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Posts Tagged ‘Spica’

05/15/2017 – Ephemeris – A look at the constellation of Virgo the virgin

May 15, 2017 1 comment

Ephemeris for Monday, May 15th.  Today the Sun will be up for 14 hours and 49 minutes, setting at 9:03, and it will rise tomorrow at 6:13.  The Moon, 3 days before last quarter, will rise at 1:03 tomorrow morning.

Tonight at 10 p.m. in the south-southeast, is the constellation and member of the of the zodiac: Virgo the virgin.  Now Jupiter is seen against the constellation appearing above and right of its brightest star, Spica.  Virgo is a large constellation of a reclining woman holding a stalk of wheat.  Spica, is the head of that spike of wheat; and as such it ruled over the harvest in two of Virgo’s guises as the goddesses Persephone and Ceres.  Virgo is also identified as Astraea the goddess of justice.  The constellation of Libra, the scales, which she is associated with, is found just east of her low in the east-southeast.  Early Christians who sought to de-paganize the heavens saw Virgo as the Virgin Mary.  Virgo is the host to a grand cluster of galaxies.

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

Addendum

Virgo finder chart

Animated Virgo finder chart for 11 p.m., May 15, 2017. Created using Stellarium and GIMP.

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.

03.14/2017 – Ephemeris – It’s Pi Day!

March 14, 2017 Comments off

Ephemeris for Pi Day 3.14, Tuesday, March 14th.  The Sun will rise at 7:56.  It’ll be up for 11 hours and 51 minutes, setting at 7:47.  The Moon, 2 days past full, will rise at 10:04 this evening.

Welcome to Pi Day.  I had some NASA inspired links posted on this blog this past Sunday for your enjoyment.  Also simply do an Internet search for Pi Day and lots of fun information and activities will be listed.  I remember an exercise in high school calculating pi with an inscribed polygon in a circle of ever increasing numbers of sides.  Somewhere in there I messed up and came out with an answer that didn’t quite get there.  This was in the years B.C. that is Before Calculators.  Speaking of round things, Jupiter will rise this evening followed by the Moon and the star Spica in the east.  They will all be up by 10:30.  Jupiter is not yet an evening planet, since it is not up by sunset.  It’s still seen in the morning sky.

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

Addenda

Had I known in the tenth grade this strategy to calculate pi, I could have saved myself a lot of grief.  Simply google calculate pi with toothpicks.  One of the hits was this from Science Friday:  https://sciencefriday.com/articles/estimate-pi-by-dropping-sticks/*.  Basically it’s by dropping lots of toothpicks on a piece of paper with parallel lines spaced the length of the toothpicks apart.  The total number of toothpicks dropped times two divided by the number of toothpicks that cross a line will approximate pi.  The more drops, the closer to pi one gets.

  • In the formula in the link, if the length of the toothpicks equals the distance between the lines, those terms drop out of the formula.

Grouping of Jupiter, the Moon and the star Spica

Jupiter, the Moon and the star Spica

Jupiter, the Moon and the star Spica at 11 p.m. March 14, 2016. Since the Moon moves eastward about its diameter an hour. So observers east or west of here will see the Moon in a different position in relation to these other two bodies. Created using Stellarium.

06/09/2016 – Ephemeris – Waiting for the first stars to appear

June 9, 2016 Comments off

Ephemeris for Thursday, June 9th.  Today the Sun will be up for 15 hours and 30 minutes, setting at 9:27, and it will rise tomorrow at 5:56.  The Moon, 3 days before first quarter, will set at 12:59 tomorrow morning.

Lets look at the first stars and planets to appear tonight as it gets dark.  The first object to appear will be the fat crescent Moon in the southwest.  The planet Jupiter will be the next to appear after sunset left and above the Moon.  Mars, low in the southeast will appear reddish, shortly thereafter.  Looking very high in the southeast, the fourth brightest nighttime star will appear.  This will be Arcturus with an orange hue.  Saturn should appear to the left and below Mars.  Soon other stars will appear including the Big Dipper overhead.  Other bright stars will appear, the summer star Vega low in the northeast. Regulus between Jupiter and the Moon and Spica between Jupiter and Mars.

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

Addendum

The first stars and planets to appear after sunset

The sky at about 10 p.m. or a little later, watching the first stars and planets appear. Created using Stellarium. If viewing using Firefox right-click on the image and select View Image to enlarge.

05/24/2016 – Ephemeris – Follow the spike to Spica

May 24, 2016 Comments off

Ephemeris for Tuesday, May 24th.  Today the Sun will be up for 15 hours and 9 minutes, setting at 9:14, and will rise tomorrow at 6:04.  The Moon, 3 days past full, will rise at 11:35 this evening.

Just about due south at 11 p.m. is the bright star Spica which can be found from all the way back overhead to the Big Dipper.  Follow the arc of the handle of the Big Dipper to the bright star Arcturus high in the south, southeast.  Then straighten the curve of the arc to a straight spike which points to Spica.  Arcturus is much brighter than Spica and has an orange tint to Spica’s bluish hue.  In fact Spica is the bluest of the 21 first magnitude stars.  That means that it is hot.  Actually Spica is really two blue stars orbiting each other in 4 days.  Spica is 250 light years away, which is reasonably close.  Spica was an important star to the ancients.  One temple was built, and aligned to its setting point.

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

Addendum

Spike to Spica

The evening sky to the south. All the finder stars are there, so follow the arc of the Big Dipper’s handle to Arcturus. Straighten it to a spike that points to Spica. Created using Stellarium.

07/09/2015 – Ephemeris – The first stars to appear at night

July 9, 2015 Comments off

Ephemeris for Thursday, July 9th.  Today the Sun will be up for 15 hours and 23 minutes, setting at 9:29.   The Moon, 1 day past last quarter, will rise at 2:05 tomorrow morning, and tomorrow the Sun will rise at 6:07.

Let’s check out all the bright stars in the evening sky, as it gets dark tonight.  Low in the west are the planets Venus and Jupiter.  High in the west is the bright yellow-orange star Arcturus.  In the northwest is the Big Dipper,  whose curved handle points to Arcturus.  Straightening that curve to a spike will point to Spica a blue-white star low in the southwest.  The planet Saturn is located in the south.  Below and left of it is the red star Antares which usually twinkles merrily.  High in the east is the bright white star Vega.  To its lower right is Altair, and to its lower left the star Deneb.  Vega, Altair and Deneb make the Summer Triangle, whose rising in the east signals the coming of summer.

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

Addendum

I talked about seeing the first stars a month ago.  It seems that in holding star parties this time of year we spend a lot of time watching the first stars appear.  I wanted to discuss the Summer Triangle, but it wandered off to what you see above.  I’ll get there next week, I promise.

Firsat stars to appear

The first stars and planets to appear. See if you can located them from the text. Created using Stellarium for about 10 p.m., July 9, 2015.

05/11/2015 – Ephemeris – How to find the constellation Virgo

May 11, 2015 Comments off

Ephemeris for Monday, May 11th.  Today the Sun will be up for 14 hours and 39 minutes, setting at 8:59.   The Moon, at last quarter today, will rise at 3:08 tomorrow morning.  Tomorrow the Sun will rise at 6:18.

Friday I talked about that in spring we are looking out the thin side of our Milky Way galaxy’s disk.  One of the large constellations we see in the south at 11 p.m. can be found using the Big Dipper overhead, follow the arc of the handle to the bright star Arcturus, the straighten the arc to a spike to reach Spica, a bright blue-white star in the south.  Spica is the brightest star in the constellation Virgo the virgin.  She represents the goddess of the harvest,  Virgo is holding a sheaf of wheat in depictions of her, and Spica is placed at the head of the sheaf.  In the space between Spica and Leo the lion to her right is, a great cluster just below naked eye visibility.  The Virgo cluster of galaxies.

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

Addendum

Finding Virgo

Star hop from the Big Dipper through Arcturus to Spica and Virgo. Orientation for 11 p.m. on May 11, 2015. Created using Stellarium.