Archive

Archive for October, 2019

10/31/2019 – Ephemeris – The perfect Halloween star

October 31, 2019 Comments off

Ephemeris for Halloween, Thursday, October 31st. Today the Sun will be up for 10 hours and 14 minutes, setting at 6:33, and it will rise tomorrow at 8:20. The Moon, half way from new to first quarter, will set at 9:22 this evening.

Not all the ghosts and goblins out tonight will be children. One is out every night, because it’s a star. Its name is Algol, from the Arabic for Ghoul Star or Demon Star. It’s the second brightest star in the constellation Perseus the hero, rising 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. Astronomers finally found out what was wrong with Algol. It does a slow 6 hour wink every 2 days 21 hours because it is two very close stars that eclipse each other in that period. It’s next nighttime minimum will be 1:46 a.m. on November 12th.

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

Addendum

Algol Finder

Perseus, Cassiopeia, Andromeda with Algol finder animation for Autumn evenings. Created using Stellarium and GIMP.

Eclipsing Binary Star

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

Here is a web sit where you can calculate the minima of Algol and other eclipsing stars:  http://www.astropical.space/algol.php

10/30/2019 – Ephemeris – Our weekly look at the naked eye planets

October 30, 2019 Comments off

Ephemeris for Wednesday, October 30th. Today the Sun will be up for 10 hours and 16 minutes, setting at 6:34, and it will rise tomorrow at 8:19. The Moon, 3 days past new, will set at 8:36 this evening.

Let’s look at the bright planets for this week. Venus and Mercury are too close to the Sun to be seen. They are on the evening or east side of the Sun. Bright Jupiter will be low in the southwestern sky as it gets dark. It will set at 9 p.m. Jupiter is moving at nearly its fastest to the east now and next year will be where Saturn is currently. Saturn, the ringed planet, will be in the south-southwestern sky in the evening, and will set at 10:40 p.m. Next year it will be a bit farther east. Jupiter is approaching Saturn in our sky. They will cross paths late next year on December 21st, something they do about every 20 years. Mars is in the morning sky and will rise in the east at 5:51 a.m. It’s not very bright because it’s 236 million miles (380 million km)

away

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

Addendum

Evening Planets

Jupiter, Saturn and the thin crescent Moon shown twice its actual size tonight, October 30 at 7:30 p.m. Created using Stellarium.

Binocular Moon

The thin crescent Moon with earthshine as it might appear in binoculars or a small telescope tonight at 7:30 p.m. October 30, 2019. Created using Stellarium.

Mars in the morning

Mars in the morning at 7:30 a.m. October 31, 2019. Created using Stellarium.

Telescopic Planets

Telescopic views of Jupiter and Saturn with the same magnification at 7:30 p.m. tonight October 30, 2019. Created using Cartes du Ciel (Sky Charts).

Planets and the Moon on a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on October 30, 2019. The night ends on the left with sunrise on the 31st. Click on the image to enlarge. Created using my LookingUp program.

10/29/2019 – Ephemeris – Finding the Pleiades or Seven Sisters

October 29, 2019 Comments off

Ephemeris for Tuesday, October 29th. Today the Sun will be up for 10 hours and 19 minutes, setting at 6:36, and it will rise tomorrow at 8:17. The Moon, 2 days past new, will set at 7:57 this evening.

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. When I was nearsighted, though corrected, I never had been able to see more than a few stars and a bit of fuzz. However with binoculars, even I can see over a hundred stars appear along with the dipper shape of the brightest. The fuzz I saw was unresolved stars, but in photographs the Pleiades actually contain wisps of the gas they are passing through currently. In Greek mythology the sisters were daughters of the god Atlas.

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

Addendum

Pleiades finder animation

Finding the Pleiades animation for 9 p.m. October 29, 2019. The Pleiades is surrounded by constellations I’ve described earlier this year and one yet to be described, Taurus the bull of which the cluster is a part.  The V of stars near the horizon is Taurus’ head and is another star cluster, the Hyades, the half sisters to the Pleiades. Created using Stellarium and GIMP.

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

The Pleiades, about what you’d see in binoculars, though not as brilliant.  One of my old photographs.  With my 11 inch f/4.5 Dobsonian using a 40mm eyepiece that gives a field of view that encompasses the Pleiades, all I can say is Wow!

Greek Pleiades

The Greek Pleiades a painting by Elihu Vedder in the Metropolitan Museum of Art, New York City. Public Domain.

10/28/2019 – Ephemeris – The constellations of Triangulum and Aries the ram

October 28, 2019 Comments off

Ephemeris for Monday, October 28th. Today the Sun will be up for 10 hours and 22 minutes, setting at 6:37, and it will rise tomorrow at 8:16. The Moon, 1 day past new, will set at 7:22 this evening.

High in the east-southeast at 9 p.m. can be seen the Great Square of Pegasus. From the top left star of the square diverge two curved lines of stars that is Andromeda the chained princess. Just below and left of Andromeda is a slender triangle of stars, none particularly bright. It has a name you can easily see in the stars, Triangulum, the triangle. Early Christians saw it as the Mitre of Saint Peter or the Trinity. Another small constellation seen below Triangulum is the much better known constellation Aries the ram, a small hockey stick of a constellation, not that hard to spot. It is the first constellation of the Zodiac, where the Sun is supposed to enter on the first day of spring. Due to the wobble of the Earth’s axis, that honor is now given to Pisces.

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

Addendum

Cetus, Triangulum, Aries and surrounding constellations on November 8, 2012 at 9 p.m. Created using Stellarium.

Cetus, Triangulum, Aries and surrounding constellations. Created using Stellarium.

Aries the ram

Aries the ram animated finder chart. Created using Stellarium and GIMP.

10/25/2019 – Ephemeris – Finding Pisces the fish

October 25, 2019 Comments off

Ephemeris for Friday, October 25th. 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, 2 days before new, will rise at 6:00 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 12 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 that is seen in the stars. The right or western end of Pisces is the asterism, or informal constellation, of the Circlet. It’s the loop of 5 stars, the rope around the tail of one of the two fish.

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

Addendum

Pisces finder animation

Pisces finder animation for 9 p.m. tonight October 25, 2019. Created using Stellarium and GIMP.

10/24/2019 – Ephemeris – Let’s find Aquarius

October 24, 2019 Comments off

Ephemeris for Thursday, 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, half way from last quarter to new, will rise at 4:41 tomorrow morning.

One of the constellations of the zodiac is in the southeastern sky at 8 in the evening. It’s the constellation of Aquarius the water bearer. The image that is supposed to be depicted in the stars is that of a fellow spilling a stone jar of water. Aquarius is fairly hard to spot because it is made of faint stars. One part of him, though, is easy to spot. That is the Water Jar, an asterism or informal constellation. It is a distinctive small nearly equilateral triangle of stars with another star in the center. Stars extending to the right from the water jar are the yoke he’s holding the water jar with. The Water jar is just below the top of the head of the upside down Pegasus the flying horse. The water is flowing down a vertical line of stars.

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

Addendum

Aquarius finder animation

Aquarius finder animation for tonight at 8 p.m. October 24, 2019. Created using Stellarium and GIMP.

10/23/2019 – Ephemeris – Our weekly look at the bright planets

October 23, 2019 Comments off

Ephemeris for Wednesday, October 23rd. Today the Sun will be up for 10 hours and 36 minutes, setting at 6:45, and it will rise tomorrow at 8:09. The Moon, 2 days past last quarter, will rise at 3:24 tomorrow morning.

Let’s look at the bright planets for this week. Venus and Mercury are too close to the Sun to be seen. They are on the evening or east side of the Sun. Bright Jupiter will be low in the southwestern sky as it gets dark. It will set at 9:23 p.m. Jupiter is moving at nearly its fastest to the east now and next year will be where Saturn is now. Saturn, the ringed planet, will be in the south-southwestern sky in the evening, and will set at 11:06 p.m. Next year it will be a bit farther east. Jupiter is approaching Saturn in our sky. They will cross paths late next year on December 21st, something they do about every 20 years. Mars will rise in the east at 6:36 a.m.

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

Addendum

Evening planets

Saturn and JUpiter with the Teapot of Sagittarius in the southwest tonight at 8 p.m. October 23, 2019. Created with Stellarium.

Telescopic planets

Telescopic views of Jupiter and Saturn with the same magnification at 8 p.m. tonight October 23, 2019. Created using Cartes du Ciel (Sky Charts).

Morning planets

Mars and the Moon at 7 a.m. tomorrow October 24, 2019. At thi scale the program shows the Moon as a blob. Created using Stellarium.

Binocular Moon

The Moon as it might be seen in binoculars, including earth shine, at 7 a.m. tomorrow October 24, 2019. Created using Stellarium.

Planets and the Moon on a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on October 23, 2019. The night ends on the left with sunrise on the 24th. Click on the image to enlarge. Created using my LookingUp program.