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12/22/2017 – Ephemeris – The joining of a god and goddess, a second possibility of the Star of Bethlehem

December 22, 2017 1 comment

Ephemeris for Friday, December 22nd. The Sun will rise at 8:16. It’ll be up for 8 hours and 48 minutes, setting at 5:05. The Moon, half way from new to first quarter, will set at 9:21 this evening.

On Tuesday I talked about what I said was one of two possible physical explanations for the Star of Bethlehem. Here is the second. On August 13th of 3 BC Jupiter and Venus briefly merged in the pre-dawn skies against the constellation of Leo the lion. A month later Jupiter was in conjunction with Regulus the bright star in Leo, the little king star. Then 9 months later, after sunset on June 16th of 2 BC the two planets again joined as one in Leo. The king of the planets twice mating with Venus as Ishtar, the Babylonian goddess of fertility, against the constellation of the lion signifying Judah in Genesis? One might find meaning in all that, especially the Magi, who were Zoroastrian astrologer-priests from Persia.

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

Addendum

Jupiter-Venus conjunction of August 3, 3 BC.

Animation of the Jupiter-Venus conjunction of August 13, 3 BC. in the morning twilight. Created using Stellarium.

June of 2 BC just after sunset Jupiter and Venus again cross paths.

June 16, 2 BC just after sunset Jupiter and Venus again cross paths, at one point too close to be separated with the naked eye. Created using Stellarium.

 

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03/17/2017 – Ephemeris – When Ireland had the largest telescope in the world

March 17, 2017 Comments off

Ephemeris for St. Patrick’s Day, Friday, March 17th.  The Sun will rise at 7:50.  It’ll be up for 12 hours even, setting at 7:51.  The Moon, 3 days before last quarter, will rise at 1:01 tomorrow morning.

In the 19th century Ireland laid claim to having the largest telescope in the world.  It was a reflecting telescope with a mirror diameter of 72 inches.  It was built by William Parsons the Third Earl of Rosse.  The base of the telescope tube rested in a pit between two massive walls and could only look in a north-south direction.  It saw first usage in 1847.  The telescope was called the Leviathan of Parsonstown, and was in use until 1890.  Mirrors in those days was made of a silvery alloy called speculum.  Two mirrors were used alternately because speculum tarnished.  The mirror not in use would have to be re-polished and swapped in from time to time.  It was the largest telescope until the 100 inch at Mt. Wilson was put in service in 1917.

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

Addendum

Leviathan of Parsonstown

The 72 inch Leviathan of Parsonstown. source: http://www.klima-luft.de/steinicke/ngcic/persons/rosse3.htm

M51 drawing

A drawing of the Whirlpool Galaxy, M51 (NGC 5194 & 5195) by Lord Rosse with the 72 inch telescope. Public Domain.

M51 photo

The Whirlpool Galaxy, M51. Credit Scott Anttila.

The Whirlpool Galaxy is the only galaxy that I’ve actually visually seen spiral arms on.  It was seen using a Celestron 14″ telescope at Northwestern Michigan’s Joseph H. Rogers Observatory.  That was a looong time ago.

02/13/2017 – Ephemeris – The brightest night-time star has a tiny stellar companion

February 13, 2017 Comments off

Ephemeris for Monday, February 13th.  The Sun will rise at 7:45.  It’ll be up for 10 hours and 23 minutes, setting at 6:08.  The Moon, 3 days past full, will rise at 9:16 this evening.

Sirius is the brightest night-time star and is located in the south at 9 p.m. below and a bit left of Orion the Hunter.  We’ve visited Sirius last week.  But there is another star in the Sirius system that is practically invisible due to Sirius’ dazzling glare. It’s Sirius B, nicknamed the Pup, alluding to Sirius’ Dog Star title.  The tiny star was suspected as far back as 1834 due to Sirius’ wavy path in the sky against the more distant stars.  Sirius is only 8 light years away.  Sirius A and the Pup have 50 year orbits of each other.  The star was first seen by Alvan Clark in 1862 while testing a new telescope.  The Pup was the first of a new class of stars to be discovered, white dwarfs.  The Pup is about the size of the Earth, with the mass of our Sun; its out of fuel and slowly collapsing.

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

Addendum

Sirius' path

Sirius A & B’s path in the sky showing the wobble that betrayed the Pup’s presence. Credit Mike Guidry, University of Tennessee.

Sirius A and B

Sirius A and B (near the diffraction spike to the lower left), A Hubble Space Telescope photograph. Credit NASA, ESA.

Orion's Belt points to Sirius

Orion’s Belt points to Sirius. Created using Stellarium.

02/07/2017 – Ephemeris – Sirius: an important star in history

February 7, 2017 Comments off

Ephemeris for Tuesday, February 7th.  The Sun will rise at 7:53.  It’ll be up for 10 hours and 6 minutes, setting at 6:00.  The Moon, 3 days before full, will set at 5:53 tomorrow morning.

The brightest star-like object in the evening sky is Sirius, also known as the Dog Star.  It also is the brightest night-time star in our skies period.  Tonight at 9 p.m. it’s located in the southeastern sky.  The Dog Star name comes from its position at the heart of the constellation Canis Major, the great dog of Orion the hunter.  The three stars of Orion’s belt tilt to the southeast and point to Sirius.  The name Sirius means ‘Dazzling One’, a reference to its great brilliance and twinkling.  Its Egyptian name was Sothis, and its appearance in the dawn skies in late June signaled the flooding of the Nile, and the beginning of the Egyptian agricultural year.  Sirius owes much of its brightness to the fact that it lies quite close to us, only about 8 light years away.

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

Addendum

Heliacal rising of Sirius

A simulation of the heliacal rising of Sothis (Sirius) with the Egyptian Pyramids circa 2000 BC.  Note that Sirius is just visible to the right of the nearest Pyramid. Created using Stellarium and GIMP.

A heliacal rising is the first appearance of a star or planet in the morning after disappearing weeks or months before in the evening twilight.

12/29/2016 – Ephemeris – Astronomical milestones of 2016

December 29, 2016 Comments off

Ephemeris for Thursday, December 29th.  The Sun will rise at 8:19.  It’ll be up for 8 hours and 50 minutes, setting at 5:10.  The Moon is new today, and won’t be visible.

Looking back at 2016 the biggest astronomical news was the detection of gravitational waves coming from two separate collisions of black holes far beyond our Milky Way galaxy.  The two detectors in Washington state and in Louisiana recorded these events in September and December 2015, but the first announcement was made in February this year after the signals were cleaned up and studied.  The year saw the end of the European Space Agency’s Rosetta Mission to the comet we’ve come to call 67P after orbiting it for over two years.  The Opportunity and Curiosity rovers continued their exploration of Mars along with a fleet of satellites.  On a sad note, we lost pioneering Mercury astronaut John Glenn at the age of 95.

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

Addendum

Gravitational Waves Detected

The chirp heard ’round the world and indeed the universe. Credit: LIGO/Abbot et al. 2016. Hat tip: Phil Plait, the Bad Astronomer.

Rosetta, Final orbit

Rosetta, Final orbit. Credit & copyright European Space Agency (ESA)

 

12/23/2016 – Ephemeris – Another possible set of events that could have been the Star of Bethlehem

December 23, 2016 Comments off

Ephemeris for Friday, December 23rd.  The Sun will rise at 8:18.  It’ll be up for 8 hours and 48 minutes, setting at 5:06.  The Moon, 3 days past last quarter, will rise at 3:43 tomorrow morning.

The brilliant planet Venus is out evening star now, and one could say that’s its our Christmas Star.  And perhaps it was, or was part of the Star of Bethlehem.  Back in August of  3 BC the planet Jupiter and Venus appeared to come very close to one another.  The term for such an apparent close approach is called a conjunction.  Astrologers make a big deal out of such a chance alignment.   It’s like a trick photo of someone in the foreground appearing to hold up or leaning on a more distant object.   Anyway, 10 months later in June of 2 BC Jupiter again appeared to join Venus, this time so close they could not be separated by the human eye.  This all occurred against the constellation of Leo the lion which in Genesis is the symbol of Judah.

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

Addendum

Venus and Mars photograph

Venus and Mars in the twilight last night at 6 p.m., December 22, 2016. Photograph by Bob Moler.  Click on the image to enlarge.

I have more information on this set of conjunctions in my December 2 post announcing my program on the Star of Bethlehem:  https://bobmoler.wordpress.com/2016/12/02/12022016-ephemeris-my-talk-about-the-star-of-bethlehem-is-tonight/

 

12/22/2016 – Ephemeris – Could Jupiter and Saturn have combined to be the Star of Bethlehem?

December 22, 2016 Comments off

Ephemeris for Thursday, December 22nd.  The Sun will rise at 8:17.  It’ll be up for 8 hours and 48 minutes, setting at 5:05.  The Moon, 2 days past last quarter, will rise at 2:45 tomorrow morning.

This morning the planet Jupiter is seen right below the waning crescent Moon.  It reminds me of one of the possible answers to the questions to what the Star of Bethlehem was.  Back in 7 BC Jupiter passed Saturn three times in that year.  This is a reasonably rare occurrence especially against a particular constellation, which in this case was Pisces the fish, which would occur every 800 plus years.  Early in the run of this program there was another so-called triple conjunction of Jupiter and Saturn.  This time it was against the constellation of Virgo the virgin in 1980 and 81.  Jupiter passes Saturn every 20 years, but only when it does so when they are opposite the Sun in the sky is there a chance for a triple conjunction.  Tomorrow I’ll look at two really close conjunctions of Jupiter and Venus that also could have been seen by the Magi as the Star of Bethlehem.

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

Addendum

Jupiter and the Moon

Jupiter and the Moon at 7 a.m. this morning, December 22, 2016. Created using Stellarium.

Jupiter-Saturn Triple Conjunction

Jupiter and Saturn pass each other three times from May to December in 7 BC. Created using Cartes du Ciel (Sky Charts) and GIMP.  Click image to enlarge.