Archive

Archive for February, 2023

02/14/2023 – Ephemeris Extra – Back in the hospital again

February 14, 2023 2 comments

It’s the cost of getting old. I hope to get back soon. Happy St Valentine Day!

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02/13/2023 – Ephemeris – Follow the Drinking Gourd

February 13, 2023 Comments off

This is Bob Moler with Ephemeris for Monday, February 13th. Today the Sun will be up for 10 hours and 21 minutes, setting at 6:08, and it will rise tomorrow at 7:44. The Moon, at last quarter today, will rise at 2:51 tomorrow morning.

In the decades before the Civil War, runaway slaves would travel, often at night, northward from the slave states in the south to the northern free states and Canada over the metaphorical Underground Railroad following the Drinking Gourd, the Big Dipper as their compass. For millennia, the North Pole of the sky had been passing near the handle of the Big Dipper or bear’s tail. As an amateur astronomer, who loves the dark, starlit skies, I’ve noticed that everyone is the same color in the dark! This year the Grand Traverse Astronomical Society will, once again, team with the Sleeping Bear Dunes for more Sun and star parties.

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

Addendum

Runaway slaves following the Drinking Gourd

“Follow the Drinking Gourd,” a show at the Virginia Living Museum’s Abbit Planetarium based on Jeanette Winter’s children’s book of the same name, tells the story of a slave family who used the stars to make their way north. Visitors can watch the free show Saturdays in February. (Courtesy of Virginia Living Museum) Via Daily Press, Newport News, VA.

02/10/2023 – Ephemeris – Finding Orion’s greater hunting dog, Canis Major

February 10, 2023 Comments off

This is Bob Moler with Ephemeris for Friday, February 10th. Today the Sun will be up for 10 hours and 13 minutes, setting at 6:04, and it will rise tomorrow at 7:49. The Moon, 3 days before last quarter, will rise at 11:14 this evening.

The great winter constellation or star group, Orion the hunter, is located in the southern sky at 9 p.m. His elongated rectangle of a torso is vertical. In the center of the rectangle are three stars in a line that make his belt. As a hunter, especially one of old, he has two hunting dogs. The larger, Canis Major, can be found by following the three belt stars of Orion down and to the left. They point to Sirius, the brightest nighttime star, also known as the Dog Star. It’s in the heart of a stick figure dog low in the southeast facing Orion that appears to be begging. There’s a fine star cluster, called Messier, or M 41, at the 5 o’clock position from Sirius. It’s easily visible in binoculars or a small telescope.

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

Addendum

Orion and Canis Major

Orion and Canis Major animation for earlier than 9 in the evening. Created using Stellarium and GIMP.

02/09/2023 – Ephemeris – Orion’s Belt stars

February 9, 2023 Comments off

This is Ephemeris for Thursday, February 9th. Today the Sun will be up for 10 hours and 10 minutes, setting at 6:02, and it will rise tomorrow at 7:50. The Moon, halfway from full to last quarter, will rise at 10:07 this evening.

Orion’s belt of three stars is one of the most noticeable star groupings in the sky. There are no other groups of three bright stars in a straight line visible anywhere else in the sky. The star’s names from left to right are Alnitak, Alnilam and Mintaka. They are actually a bit farther away than the other bright stars of Orion. Alnilam, the center star, is over three times the distance of red giant Betelgeuse above them and over twice as far as blue white giant star Rigel below them. Alnilam is 375 thousand times brighter than the Sun according to the SIMBAD Astronomical Database. These three stars were also known as Frigga’s Spindle by the Norsemen. Frigga also known as Freya is the goddess from which we get the name of the day of the week Friday.

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

Addendum

Orion's named stars

Orion’s named stars, including the belt stars. Created using Stellarium.

02/08/2023 – Ephemeris – Let’s find where the naked-eye planets have wandered off to this week

February 8, 2023 Comments off

This is Bob Moler with Ephemeris for Wednesday, February 8th. Today the Sun will be up for 10 hours and 7 minutes, setting at 6:01, and it will rise tomorrow at 7:52. The Moon, 3 days past full, will rise at 9:02 this evening.

Let’s find where the naked-eye planets have wandered off to this week. Very early after sunset, Venus can be spotted low in the southwest by 6:30 pm. Mars, and Jupiter will be visible this evening by 7 pm. Mars will be above Orion in the southeast and is pulling away from the Pleiades. Jupiter will be in the southwest. Saturn is way below Venus now, so it’s gone until it reappears in the morning sky in a few months. It will make the crossing to the morning sky with its solar conjunction on the 16th. Jupiter will cross paths with Venus on March 1st. Mercury is now in the morning sky, but too close to the Sun to be visible.

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

Addendum

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 February 8, 2023. The night ends on the left with sunrise on the 9th. Click on the image to enlarge it. Created using my LookingUp app and GIMP.

02/07/2023 – Ephemeris – A new view on the creation of our Moon

February 7, 2023 Comments off

Feb 7. This is Bob Moler with Ephemeris for Tuesday, February 7th. Today the Sun will be up for 10 hours and 5 minutes, setting at 5:59, and it will rise tomorrow at 7:53. The Moon, 2 days past full, will rise at 7:58 this evening.

Is this how the Moon came to be? After the Apollo missions, NASA decided to look at the crust of the Moon which apparently is much like the Earth’s and came up to the conclusion that the Moon was formed by a collision with the Earth by a Mars sized body that they’ve called Thea, named after the mother of the twins Apollo and Artemis. It crashed into the Earth at about a 45-degree angle, and caused a ring of debris around the Earth that would be maintained for a long time. In a newer simulation, the collision could actually create two blobs of material, a large one that became our Moon, in orbit, with about one percent of the Earth’s mass, and a smaller mass that fell back onto the Earth.

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

Addendum

New moon formation

A new simulation on how the Moon formed. Credit: PBS.

02/06/2023 – Ephemeris – The Persephone Period is ending

February 6, 2023 Comments off

This is Ephemeris for Monday, February 6th. Today the Sun will be up for 10 hours and 2 minutes, setting at 5:58, and it will rise tomorrow at 7:54. The Moon, 1 day past full, will rise at 6:53 this evening.

All over the Interlochen Public Radio broadcasting region, the Persephone period is ending. What’s the Persephone period? The Persephone period is a time when the daylight hours drop below 10 hours a day. Around here, this would affect natural lighted greenhouses, since our world is still covered in snow. This is because plants don’t grow very well with less than 10 hours of sunlight. It is named for the Greek goddess Persephone, who is goddess of crops that are sewn. She was kidnapped by her uncle Hades, the god of the Underworld, and was made his bride and became Queen of the Underworld. However, every time she went down to the underworld all the plants on the surface of the earth died, so Zeus made an arrangement with Hades that she could only be in the underworld for part of the year.

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

Addendum

Persephone statue

Statue of Persephone-Isis at the Heraklion Archaeological Museum, Crete. Credit: Wolfgang Sauber.

In the Interlochen/ Traverse City area, the Persephone period runs from about November 5th to about February 6th. Of course, we make up for it in late spring and early summer with up to 15 1/2 hours of daylight near the summer solstice.

02/03/2023 – Ephemeris – Space Rocks with Joe Brooks

February 3, 2023 Comments off

This is Ephemeris for Friday, February 3rd. Today the Sun will be up for 9 hours and 54 minutes, setting at 5:54, and it will rise tomorrow at 7:58. The Moon, 2 days before full, will set at 7:54 tomorrow morning.

Space Rocks with Joe Brooks, will be presented by, the Grand Traverse Astronomical Society’s own meteorite expert, Joe Brooks, at this evening’s meeting of the Grand Traverse Astronomical Society at 8 p.m. at Northwestern Michigan College’s Rogers Observatory. He even has a meteorite of a type called Howardite, that the Dawn spacecraft, which orbited the asteroid Vesta, has determined to be from there. Everyone is welcome. And there is a Zoom component to attend remotely. A link and instructions will be found on the society’s website, gtastro.org. This year, again, the society will be teaming up with the Sleeping Bear Dunes National Lakeshore for star parties this late spring, summer, and early fall.

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

Categories: Uncategorized

02/02/2023 – Ephemeris – It’s Groundhog Day again

February 1, 2023 Comments off

This is Ephemeris for Groundhog Day, Thursday, February 2nd. Today the Sun will be up for 9 hours and 51 minutes, setting at 5:52, and it will rise tomorrow at 7:59. The Moon, 3 days before full, will set at 7:16 tomorrow morning.

I’m not sure if Punxsutawney Phil will see his shadow this morning or not, but February 2nd was a special day to the ancients. It is also Candlemas day for the Catholic Church. It is also celebrated as a cross-quarter day. The middle of the season of Winter, though the exact date of the middle of winter is the 4th. And if Phil sees his shadow, and we do get 6 more weeks of winter, that’s OK too. By the calendar, it’s actually more like 6 ½ weeks to the vernal or spring equinox and the official end of winter. Of the other cross-quarter days, only one stands out today. It’s May 1st, May Day. The way this year has been going, winter has had a hard time getting started. The temperatures are above normal and the snowfall below normal.

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

Addendum

Ground Hog Day

Poor Punxsutawney Phil, rousted out of his mid winter nap. They might be in the middle of a blizzard today. Credit: http://www.fuzzytoday.com

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02/01/2023 – Ephemeris – Let’s find where the naked-eye planets have wandered off to this week

February 1, 2023 Comments off

This is Ephemeris for Wednesday, February 1st. Today the Sun will be up for 9 hours and 49 minutes, setting at 5:51, and it will rise tomorrow at 8:00. The Moon, halfway from first quarter to full, will set at 6:31 tomorrow morning.

Let’s find where the naked-eye planets have wandered off to this week. Very early after sunset. Venus can be spotted low in the southwest by 6:30 pm. Mars, and Jupiter will be visible this evening by 7 pm. Mars will be above Orion in the southeast and is pulling away from the Pleiades. Jupiter will be in the southwest. Saturn is way below Venus now, so it’s gone until it reappears in the morning sky in a few months. It will make the crossing to the morning sky with its solar conjunction on the 16th. Mercury is now in the morning sky. It has a few more days visibility around 7 am in the southeastern sky after reaching greatest western elongation from the Sun last Sunday.

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

Addendum

Venus in twilight

Venus low in the west-southwestern twilight at 6:30 pm tonight, February 1, 2023. Created using Stellarium.

Evening planets at 7 pm

Evening planets at 7 pm tonight, February 1, 2023. The orange line is the ecliptic, which is the plane of the Earth’s orbit. The sun appears on that line throughout the year. Notice that all the other planets are very close to that line. That is an artifact of the accretion disk from which the planets formed some 4 1/2 billion years ago. The planets still maintain the nearly same plane for their existence to this day. Click on the image to enlarge it. Created using Stellarium.

Annotated gibbous Moon tonight

The gibbous Moon tonight at 7:00 pm, labeled. Created using Stellarium, LibreOffice Draw, and GIMP.

This is what Mercury might look like in the southeast around 7:20 tomorrow morning, February 2nd from Interlochen/Traverse City. At that time, it’ll be 5 degrees above a sea horizon, which is half the width of a fist held at arm’s length. Any trees of course will reduce it. Created using Stellarium.

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 February 1, 2023. The night ends on the left with sunrise on the 2nd. Click on the image to enlarge it. Created using my LookingUp app and GIMP.