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02/13/2018 – Ephemeris – The Big Dipper as a pointer to other stars and constellations

March 13, 2018 Comments off

Ephemeris for Tuesday, March 13th. The Sun will rise at 7:58. It’ll be up for 11 hours and 47 minutes, setting at 7:46. The Moon, 4 days before new, will rise at 6:42 tomorrow morning.

With the Big Dipper up in the northeastern sky it is a sign that spring is coming. At 9 p.m. The Big Dipper can be used to find other stars and constellations. The Big Dipper’s most famous function is in locating Polaris the North Star. It’s a good way of finding directions at night. The altitude of Polaris, that is angle above the horizon, will give one’s approximate latitude north of the equator. Another constellation that can be found is Leo the lion. It is rising in the east in the evening, but it can also be found from the Big Dipper by imagining that a hole were drilled in the bottom of the bowl to let the water leak out. It would fall on Leo’s back. The Big Dipper can be used to find two more stars, but they have not yet risen.

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

Addendum

The Big Dipper

The Big Dipper points to Polaris, the, North Star, and to Leo the lion at 9 p.m., March 13th. In another hour the 4th brightest night-time star Arcturus will appear above the eastern horizon pointed to by the arc of the handle of the Big Dipper. We’ll revisit the Big Dipper next month when Arcturus and Spica will also be found by the use of the Big Dipper. Created using Stellarium and Libre Office.

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03/06/2018 – Ephemeris – The Moon will pass the morning planets for the rest of the week

March 6, 2018 Comments off

Ephemeris for Tuesday, March 6th. The Sun will rise at 7:11. It’ll be up for 11 hours and 25 minutes, setting at 6:37. The Moon, 3 days before last quarter, will rise at 11:57 this evening.

From tomorrow morning through the rest of the week the Moon will be passing above the morning planets one by one. Tomorrow morning the waning gibbous Moon will appear above and left of Jupiter the brightest of the morning planets in the south at 6 a.m. By Friday morning the then last quarter Moon will be approaching Mars and will be to the right and above the red planet. Saturday morning the then waning crescent Moon will appear above and right between Mars and Saturn. Sunday morning the waning crescent Moon will be left of Saturn. I love waning crescent Moons in morning twilight. In a couple of weeks, on the evening of the 19th to be exact the waxing crescent moon will pass Venus and Mercury.

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

Addendum

Moon and morning planets for the week

The Moon and morning planets at 6 a.m. each morning Wednesday through Sunday March 7-11, 2018. The Moon’s size has been doubled to show its phase. Note that due to Earth’s revolution of the Sun, that the sky will rotate about one degree westward per day. Click on the image to enlarge. Created using Stellarium and GIMP.

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.

02/27/2018 – Ephemeris – The bright spot on the Moon tonight

February 27, 2018 Comments off

Ephemeris for Tuesday, February 27th. The Sun will rise at 7:23. It’ll be up for 11 hours and 4 minutes, setting at 6:27. The Moon, 2 days before full, will set at 6:38 tomorrow morning.

The moon tonight is bright. The sunrise line or terminator on the moon is crossing the large gray plain called Oceanus Procellarum, the largest of the moon’s seas. These seas were figments of the first telescopic observers imagination. They are really huge impact basins into which interior lava flowed. On the upper left edge of the moon near the terminator is a bright spot on the moon visible in binoculars. In a telescope it is a crater called Aristarchus. It is a fairly new crater, probably less than a billion years old. As a rule the brighter the crater the newer it is. Aristarchus is the brightest spot on the moon. Over the years visual astronomers have seen hazes and bright spots from time to time in and near Aristarchus.

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

Addendum

The Moon and Aristarchus

The Moon tonight at 9 p.m. February 27, 2018. Created using Virtual Moon Atlas.

Aristarchus close up

The crater Aristarchus. Credit: Lunar and Planetary Institute.

02/06/2018 – Ephemeris – Monoceros the Unicorn

February 6, 2018 Comments off

Ephemeris for Tuesday, February 6th. The Sun will rise at 7:55. It’ll be up for 10 hours and 2 minutes, setting at 5:58. The Moon, 1 day before last quarter, will rise at 1:09 tomorrow morning.

Among all the constellations in the sky of animals real and mythical, there is also a unicorn. It’s called Monoceros, and inhabits the southeastern sky at 9 p.m. bounded by Orion on the right, Canis Major, the great dog below and Canis Minor, the little dog to the left. Unfortunately for observers without optical aid Monoceros, though large, is devoid of any but the faintest stars. Maybe that’s why no one sees unicorns anymore. It has many faint stars because the Milky Way runs through it. To the telescope it is a feast of faint nebulae or clouds of gas and dust, the birth place of stars, including the red rose of the Rosette Nebula, and the strange and tiny Hubble’s Variable Nebula. It also contains beautiful telescopic triple star system, Beta (β) Monocerotis.

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

Addendum

Monoceros

Monoceros finder chart animation. Created using Stellarium and GIMP.

Rosette Nebula

Rosette Nebula in the infrared from the Spitzer Space Telescope. Credit: NASA/JPL/Caltech

Hubble's Variable Nebula

Hubble’s Variable Nebula photographed appropriately enough by the Hubble Space Telescope. Credit: NASA/ESA and The Hubble Heritage Team (AURA/STScI).

Monoceros DSO finder chart

Looking at some faint objects in Monoceros. NGC 2239 is the star cluster in the center of the Rosette Nebula. The nebula itself is extremely faint. It shows in photographs, but I’ve never seen it visually. The green circle shows Beta Monocerotis, the triple star. All these stars are extremely blue-white hot. Created using Cartes du Ciel (Sky Charts).

Also in the chart above is the semicircular Barnard’s Loop, a supernova remnant a great long exposure photography target.

 

01/31/2018 – Ephemeris – Lunar Eclipse happening now* and the bright planets for this week

January 31, 2018 Comments off

* The Ephemeris radio program run at 6:19 a.m. and 7 a.m. EST will run during the lunar eclipse.

Ephemeris for Wednesday, January 31st. The Sun will rise at 8:02. It’ll be up for 9 hours and 47 minutes, setting at 5:50. The Moon, at full today, will rise at 6:15 this evening.

We have a lunar eclipse in progress this morning. Before the partial phase starts the Moon will have a dusky appearance because the Moon will be in the Earth’s outer penumbra shadow.  The partial phase starts at 6:48 a.m. (11:48 UT), when the upper left part of the Moon will enter the Earth’s inner shadow, called the umbra. The Moon will be fully immersed in the shadow beginning at 7:51 a.m. (12:51 UT). It will probably disappear by then because the Sun will rise just after 8 a.m. and the Moon will set, at least in the Interlochen/Traverse City area at, 8:04.

Venus is our evening planet, but too close to the Sun to spot. At 7 a.m. Jupiter and Mars below left of it are in the south while Saturn is low in the southeast. Tomorrow morning Jupiter will rise at 2:20 a.m., Mars will follow at 3:25. Last of all Saturn will rise at 5:50 a.m.

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

Addendum

Partial eclipsed Moon

The partially eclipsed Moon at 7:40 a.m. January 31, 2018 from Traverse City, MI as simulated by Stellarium.

For more on the eclipse see yesterday’s post:  https://bobmoler.wordpress.com/2018/01/30/01-30-2018-ephemeris-looking-for-tomorrows-lunar-eclipse/.

On to the planets

Morning planets and the Eclipsed Moon

Morning planets and the partially eclipsed moon at 7 a.m. this morning, January 31, 2018. Click on the image to enlarge. Created using Stellarium.

Jupiter and moons

Jupiter and its moons at 7 a.m. this morning January 31, 2018. Created using Cartes du Ciel (Sky Charts).

Saturn and moons

Saturn and its brighter moons at 7 a.m. this morning January 31, 2018. Created using Cartes du Ciel (Sky Charts).

Planets at sunset and sunrise of a single night

Planets at sunset and sunrise of a single night starting with sunset on the right on January 31, 2018. The night ends on the left with sunrise on February 1st. Click on the image to enlarge. Created using my LookingUp program.

01/12/2018 – Ephemeris – A look at Gemini the very unusual twins

January 12, 2018 1 comment

Ephemeris for Friday, January 12th. The Sun will rise at 8:18. It’ll be up for 9 hours and 6 minutes, setting at 5:24. The Moon, half way from last quarter to new, will rise at 5:16 tomorrow morning.

The constellation Gemini, the Twins is visible half way up the sky in the east at 9 p.m. The namesake stars of the two lads will be on the upper left edge of the constellation, nearly vertically aligned. Castor is above, while Pollux, a slightly brighter star is below it. Lines of stars from Castor and Pollux to the right delineate the lads. In Greek mythology Castor and Pollux were twins, and half brothers, Castor was fathered by a mere mortal, while Pollux was fathered by Zeus in the famous Leda and the swan affair. The brothers, however were inseparable, and when Castor was killed during the quest for the Golden Fleece, Pollux pleaded with Zeus to let him die also. Zeus granted his wish, so they both appear in the sky together forever.

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

Addendum

Gemini

Gemini as it should appear at 9 p.m., January 12, 2018. Created using Stellarium.

Gemini with Castor and Pollux

Gemini with Castor and Pollux. A closeup with a different way to link the stars with constellation art.  Created with Stellarium.