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Posts Tagged ‘Little Dipper’

08/28/2017 – Ephemeris – Polaris the North Star

August 28, 2017 1 comment

Ephemeris for Monday, August 28th. The Sun will rise at 7:00. It’ll be up for 13 hours and 25 minutes, setting at 8:25. The Moon, 1 day before first quarter, will set at 12:19 tomorrow morning.

The bright star Polaris is a very important star. It is also known as the North Star and the Pole Star. Its unique position is nearly directly at the zenith at the Earth’s north pole, making it a very important navigational star. It’s about 40 minutes of arc, or about one and a third Moon diameters away from the extension of the Earth’s axis into the sky. As a rule of thumb, it’s angular altitude above the northern horizon is approximately one’s latitude, and it stands about at the due north compass point. Polaris is found using the Big Dipper, using the two stars at the front of the dipper bowl to point to it. It’s located at the tip of the handle of the very dim Little Dipper, which this time of year in the evening appears to standing on its handle.

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

Addendum

Polaris Finder Chart

Polaris finder chart for 10 p.m., August 28th. Created using my LookingUp program

Rotation of the sky around Polaris

Animation of the rotation of the sky around Polaris on the night of August 28/29, 2017. Created using Stellarium and Filmora.

I’ve left the constellation lines off.  The Big Dipper is seen easily as is Cassiopeia’s “W” opposite it around the stationary Polaris.

 

 

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01/15/2016 – Ephemeris – The Comet Catalina is closest to the Earth this weekend

January 15, 2016 Comments off

Ephemeris for Friday, January 15th.  The Sun will rise at 8:16.  It’ll be up for 9 hours and 11 minutes, setting at 5:27.   The Moon, 1 day before first quarter, will set at 12:19 tomorrow morning.

Comet Catalina is near its brightest now that it’s closest to the Earth, or will be Sunday at about 67 million miles (108 million km), about three-quarters the distance to the Sun.  It is also circumpolar, staying up all night for the entire IPR listening area.  That’s not as big a deal as it sounds because the Moon won’t set till after midnight and it’s getting brighter as it moves to become full in a couple of weeks.  So the best views are still in the morning for the next week.  The comet can be spotted in binoculars as a fuzzy spot.  The comet is now nearest the star Mizar in the bend of the Big Dipper’s handle.  It’s slowly moving to split the distance between the Big and Little Dippers between now and the end of the month.  Good comet hunting!

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

Addendum

Comet Catalina

Comet Catalina closest weekend to the Earth. Comet positions are for 4 a.m. January 16 to 19, 2016. Created using Cartes du Ciel (Sky Charts).

Comet Catalina's Orbit

Comet C/2013 US10 (Catalina) at its closest approach to the Earth on January 17, 2016 of 0.725 AU, 67 million miles or 108 million kilometers. Credit NASA/JPL.

03/27/2015 – Ephemeris – The North Star, Polaris

March 27, 2015 Comments off

Ephemeris for Friday, March 27th.  The Sun will rise at 7:33.  It’ll be up for 12 hours and 30 minutes, setting at 8:03.   The Moon, at first quarter today, will set at 3:49 tomorrow morning.

Tonight we turn our eyes northward to Polaris, the North Star.  It is the closest bright star to the north pole of the sky.  It appears nearly stationary as all the other stars appear to revolve around it as the Earth rotates.  Some folks, think that Polaris is the brightest star in the sky.  It’s not.  It is a good solid second magnitude star, about the brightness of a Big Dipper star.  The Big Dipper can be used to point to it, by using the two stars at the front of the bowl.  Polaris is at the end of the handle of the Little Dipper.  The Little Dipper has four dim stars in its rather oddly bent handle and back of its bowl.  The two stars at the front of the bowl of the Little Dipper are Kochab and the dimmer Pherkad, which are also called the Guard Stars or the Guardians of the Pole.

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

Addendum

Polaris finder chart

How to find Polaris. The grid is the equatorial grid showing the proximity to the pole. Created using Stellarium.

06/26/2014 – Ephemeris – Draco the dragon is twisted around the pole of the sky

June 26, 2014 Comments off

Ephemeris for Thursday, June 26th.  Today the sun will be up for 15 hours and 32 minutes, setting at 9:31, the latest sunset.   The moon, 1 day before new, will rise at 6:32 tomorrow morning.  Tomorrow the sun will rise at 5:59.

High in the northern sky at 11 p.m. lies the twisted constellation, that of Draco the dragon.  This dragon is more like the snakelike Chinese dragon than the dinosaur like dragon of European legend.  I find it better to start at the tail of Draco, to trace him out in the stars.  Draco’s tail starts between the bowl of the Big Dipper and the Little Dipper.  The Dragon is seen in a line of stars that extends parallel to the handle of the Big Dipper before curving around the bowl of the Little Dipper then bends back toward the south.  The head of Draco is an odd box of stars near the bright star Vega, high in the east.  Though not made up of very bright stars, Draco has an easy shape to trace.

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

Addendum

Draco via Stellarium

Draco via Stellarium in approximately the same orientation as the Jamieson atlas below. You’s have to face southeast and bend over backward to see this orientation in the sky.

Draco

Draco the Dragon as drawn in Alexander Jamieson’s 1820 Celestial Atlas as printer in Men, Monsters and the Modern Universe by George Lovi and Wil Tirion, 1989, Willmann-Bell, Richmond, VA

09-24-2013 – Ephemeris – The dragon in the sky

September 24, 2013 Comments off

Ephemeris for Tuesday, September 24th.  The sun will rise at 7:32.  It’ll be up for 12 hours and 3 minutes, setting at 7:35.   The moon, 2 days before last quarter, will rise at 10:40 this evening.

High in the northern sky at 9 p.m. lies a twisted constellation, that of Draco the dragon.  This dragon is more like the snakelike Chinese dragon than the dinosaur like dragon of European legend.  At least that’s how I see it.  I find it better to start at the tail of Draco, to trace him out in the stars.  Draco’s tail starts between the bowl of the Big Dipper and the Little Dipper.  The Dragon is seen in a line of stars that extends parallel to the handle of the Big Dipper before curving around the bowl of the Little Dipper to the east then bends back toward the west.  The head of Draco is an odd box of stars near the bright star Vega, nearly overhead.  Though not made up of very bright stars, Draco has an easy shape to trace.

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

Addendum

Draco

Draco and neighboring constellations at 9 .m. September 24, 2013. Created using Stellarium. Constellation art by Johan Meuris.

06/18/2012 – Ephemeris – The Little Dipper

June 18, 2012 Comments off

Ephemeris for Monday, June 18th.  Today the sun will be up for 15 hours and 33 minutes, setting at 9:30.   The moon, 1 day before new, will rise at 6:03 tomorrow morning.  Tomorrow the sun will rise at 5:57.

11 p.m. is the best time now to spot the Little Dipper.  It is difficult to spot, being mush smaller and dimmer than the Big Dipper.  However it is the Big Dipper that points to it, by the two stars at the front of the bowl of the Big Dipper to point to the North Star Polaris, the star that doesn’t appear to move.  That is the tip of the handle of the Little Dipper.  The handle is seen in a curve of the stars upwards and a bit to the left to a small box of stars that is its bowl.  The two stars at the front of the bowl  are called the Guard Stars because they guard the pole.  The Little Dipper is not an official constellation, but is Ursa Minor the lesser bear.  To the Anishinabek native peoples of this area it represents a loon.

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

Addendum

Little Dipper (Ursa Minor) and the Big Dipper (Ursa Major).  Created using Stellarium.

Little Dipper (Ursa Minor) and the Big Dipper (Ursa Major). Created using Stellarium.