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Ephemeris: 02/20/2025 – Can you find the celestial unicorn?
This is Bob Moler with Ephemeris for Thursday, February 20th. Today the Sun will be up for 10 hours and 43 minutes, setting at 6:18, and it will rise tomorrow at 7:33. The Moon, at last quarter today, will rise at 3:06 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 8 p.m. mostly bounded by Orion on the right, Canis Major, the great dog below and Canis Minor, the little dog to the left and above. Unfortunately for observers without a telescope Monoceros, is devoid of any but the faintest stars. Maybe that’s why no one can find unicorns anymore. It has many faint stars because the Milky Way runs through it. For the astrophotographer it is a feast of star clusters and faint nebulae or clouds of gas and dust, the birthplace of stars, including the red rose of the Rosette Nebula. It also contains a beautiful telescopic triple star system, Beta (β) Monocerotis.
The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EST, UT – 5 hours). Times will be different for other locations.
Addendum
022/21/2020 – Ephemeris – The almost invisible unicorn
Ephemeris for Friday, February 21st. Today the Sun will be up for 10 hours and 44 minutes, setting at 6:19, and it will rise tomorrow at 7:32. The Moon, 2 days before new, will rise at 7:27 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 southern 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 contains no bright stars, but a wealth of wonders below naked eye visibility.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Monoceros the unicorn seen mostly inside the Winter Triangle of Betelgeuse, Sirius and Procyon. Note the star in the unicorn’s right hoof denoted with a funny B. That’s Beta Monocerotis,a triple star visible in small telescopes. Created using Stellarium with additions.
Rosette Nebula in the infrared from the Spitzer Space Telescope. Credit: NASA/JPL/Caltech
Hubble’s Variable Nebula photographed appropriately enough by the Hubble Space Telescope. Credit: NASA/ESA and The Hubble Heritage Team (AURA/STScI).
Telescopic Beta Monocerotis. William Hershel, discoverer of Uranus, said that it was “One of the most beautiful sights in the heavens.” Credit: F. Ringwald, Fresno State.
01/28/2019 – Ephemeris – The celestial unicorn
Ephemeris for Monday, January 28th. Today the Sun will be up for 9 hours and 39 minutes, setting at 5:45, and it will rise tomorrow at 8:05. The Moon, 1 day past last quarter, will rise at 2:52 tomorrow morning.
Within a triangle bounded by stars Betelgeuse in Orion, Sirius in Canis Major and Procyon in Canis Minor, called the Winter Triangle appears a nearly starless patch of sky to the naked eye. In here is the constellation Monoceros, the unicorn. 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 finder chart animation. Created using Stellarium and GIMP.
Rosette Nebula in the infrared from the Spitzer Space Telescope. Credit: NASA/JPL/Caltech
Hubble’s Variable Nebula photographed appropriately enough by the Hubble Space Telescope. Credit: NASA/ESA and The Hubble Heritage Team (AURA/STScI).
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).
Telescopic Beta Monocerotis. William Hershel, discoverer of Uranus, said that it was “One of the most beautiful sights in the heavens.” Credit: F. Ringwald, Fresno State.
02/06/2018 – Ephemeris – Monoceros the Unicorn
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 finder chart animation. Created using Stellarium and GIMP.
Rosette Nebula in the infrared from the Spitzer Space Telescope. Credit: NASA/JPL/Caltech
Hubble’s Variable Nebula photographed appropriately enough by the Hubble Space Telescope. Credit: NASA/ESA and The Hubble Heritage Team (AURA/STScI).
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.
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