earth where the solar eclipse of April 8, 2024 can be seen via animation. The gray area is where the partial eclipse is visible. The dot is the place where the totally eclipsed Sun can be seen. Credit: NASA, A. T. Sinclair.

For more information on solar and lunar eclipses past and present, go here, NASA’s Eclipse Website.

11/07/2022 – Ephemeris – There will be a total eclipse of the Moon in the hours before sunrise tomorrow morning

November 7, 2022 Comments off

This is Bob Moler with Ephemeris for Monday, November 7th. Today the Sun will be up for 9 hours and 54 minutes, setting at 5:23, and it will rise tomorrow at 7:30. The Moon, 1 day before full, will set at 7:40 tomorrow morning.

There will be a total eclipse of the Moon tomorrow morning. We in Michigan are near the eastern edge of the part of the Earth that can see the eclipse. The partial phase will begin at 4:09 am. More and more of the Moon will enter the Earth’s inner shadow, until 5:16 am, when the Moon will be completely eclipsed. We expect the Moon to have a reddish hue from sunlight leaking and bent through Earth’s atmosphere into the shadow. This total phase will last until 6:41 am, when the Moon will begin to emerge into sunlight to start the ending partial phase of the eclipse. By this time, the Moon will be getting low in the west. The Moon will set around 7:40 am, just before the end of the eclipse and a few minutes after sunrise.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 5 hours). They may be different for your location.

Addendum

Credit: NASA/GSFC, Fred Espenak. Click on the image for the full size PDF file from the NASA eclipse site.

The contact times again for Eastern Standard Time

Contact                     Time EST
U1 Partial eclipse starts...4:09 am
U2 Totality starts..........5:16 am
   Mid-eclipse..............6:00 am
U3 Totality ends............6:41 am
U4 Partial eclipse ends.....7:49 am

P1 and P4 are not noticeable, so are not listed. The penumbral shadow will be noticeable, generally for a half hour or so before U1 and again for a half hour or so after U4, if you are located far enough west of here to see the complete eclipse.

Lunar eclipse diagram

This is a not-to-scale diagram of the motion of the moon through the Earth’s shadow during a lunar eclipse. Assume we are looking down from the north, the motion of the Moon will be counterclockwise. The Moon will enter the shadow from the west or right, so the first “bite” of the shadow will be on the left side of the Moon. The penumbra is a gradually increasing shadow from the outer edge to the umbra, where the Sun is partially blocked by the Earth.

The Moon’s appearance in totality

The Moon will normally appear to have a dull reddish hue during totality, though the edge of the umbra will normally appear gray. When there is a spectacular volcanic eruption, the volcanic dust in the atmosphere can produce an especially dark eclipse. The normal red color is due to all the sunrises and sunsets occurring on the Earth during the eclipse. The atmosphere scatters out the blue component of the sunlight, giving us red sunrises and sunsets. Also, the atmosphere refracts or bends the sunlight into the Earth’s inner shadow, the umbra, at the Moon’s distance, so the totally eclipsed Moon isn’t completely dark.

11/02/2022 – Ephemeris – Let’s see where the naked-eye planets have wandered off to this week

November 2, 2022 Comments off

This is Bob Moler with Ephemeris for Wednesday, November 2nd. The Sun will rise at 8:22. It’ll be up for 10 hours and 7 minutes, setting at 6:29. The Moon, 1 day past first quarter, will set at 2:38 tomorrow morning.

Let’s see where the naked-eye planets have wandered off to this week. Jupiter and Saturn will be visible this evening, in the southeastern sky with the bright moon between them, as soon after sunset as it will be dark enough to see them, which would be by 7:45 pm. Jupiter is the brighter of the two to the left of the Moon, while dimmer Saturn is closer to the Moon on the right. The red planet Mars, though a morning planet, will rise tonight at 8:46 pm in the northeast. It’s located between the tips of the long horns of Taurus the bull, slowly moving northward between those horn tip stars in its big torn to the west among the stars. By seven tomorrow morning, the red planet Mars will be fairly high in the southwestern sky, above and right of the winter constellation of Orion.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Planets in the evening

Planets and the Moon visible in the evening. Jupiter and Saturn in the south with Mars, rising in the northeast. Mars is not yet an evening planet. It’s still more than a month away from rising before sunset and becoming one. Click on the image to enlarge it. Created using Stellarium and GIMP.

The Moon in binoculars

The Moon as it might be seen in binoculars or small telescope tonight, November 2, 2022 with labels of prominent features. Created using Stellarium, LibreOffice Draw and GIMP.

Translations of some lunar feature names according to Virtual Moon Atlas

Mare Crisium – Sea of Crises
Mare Fecunditatis – Sea of Fertility
Mare Imbrium – Sea of Showers
Mare Nubium – Sea of Clouds
Mare Serenitatis – Sea of Serenity
Mare Tranquillitatis – Sea of Tranquility
Mare Vaporum – Sea of Vapors
Montes Apenninus – Apennines Mountains
Sinus Asperitatis – Golfe des Asperites
Sinus Medii – Bay of the Center

Craters are generally named after astronomers, people of science, or explorers

Note that Mare is pronounced Mar-é

Mars in the morning

Mars in the at 7 am tomorrow morning, November 3, 2022. Created using Stellarium.

Telescopic views of Saturn, Jupiter and Mars

Telescopic views of Saturn Jupiter and Mars (north up) as they would be seen in a small telescope, with the same magnification. The image of Mars doesn’t show it, but the white north polar cap will appear at the top or north limb of Mars. Saturn and Jupiter are shown at 9 pm, Mars at 11 pm. Apparent diameters: Saturn 17.20″, its rings 40.07″; Jupiter 47.37″. Mars 15.34″. Mars’ distance is 56.7 million miles (91.4 million kilometers). The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).

A note on Jupiter and its moons: Before 7:56 pm, Io will be in Jupiter’s shadow. At 8:22 pm, Ganymede’s shadow will begin to cross the face of Jupiter. In the image above, the shadow, a small dot, is seen on the lower left of the disk. Europa’s shadow was on the disk prior to 9 pm. Ganymede’s shadow will leave the disk at 11:08 pm. Shadows cross Jupiter’s disk from east to west (right to left) in this view.

Planets and the Moon 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 November 2, 2022. The night ends on the left with sunrise on the 3rd. Click on the image to enlarge it. Created using my LookingUp app and GIMP.

10/31/2022 – Ephemeris – The perfect Halloween star

October 31, 2022 Comments off

This is Bob Moler with Ephemeris for Halloween, Monday, October 31st. Today the Sun will be up for 10 hours and 13 minutes, setting at 6:32, and it will rise tomorrow at 8:20. The Moon, 1 day before first quarter, will set at 12:02 tomorrow morning.

Not all the ghosts and goblins out tonight will be children. One is out just about every night because it’s a star. Its name is Algol, from the Arabic for Ghoul Star or Demon Star. It’s normally the second-brightest star in the constellation Perseus the hero, visible in the northeast this evening. The star is located where artists have drawn the severed head of Medusa, whom he had slain. Medusa was so ugly that she turned all who gazed upon her to stone. Algol is her still glittering eye. The star got the name before astronomers discovered what was really wrong with it. They found out that it does a slow wink about every two days, 21 hours because Algol is two stars that eclipse each other. Her next evening wink will be dimmest at 10:25 p.m. November 19th.*

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

*For the broadcast, the source for the Algol minimum brightness time was the Stellarium app. For whichever date the sky is displayed for and Algol is clicked on, among the data for the star that is displayed is next minimum light. However, in double-checking the times with those posted in Sky & Telescope magazine after I recorded the program, it turns out to be 3 hours 46 minutes early, so minimum light would be at 1:36 am on November 17th. At the time given then, the eclipse would just be starting. The actual first eclipse minimum in the evening in November would be at 10:25 pm on the 19th. I hope it’s clear on the night of the 16/17th to see which prediction is right. In the past, S&T was accurate, or accurate enough.

Algol Finder

Perseus, Cassiopeia, Andromeda with Algol finder animation for Autumn evenings. Click on the image to enlarge it. Created using Stellarium and GIMP.

Perseus and the head of Medusa from the 1690 Uranographia by Johannes Hevelius.

Perseus and the head of Medusa from the 1690 Uranographia by Johannes Hevelius. Note that the captions in the image are as seen in a mirror. Early star representations were painted on a globe, a celestial sphere, so the stars and constellations were shown as seen from the outside. A God’s eye view. Early printed star charts simply kept the convention. I reversed the image, so it is seen from inside the celestial sphere. An Earthly view to match the sky as we see it. The image was found with the article on Algol on Wikipedia.

Eclipsing Binary Star

Animation of an eclipsing binary star like Algol. Credit: Wikimedia Commons h/t Earth and Sky

10/28/2022 – Ephemeris – Mars is turning around this weekend

October 28, 2022 Comments off

This is Bob Moler with Ephemeris for Friday, October 28th. Today the Sun will be up for 10 hours and 21 minutes, setting at 6:37, and it will rise tomorrow at 8:16. The Moon, 3 days past new, will set at 8:39 this evening.

This Sunday the 30th, the planet Mars will cease its normal eastward motion in relation to the stars, and backtrack to the west for a while. The instant Mars stops its eastward motion, it is said to be stationary. The backtracking is called retrograde motion, which was hard for ancient astronomers to explain because they thought the Earth was not moving and in the center of the universe. And the planets moved in uniform circular motion. So said the Greeks, because they thought that things in the heavens were perfect, not like the imperfect things of the Earth. Mars was a hard case. Its motion was definitely not uniform or circular. To Copernicus, the retrograde motion meant that the Earth was a planet passing another planet in their race around the Sun.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Mars retrograde path 2022-2023

Mars retrograde path from October 29, 2022 to January 11, 2023 against the stars of Taurus the bull. It will be at opposition on December 7, and actually closest to the Earth on November 30 at 50.61 million miles or 81.45 million kilometers. In the upper right is the beautiful Pleiades star cluster, also known as the Seven Sisters. Below and right is the V shaped star cluster that represents the face of Taurus the bull, with the bright red star Aldebaran as the bull’s angry red eye. That V of stars is called the Hyades, who in mythology were the half sisters to the Pleiades. Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts) and GIMP.

10/27/2022 – Ephemeris – Trying to spot the young Moon tonight

October 27, 2022 Comments off

This is Bob Moler with Ephemeris for Thursday, October 27th. Today the Sun will be up for 10 hours and 24 minutes, setting at 6:38, and it will rise tomorrow at 8:15. The Moon, 2 days past new, will set at 7:55 this evening.

The Moon is again making its appearance in the evening sky as a thin crescent. The crescent appearance is because the moon is mostly between the Earth and the Sun. So we are seeing mostly its night side, with just a sliver of it being sunlit. But the Moon has the Earth in its sky, which is quite big and bright, much brighter than the Moon in our skies. And when the Moon’s phase is thin, the Earth, having the opposite phase, will be a nearly full gibbous orb. The Earth illuminates the Moon’s night side with earthlight. We call it earthshine, when the whole Moon appears faintly inside the crescent. It’s also known more poetically as the “Old moon in the new moon’s arms.” If you’re not sure, because the effect is faint, check it out in binoculars. The effect should last another night.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Earthshine by Bob Moler

An old picture of mine overexposing the crescent Moon to bring out earthshine. The moon was a wider crescent than it will appear to be tonight.

10/26/2022 – Ephemeris – Let’s see where the naked-eye planets have wandered off to this week

October 26, 2022 Comments off

This is Bob Moler with Ephemeris for Wednesday, October 26th. Today the Sun will be up for 10 hours and 27 minutes, setting at 6:40, and it will rise tomorrow at 8:14. The Moon, 1 day past new, will set at 7:21 this evening.

Let’s see where the naked-eye planets have wandered off to this week. Jupiter and Saturn will be visible this evening, in the east-southeast and south-southeast respectively, as soon after sunset as it will be dark enough to see them, which would be by 7:45 pm. Jupiter is seen against the stars of Pisces the fish, while Saturn is spotted in the eastern end of Capricornus the sea goat. The red planet Mars, though a morning planet, will rise tonight at 9:15 pm in the northeast. It’s located between the tips of the long horns of Taurus the bull. By seven tomorrow morning, the red planet Mars will be high in the southwestern sky, above the winter constellation of Orion. Mars has traveled about as far east as it will get for a while. It will head back westward after Sunday.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Evening planets label animation

Jupiter and Saturn with label animation for 8 pm tonight, October 26, 2022. Click on the image to enlarge it. Created using Stellarium and GIMP.

Mars at 11 pm

Though Mars is a morning planet, since it is in the sky at sunrise, perhaps the best time to vies it is in the evening after it rises in the east-northeast at 9:15 pm. By 11 pm, as seen here, Mars should be high enough to present a decent image in a telescope. Click on the image to enlarge it. Created using Stellarium.

Telescopic views of Saturn, Jupiter and Mars

Telescopic views of Saturn Jupiter and Mars (north up) as they would be seen in a small telescope, with the same magnification. The image of Mars doesn’t show it, but the white north polar cap will appear at the top or north limb of Mars. Saturn and Jupiter are shown at 8 pm, Mars at 11 pm. Apparent diameters: Saturn 17.41″, its rings 40.55″; Jupiter 48.16″. Mars 14.58″. Mars’ distance is 59.7 million miles (96.2 million kilometers). The ” symbol means seconds of arc (1/3600th of a degree.) Click on the image to enlarge it. Created using Cartes du Ciel (Sky Charts).

Planets and the Moon 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 26, 2022. The night ends on the left with sunrise on the 27th. Click on the image to enlarge it. Created using my LookingUp program and GIMP.

10/24/2022 – Ephemeris – Finding Pisces the fish

October 24, 2022 Comments off

This is Bob Moler with Ephemeris for Monday, October 24th. Today the Sun will be up for 10 hours and 33 minutes, setting at 6:43, and it will rise tomorrow at 8:11. The Moon, 1 day before new, will rise at 8:18 tomorrow morning.

High in the southeast at 9 p.m. are the four bright stars of the Great Square of Pegasus, the upside down flying horse. Lying along the left and bottom sides of the great square is the constellation of Pisces the fish, one of the constellations of the Zodiac that lie along the path of the Sun, Moon and planets. Even though the constellation is called the fish, the fish themselves are not well represented in the stars. What can be traced in the stars is the rope, that’s tied to their tails, anchored at the extreme southeastern part of the constellation. The right or western end of Pisces is the asterism, or informal constellation, of the Circlet. A loop of 5 stars, the rope around the tail of one of the fish, or the fish itself. Jupiter is seen against the stars of Pisces in the evening, the rest of this and early next year.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Pisces finder animation

Pisces finder animation looking south-southeast with Jupiter at 9 pm tonight, October 24, 2022. Created using Stellarium and GIMP.

10/21/2022 – Ephemeris – Lots of transient astronomical activity this weekend

October 21, 2022 Comments off

This is Bob Moler with Ephemeris for Friday, October 21st. Today the Sun will be up for 10 hours and 41 minutes, setting at 6:48, and it will rise tomorrow at 8:07. The Moon, halfway from last quarter to new, will rise at 4:44 tomorrow morning. | We have several astronomical events happening tonight and over the weekend. The Orionid meteor shower may still be at peak, appearing tonight between 11 pm and moonrise tomorrow morning. Up to 20, and maybe more, meteors per hour may be spotted just prior to moonrise. Tomorrow Venus will be in superior conjunction with the Sun, the passing behind, though not directly behind the Sun, and thus entering the evening sky. It will be a month or so for Venus to separate itself from the Sun’s glare to be spotted in the early evening. Finally, on Sunday Saturn will end its retrograde or westward movement against the stars of Capricornus and resume moving eastward, its normal motion around our sky.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Orionid radiant

The Orionid meteor shower radiant. The radiant rises at 11 p.m., so the meteors will be visible from then into morning twilight. Despite the location of the radiant, the meteors will b e seen all over the sky. However, true Orionids can be traced back to the radiant point. This chart is from another year. This year, bright Mars would be at the top center of the image. Created using Stellarium.

Venus near Superior conjunction- SOHO LASCO C2 Coronagraph

Venus near Superior conjunction through the Solar and Heliospheric Observatory (SOHO) LASCO C2 Coronagraph. The white circle inside the occulting disk is the diameter of the Sun’s photosphere, the disk we see of the Sun in white light. Launched in 1995, SOHO has been in halo orbit around the Sun-Earth L1 Lagrange point ever since.

Saturn stationary animation

Saturn stationary animation showing it with and without annotations. The fine, folded line with tick marks is Saturn’s path. The tick marks are at 10-day intervals. Saturn starts out in retrograde motion, heading westward or to the right. On October 23rd, it slows and stops that motion. It begins to head back eastward in its normal prograde motion to the left. Outer planets like Saturn, Jupiter, Mars and the rest exhibit retrograde motion when the Earth in effect passes them on the same side of the Sun. Click on the image to enlarge it slightly. Created using Cartes du Ciel (Sky Charts), LibreOffice Draw, and GIMP.

10/20/2022 – Ephemeris – Halley’s Comet returns… in little bitty pieces

October 20, 2022 Comments off

This is Bob Moler with Ephemeris for Thursday, October 20th. Today the Sun will be up for 10 hours and 44 minutes, setting at 6:49, and it will rise tomorrow at 8:06. The Moon, 3 days past last quarter, will rise at 3:36 tomorrow morning.

Halley’s Comet is back! (Pronounced Hawley’s) Well sorta. In the form of the Orionid meteor shower. Bits of Halley’s Comet from previous passes by the Earth’s orbit make their twice-yearly show in our skies as these bits collide with the Earth’s atmosphere. Halley’s orbit passes close to the Earth’s orbit at points where the Earth is around May 6th and again near October 21st. Light dust and ionized gas get blown back into the tail of the comet. Heavier particles will roughly follow in the comet’s orbit. The radiant, a spot above the constellation Orion and below Gemini from which they will seem to come, will rise around 11 pm. So view them any time after that as their numbers will increase until the Moon rises both tonight and tomorrow nights.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT – 4 hours). They may be different for your location.

Addendum

Orionid radiant

The Orionid Radiant is high in the south at 5 a.m. this weekend. Created using Stellarium.

Halley's Comet Orbit and meteor showers

Halley’s Comet 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. Click on the image to enlarge it. Diagram credit JPL Small-Body Database Browser with my annotations.