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Posts Tagged ‘Regulus’

04/13/2018 – Ephemeris – Regulus, in Leo the lion, the “Little King” star.

April 13, 2018 Comments off

Ephemeris for Friday, April 13th. The Sun will rise at 7:01. It’ll be up for 13 hours and 23 minutes, setting at 8:25. The Moon, 2 days before new, will rise at 6:42 tomorrow morning.

The brightest star in the constellation Leo, which is high in the south these evenings is Regulus, whose name means “Little King”. It is appropriate due to its position in the heart of the king of beasts Leo the lion. Regulus is dead last in brightness of the 21 first magnitude stars, the brightest night-time stars. Even so, it is much brighter than the Sun. It is 79 light years away. The Sun would require a telescope to be spotted at that distance. Regulus appears to be a quadruple star system. The bright star itself is really two stars with a bright star orbited by a much dimmer star every 40 days. There are two dimmer stars much further out that share Regulus’ motion through space. There are an infinite variety of star system arrangements in the galaxy and beyond.

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

Addendum

Regulus in Leo the Lion

The naked eye stars of Leo, including Regulus at 10 p.m. April 13, 2018. Note that Algieba is a binary star that can be seen in small telescopes. The yellow line that passes Regulus is the ecliptic the apparent path of the Sun. The Moon and planets also hang out near that line. Created using Cartes du Ciel (Sky Charts).

Note:  The original scheduled topic for today was the announcement of a star party at the Sleeping Bear Dunes National Lakeshore tomorrow, April 14th.  It seems the weather gods have a different plan.  There’s a winter storm watch from late Friday night (tonight) to noon Sunday with 3-6 inches of slushy snow.

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03/05/2018 – Ephemeris – Spring is coming: Leo is rising

March 5, 2018 Comments off

Ephemeris for Monday, March 5th. The Sun will rise at 7:13. It’ll be up for 11 hours and 22 minutes, setting at 6:35. The Moon, half way from full to last quarter, will rise at 10:53 this evening.

The constellation Leo the lion is now rising in the east at 9 pm. It’s below and left of the Big Dipper higher up in the east-northeast. 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 is 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. Ancients physicians thought medicines were poison when the Sun was here also.

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

Addendum

The constellation Leo animation

The constellation Leo animation. Created using Stellarium and GIMP.

Algieba is a binary star, which should be able to be split with any good telescope.  The magnitude 2.4 and 3.6 components are separated by 4.6 arc seconds.  Binary stars are one type of object that benefit from using high power to resolve.  The stars are very close in temperature, so each appears a yellow-orange color offering no color contrast.

10/13/2017 – Ephemeris – The bright star Regulus dips behind the Moon Sunday morning

October 13, 2017 1 comment

Note:  The original program recorded for this day was erroneous in the timing and appearance of this event.  Occurring about an hour later than reported here.  The Interlochen personnel may or may not replace the original program with the one below.  Also those who downloaded the audio from ephemeris.bjmoler.org before late Thursday night may have downloaded the incorrect mp3.

Ephemeris for Friday, October 13th. The Sun will rise at 7:55 a.m.. It’ll be up for 11 hours and 5 minutes, setting at 7:00 p.m. The Moon, 1 day past last quarter, will rise at 2:08 tomorrow morning.

On Sunday morning the Moon will pass in front of, or occult the bright star Regulus, the brightest star in Leo the lion. This will happen as morning twilight starts. Regulus will disappear at the left edge of the crescent Moon at around 5:47 a.m. A telescope or binoculars may be needed to spot Regulus. Go out at least 5 or 10 minutes early to make sure you can spot the star. Regulus will reemerge at 6:25 at the 11 o’clock position on the dark part of the Moon. Earth shine on the night side of the Moon may be bright enough to see its dark edge. Observers west of us in the United States except the northern most states west of Minnesota will also get a view. Those in specific locations in the northern tier of states will get to see Regulus just graze the north edge of the Moon.

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

Addendum

Occultation start

Occultation of Regulus by the Moon disappearance at around 5:47 a.m. for northern Michigan. Created using Stellarium.

Occultation end

Occultation of Regulus by the Moon reappearance at around 6:25 a.m. for northern Michigan. Created using Stellarium.

Occultation Map

Map showing the locations where the occultation of Regulus will be visible. For the area bounded by heavy lines the occultation will occur at night. Click on image to enlarge. Credit: Occult4 by IOTA.

09/08/2017 – Ephemeris – Dance of the planets in the morning

September 8, 2017 1 comment

Ephemeris for Friday, September 8th. The Sun will rise at 7:13. It’ll be up for 12 hours and 52 minutes, setting at 8:05. The Moon, 2 days past full, will rise at 9:39 this evening.

In clear skies after 6:15 or so in the morning two planets and a star can be spotted below Venus in the east. This may take binoculars to spot. Brightest of the two highest stars will be the planet Mercury, which will reach its greatest elongation from the Sun next Tuesday. The star Regulus is a bit to the left of it, and dimmer. Hardest of all to spot will be Mars, below, left of them. On the 16th Mercury and Mars will be in a very close conjunction, about one fifth of the Moon’s diameter apart. Mars, now is very far away, and is as dim as a Big Dipper star, which though bright, fares poorly in twilight. Next July when Mars is close to us, it will be brighter than Jupiter. The positions of Mercury, Regulus and Mars will change rapidly in the next week or so.

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

Addendum

Dance of the morning planets

Dance of the morning planets Mercury, Mars, Venus with the star Regulus at 6:30 a.m. (about 45 minutes before sunrise) on the mornings of September 9 through 17, 2017. Created using Stellarium and GIMP.

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.

03/23/2017 – Ephemeris – a single headed Hydra

March 23, 2017 Comments off

Ephemeris for Thursday, March 23rd.  The Sun will rise at 7:39.  It’ll be up for 12 hours and 19 minutes, setting at 7:59.  The Moon, 3 days past last quarter, will rise at 5:48 tomorrow morning.

In the southern evening sky can be found the constellation of Hydra the water snake.  Unlike the mythical monster Hercules fought of the same name this Hydra has but one head, which is its most distinctive part.  At 9 p.m. look to the south.  The head of Hydra is located directly to the left of Procyon the bright star in Orion’s little dog Canis Minor, and to the right of the star Regulus in Leo.  Hydra’s head is a small distinctive group of 6 stars that make a loop and the snake’s slightly drooping head.  At that time the sinuous body of Hydra sinks below the horizon in the southeast.  As it gets later in the evening the rest of Hydra’s body will slither to just above the southeastern horizon below the planet Jupiter this year and the bright star Spica in the constellation of Virgo.

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

Addendum

Hydra

Finding Hydra animation for 9 p.m. March 23rd 2017. Created using Stellarium.  Click on image to enlarge.

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.