Archive

Posts Tagged ‘Big Dipper’

06/27/2017 – Ephemeris – Arcturus as a look at the Sun’s future

June 27, 2017 1 comment

Ephemeris for Tuesday, June 27th. Today the Sun will be up for 15 hours and 32 minutes, setting at 9:31, and it will rise tomorrow at 5:59. The Moon, 3 days before first quarter, will set at 12:18 tomorrow morning.

With the Moon brightening the night sky, let’s take a look at the star Arcturus, which with its pointer, the curve of the Big Dipper’s handle is slipping into the high western sky. Arcturus is the 4th brightest night time star, though some think the star Vega, high in the east is brighter. They are different colors because Arcturus is orange, while Vega is whiter than the Sun. Arcturus is a preview of what the Sun will become in four or five billion years from now. It is only 10% more massive than the Sun and is that much older than the Sun, so it is turning into its red giant stage, after running out of hydrogen to turn into helium in its core to produce energy. The helium is now compressing and heating to begin its reaction.

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

Addendum

Arcturus finder chart

Arcturus finder chart with the Big Dipper and Vega as guide posts. Created using Stellarium.

Here’s one of my prior posts about Arcturus, about its great space velocity:  https://bobmoler.wordpress.com/2016/04/26/04262016-ephemeris-arcturus-just-passing-through/

05/25/2017 – Ephemeris – Another look at Leo the lion

May 25, 2017 1 comment

Ephemeris for Ascension Thursday, Thursday, May 25th.  Today the Sun will be up for 15 hours and 9 minutes, setting at 9:14, and it will rise tomorrow at 6:04.  The Moon is new today, and won’t be visible.

The constellation Leo the lion is now high in the southwest at 10:30 pm.  It’s below the Big Dipper higher up near the zenith.  Leo is marked by two sets of easily recognizable stars.  The front of him is a backward question mark of stars, also known as the Sickle that mark his head and mane, along with the front part of his body.  Regulus is the star at the bottom of that backwards question mark.  It’s the Little King Star.  The hind end of him is a triangle of stars ending with another bright star, but not as bright as Regulus.  It’s Denebola which means Lion’s tail.  It was thought when the sun was in this constellation long ago that the lions were driven by the heat to quench their thirst in the Nile river.   Ancient physicians thought medicines were poison when the Sun was here too.

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

Addendum

Finding Leo the lion

Animation on how to find Leo the lion at 10:30 p.m., May 25, 2017. Created using Stellarium and GIMP.  Click on image to enlarge if necessary.

05/23/2017 – Ephemeris – The Big Dipper as seen in many lands

May 23, 2017 Comments off

Ephemeris for Tuesday, May 23rd.  Today the Sun will be up for 15 hours and 6 minutes, setting at 9:12, and it will rise tomorrow at 6:05.  The Moon, 2 days before new, will rise at 5:38 tomorrow morning.

The Big Dipper is overhead at 10 in the evening, it’s seven stars shining brightly. The Big Dipper is not an actual constellation, recognized internationally. It’s part, the hind part, of Ursa Major, the great bear. The Big Dipper is an asterism or informal constellation. It is a distinctly North American constellation. For fugitive slaves, fleeing the southern states in the days before the Civil War, the Drinking Gourd, as they called it, showed the direction north to freedom. In England the dipper stars become the Plough, or Charles’ Wain (Charlemagne’s Wagon), In France, known for culinary delights it was the saucepan, or the cleaver. So many cultures saw what was familiar to them in these seven bright stars.

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

Addendum

The many faces of the Big Dipper

The Big Dipper as I imagine it from some lands facing southwest and looking straight up. The X in the picture is the zenith point. We cycle through the stars only, the Big Dipper or the Saucepan, The Plough (plow in the U.S.), Charles Wain, and finally the Cleaver. Created using my LookingUp program.

Do you know any other asterisms or informal constellations assigned to these stars, add a comment.

 

05/22/2017 – Ephemeris – Why does the Great Bear have a long tail?

May 22, 2017 Comments off

Ephemeris for Monday, May 22nd.  Today the Sun will be up for 15 hours and 4 minutes, setting at 9:11, and it will rise tomorrow at 6:06.  The Moon, 3 days before new, will rise at 5:01 tomorrow morning.

The Great Bear, or Ursa Major as the Greeks, Romans and others saw it, has been handed down to us to this day.  We see the Great Bear as the Big Dipper overhead in the evening now, which is just his hind end, with a long very unbearlike tail.  The ancient Greek story goes that a god, not wishing to grab the end with the teeth, grabbed instead her stubby tail and in hurling her into the sky, and stretched the tail.  Native Americans who also saw a bear here, saw the three stars of the dipper handle as three hunters following the bear.  The local Anishinaabek people saw here instead the Fisher, a magical weasel-like animal who had a long tail naturally.  He brought summer to the Earth, and was killed for his efforts, but was placed in the sky to show us the seasons.

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

Addendum

The Great Bear and the Fisher

The Big Dipper/Great Bear/Fisher as seen by western and Anishinaabek people. Created using Stellarium and GIMP.

Western art is by Johan Meuris.

The source for the Ojibwe constellation art in Stellarium is from Ojibwe Sky Star Map Constellation Guide (An introduction to Ojibwe Star Knowledge) by Annette S. Lee, William Wilson, Jeffrey Tibbetts, and Carl Gawboy, ISBN 978-0-615-98678-4.  The illustrations are by Annette S. Lee and William Wilson.  There is also a poster sized star map available.  It should be available in book stores locally, or on Amazon.  I found my copy at Enerdyne in Suttons Bay.

My retelling of the Fisher or Fisher Star is here:  https://bobmoler.wordpress.com/2012/10/11/the-story-of-the-fisher-star/

04/17/2017 – Ephemeris – How to find the stars Arcturus and Spica from the Big Dipper

April 17, 2017 Comments off

Ephemeris for Monday, April 17th.  The Sun rises at 6:54.  It’ll be up for 13 hours and 35 minutes, setting at 8:30.  The Moon, 2 days before last quarter, will rise at 2:21 tomorrow morning.

The Big Dipper, now nearing the zenith at 10 p.m. points to several stars and constellations.  It’s handle points to two bright stars.  First we follow the arc of the handle to the bright orange star Arcturus, the 4th brightest night-time star.  The reason I say night-time is that the sun is a star also but by definition is not out at night.  The arc to Arcturus is a how to find Arcturus and a clue to its name.  Arcturus, midway up the sky in the east, lies at the base point of the kite shaped constellation of Boötes the herdsman.  From Arcturus, straighten out the arc to a spike and one soon arrives at Spica a blue-white star in Virgo the virgin, now low in the southeast.  It is below Jupiter this year.  Spica is also sometimes pronounced ‘Speeka’.

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

Addendum

Finding Arcturus and Spica

How to find the stars Arcturus and Spica from the Big Dipper in April 2017. Created using my LookingUp program.

03/24/2017 – Ephemeris – Finding Leo

March 24, 2017 Comments off

Ephemeris for Friday, March 24th.  The Sun will rise at 7:37.  It’ll be up for 12 hours and 22 minutes, setting at 8:00.  The Moon, 3 days before new, will rise at 6:24 tomorrow morning.

At 10 p.m. the spring constellation of Leo the lion will be high in the east-southeast.  It can be found by locating the Big Dipper high in the northeast and imagining that a hole were drilled in the bowl to let the water leak out.  It would drip on the back of this giant cat.  The Lion is standing or lying facing westward.  His head and mane are seen in the stars as a backwards question mark.  This group of stars is also called the sickle.  The bright star Regulus is at the bottom, the dot at the bottom of the question mark.  A triangle of stars, to the left of Regulus, is the lion’s haunches.  Leo contains some nice galaxies visible in moderate sized telescopes.  The stars in Leo’s part of the sky are sparser than those in the winter sky.

Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Add info on Mercury in the evening sky.

Addendum

Leaky Dipper drips on Leo.

Leaky Big Dipper drips on Leo. Created using mu LookingUp program.

Ursa Major and Leo

Ursa Major with the Big Dipper in her hind end and Leo. Created using Stellarium and GIMP.

02/20/2017 – Ephemeris – The spring constellations are rising

February 20, 2017 Comments off

Ephemeris for President’s Day, Monday, February 20th.  The Sun will rise at 7:34.  It’ll be up for 10 hours and 44 minutes, setting at 6:18.  The Moon, 2 days past last quarter, will rise at 3:59 tomorrow morning.

With spring only a month away, lets turn our eyes eastward in the evening to the rising spring stars.  In contrast to the brilliant stars of the winter skies still holding forth in the south, and running along the Milky Way overhead and to the northwest, the stars to the east are rather sparse and dull.  The only exception is the Big Dipper to the northeast.  The one bright star in the east is Regulus, whose rank as a first magnitude star is dead last in brightness.  It is in the heart of the constellation of Leo the lion, and as such has gained a great amount of fame.  Regulus is at the base of a backward question mark of stars that is informally known a the Sickle.  It is also the characteristic head and mane of a male lion.  A triangle of stars to the lower left are his back end ending with Leo’s second brightest star Denebola, literally “Lion’s Tail”.

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

Addendum

 

Comparison of winter stars vs. spring stars.

Comparison of winter stars vs. spring stars. Created using Stellarium.

The constellation Leo animation

The constellation Leo animation. Created using Stellarium and GIMP.