Archive for the ‘Ephemeris Extra’ Category

Ephemeris Extra – Sunrise solar eclipse

June 10, 2021 Comments off
The partially eclipsed Sun this morning

The partially eclipsed Sun this morning, taken through a solar filter, so it’s redder than it actually was. Taken shortly after 6 am from Traverse City, MI West Middle School. There were quite a bit of clouds on the horizon. Credit Bob Moler.

Here is an unfiltered view taken a few minutes earlier:

Sunrise solar eclipse

Here is an unfiltered shot of the Sun bisected by a cloud. Credit Bob Moler.

12/11/2020 – Ephemeris Extra – Venus will hide behind the Moon for W US, Canada and N Pacific Tomorrow

December 11, 2020 Comments off

Tomorrow Saturday, December 12, 2020 Venus will be occulted, or covered, by the thin crescent Moon for the area bounded in the map below. The southern boundary is a thin red line denoting that the event will take place in daylight.  For safety sake observe the event from the shadow of a building open to the sky west of the Sun to not inadvertently point binoculars or telescope toward the Sun and cause permanent damage to your eyes. Venus is visible in the daytime. A program like Stellarium will help in locating Venus and determination of the time of the event for your location. Also, for Stellarium, in the configuration window’s Tool tab make sure “Topocentric coordinates” is checked.

The event will NOT be visible from Michigan.

Occultation of Venus World map 12/12/2020

Occultation of Venus World map 12/12/2020. The occultation will be visible within the bounded area. For the area that looks like a lazy figure 8 the occultation will start (on the left) or end as Venus and the Moon rises or sets. For most areas within the bounded area the occultation is a daytime event. Credit Occult4.


12/03/2020 – Ephemeris Interruptus – I’m in the hospital for tests

December 3, 2020 1 comment

Yesterday I developed some symptoms of the stroke I had last January and my daughter took me to the ER where I had a CT scan. I’m waiting on a early am MRI. I should be home later today. I hope to be finishing up my Zoom program In Search of the Star of Bethlehem. If you’re interested go to Friday. The program will start ar 8 pm EST, though you can join earlier with the GTAS business meeting in progress. I might get the 12/03 post up later in the day.

The audio Ephemeris programs will run on Interlochen Public Radio through Monday regardless of my health issues. They’re already in the can, so to speak.

11/17/2020 – Ephemeris – The Pleiades in legends from different cultures

November 17, 2020 Comments off

This is Ephemeris for Tuesday, November 17th. Today the Sun will be up for 9 hours and 29 minutes, setting at 5:12, and it will rise tomorrow at 7:44. The Moon, 2 days past new, will set at 7:23 this evening.

Let’s look at how some other cultures saw the Pleiades, the star cluster that is seen in the eastern sky these evenings. To the Anishinaabe native peoples around here the Pleiades is the “Hole in the Sky” or the seven stones that are heated for the sweat lodge ceremony. To the Kiowa these were sister stars that had been whisked into the sky from the top of Devils Tower in Wyoming where they were threatened by a huge bear. In Norse mythology these were the goddess Freya’s hens. The name we know them by has rather misty origins. Some think the Greek name is from the mother of the seven sisters, Pleione. The Greek word for sail is similar to Pleiades, and it seems the appearance of the Pleiades in the morning sky saw the best sailing weather in the Mediterranean.

The event times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


Devil's Tower

Seven maidens being attacked by a giant bear, having fled to the top of Devil’s Tower in Wyoming. Painting by Herbert Collins,

The Pleiades, about what you'd see in binoculars.

The Pleiades, about what you’d see in binoculars, more than the 6 or 7 stars visible to the naked eye. The brighter stars are Freya’s Hens and also the Seven Sisters and Indian maidens. Credit Bob Moler.

Pleiades finder animation

Pleiades finder animation looking east about 8 pm in mid-November. Created using Stellarium.

02/17/2020 – Ephemeris Extra – The Moon will cover the planet Mars in morning twilight tomorrow, Tuesday the 18th.

February 17, 2020 Comments off

Sorry, I missed this until now. Tomorrow morning the 18th Mars will be occulted by the Moon. For Northern Lower Michigan Mars will disappear shortly after 7:10 a.m. The exact time depends on your location, so I can’t be more specific.  At that time the Moon and Mars will be in the southeastern sky. Mars is now first magnitude, but will fare poorly in the morning twilight, so I’d suggest finding the Moon and Mars at least 15 minutes earlier with binoculars or telescope. Mars will reappear at the Moon’s unlit side around 8:37 a.m. This is after sunrise, so a telescope will be required to spot it.  Hoping for clear skies, though the weather forecast isn’t promising.

Occultation map

A map of where the occultation of Mars will be visible. Created using Occult4.

Mars Occultation Start

Where Mars will disappear at the Moon’s sunlit edge. Created using Stellarium.

Mars Occultation End

Mars will reappear at the Moon’s unlit edge around 8:36 a.m. give or take. Created using Stellarium.

02/10/2020 – Ephemeris Extra – Back again

February 10, 2020 4 comments

I’m now back home and will continue my therapy at home or as an outpatient.  I can now walk unaided but they’d prefer that I use a walker.  I want to thank the doctors, nurses, therapists and assistants at Mary Free Bed Rehabilitation at Munson Medical Center in Traverse City, MI for getting me back this far so fast.  I also want to thank those who called and wrote to Interlochen Public Radio about missing the program.  I missed it too.  The programs will air again starting tomorrow with a look at Mercury in the evening.  Also to those who wrote comments on this blog, I thank you.  It means a lot to me.

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01/20/2020 Ephemeris Extra – Ephemeris will be on a short hiatus

January 20, 2020 3 comments

On January 11th I suffered a stroke. It affected my left side and scrambled my brains a bit. I’m in Mary Free Bed Rehabilitation at Munson Medical Center in Traverse City, for a bit to get my left side talking better to my brain. I hope to be back in a month or so. Thanks for the messages of concern sent here and to Interlochen Public Radio.

Bob Moler

p.s. Yesterday’s SpaceX Crew Dragon inflight abort test looked pretty cool!

Categories: Ephemeris Extra

Ephemeris Extra – The Great Star Story of Autumn

September 18, 2019 Comments off
Autumn Star Story Constellations

The constellations of the great star story of autumn. Looking southeast on October 31 at 10 p.m. Created using Stellarium.

The great star wheel of the sky rolls on. In the evening sky gone are the stars of spring, and going are the southern stars of summer. In the morning sky before sunrise the stars of an early winter evening.

A constant in both skies are the stars of autumn: rising in the evening and setting in the morning. In no other part of the sky do so many constellations take part in a single story

The constellations, as seen above are Cepheus, Cassiopeia, Andromeda, Perseus, Pegasus, and Cetus. And their story goes like this:

In distant Ethiopia a crisis was brewing. King Cepheus and Queen Cassiopeia were at wits end as how to stop it. A giant sea monster named Cetus was ravaging the country’s coastal cities destroying them and devouring the inhabitants.

The king and queen consulted the temple oracle as to what happened and what could be done to save their country. The oracle intoned gravely that the fault was Cassiopeia’s. Suddenly the queen knew what happened. Cassiopeia was very beautiful and she had vainly boasted to all who could hear that she was more beautiful than even the sea nymphs, the lovely daughters of the sea god Poseidon.

The sea nymphs had heard of Cassiopeia’s boast and complained to their father. Poseidon, like any father, was angered, and being a god was able to do something about. Being a god means never having to say your sorry when you do something really mean. He loosed the monster Cetus upon the Ethiopians.

The oracle said that to appease the monster and Poseidon Cassiopeia would have to sacrifice her daughter the Princess Andromeda to the monster. That is how young Andromeda was chained to the rocks on the sea shore to await her doom…

Far away in ancient Greece a wedding was about to take place between the beautiful Princess Danaë and King Polydectes. Danaë’s son Perseus, fathered by Zeus, but that’s another story, wasn’t too happy about the proposed union, and Polydectes wanted the boy gone.

When Perseus asked Polydectes what he wanted for a wedding gift, he said, “I want the head of Medusa.” The boy immediately and foolhardedly agreed to get it for him.

Merdusa, it turns out, was one of three sisters, the Gorgons, who had snakes for hair. They were so ugly that one glimpse of them would turn the beholder to stone. Medusa was the only mortal one.

Luckily Perseus had the favor of the god Hermes and Athene. They armed him with Hermes’ winged sandals, a helmet that made him invisible, a pouch that would expand to hold an object of any size, a shiny mirror shield, and a sword.

Thus armed Perseus was told to find the Graiae or the gray women, who could tell him where the lair of the Gorgons was. They were three in number and shared but one eye and one tooth among them which they passed from one to another to use.

The Graiae refused to help Perseus. But he was able to force them to help by snatching their one eye while it was being passed from one to another. They told him that the Gorgons dwelt in the shore of the river Ocean at the edge of the world in perpetual twilight.

In approaching the lair of the Gorgons Perseus put on the helmet of invisibility. He approached Medusa stepping backwards, cautiously peering only at Medusa’s indistinct image in his shield. Perseus then swept his sword in a backhanded way and managed to sever Medusa’s head. It is said that Athene guided his hand.

Amazingly, springing full grown from Medusa’s blood was the winged white stallion Pegasus. After placing Medusa’s head in the pouch, Perseus mounted Pegasus for the trip home.

Cruising high in the sky over the Ethiopian coast Perseus spotted a horrific sight. There far below the beautiful Andromeda, in chains; her screams reaching his ears. Then he spotted why she was screaming. A short distance away, crawling out of the surf was the monster Cetus, heading towards Andromeda. Perseus immediately sizes up the situations and swooped with Pegasus down to a spot between Andromeda and the monster. Then, burying his head in his shoulder drew out the head of Medusa from the pouch and held it in front of Cetus. The head was as lethal in death as in life, and the monster was promptly turned to stone. Replacing the head in the pouch, Perseus freed Andromeda. They flew off to, well supposedly, live happily ever after.

Oh yes. Perseus did present the head of Medusa to his step father Polydectes. He, of course, was also turned to stone when he laid eyes on it.

There you have it a story connecting the autumn constellations of Cepheus, Cassiopeia, Andromeda, Perseus, Pegasus and Cetus.

Cepheus is a dim church steeple of a constellation. Its dim star Delta is a variable star, the prototype of an important class of distance measuring stars called Cephieds in its honor. Cassiopeia is the famous W shaped constellation that along with Cepheus doesn’t set at our latitude.

Perseus looks to me more like the cartoon roadrunner than a hero. As the ancients saw him, he is holding the head of Medusa, whose still glittering eye is the star Algol, a variable star which ghastly winks at us every 2 days and 21 hours.

Andromeda’s modern claim to fame is the great galaxy that lies beyond her stars, the Great Andromeda Galaxy which has the designation M31. The galaxy is faintly visible to the unaided eye on dark nights. The farthest you can see without optical aid. The galaxy lies some 2.5 million light years away.

Pegasus can be easily found by the square of stars the form his body. It’s called the Great Square of Pegasus.

What can be said about Cetus. It now represents a whale, not a monster. Its star Mira, which means “Wonderful”, slowly varies in brightness over 330 days from a star barely visible in binoculars to a 2nd or 3rd magnitude star.

Look up on an autumn evening and recapture the wonder the ancients had as they looked upward at the stars.

09/16/2019 – Ephemeris Extra – I’ll be giving my presentation “Apollo and the Moon Race” tonight

September 16, 2019 Comments off

I’ll be giving my illustrated talk Apollo and the Moon Race tonight at 7 p.m. at the Traverse Area District Library on Woodmere Avenue in Traverse City.  The 1960s were a heady time with the space race between the US and the USSR in achieving space firsts.  I will look at the competition, and the incremental steps that had to be made to finally send astronauts to the surface of the Moon on July 20th 1969.

If you miss this presentation, there will be another on Friday September 27, at 7 p.m. at the Betsie Valley District Library in Thompsonville.

Both events will have viewing of the skies with the Grand Traverse Astronomical Society including Jupiter and Saturn afterward if it’s clear.



Announcement: I’m offering to present Apollo and the Race to the Moon to schools, libraries and non-profits

July 2, 2019 Comments off

Apollo and the Race to the Moon is the story of the space race from Sputnik to Apollo 17 between the United States and the Soviet Union that traces the United States’ incremental steps and the Soviets’ rather disorganized approach that allowed the US to be the first on the Moon.  The presentation by yours truly will be illustrated by images and a short video.

I will be giving this presentation as a NASA/JPL Solar System Ambassador.  The presentation will be given free of charge for non-profit groups, libraries and schools.  I can be reimbursed for expenses if traveling over 50 miles from Traverse City, MI.  The presentation lasts a bit over an hour depending on the number of questions, which I welcome.

Apollo and the Race to the Moon Title

Apollo and the Race to the Moon Title slide

I’ve been an avid amateur astronomer and space enthusiast since before the launch of Sputnik, so I have lived through all these events.  For more information on me click on the About link above.  There’s even a timeline of my astronomy activities here.  The About link above contains a contact form where you can reach me.


Categories: Ephemeris Extra