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03/24/2017 – Ephemeris – Finding Leo

March 24, 2017 Leave a comment

Ephemeris for Friday, March 24th.  The Sun will rise at 7:37.  It’ll be up for 12 hours and 22 minutes, setting at 8:00.  The Moon, 3 days before new, will rise at 6:24 tomorrow morning.

At 10 p.m. the spring constellation of Leo the lion will be high in the east-southeast.  It can be found by locating the Big Dipper high in the northeast and imagining that a hole were drilled in the bowl to let the water leak out.  It would drip on the back of this giant cat.  The Lion is standing or lying facing westward.  His head and mane are seen in the stars as a backwards question mark.  This group of stars is also called the sickle.  The bright star Regulus is at the bottom, the dot at the bottom of the question mark.  A triangle of stars, to the left of Regulus, is the lion’s haunches.  Leo contains some nice galaxies visible in moderate sized telescopes.  The stars in Leo’s part of the sky are sparser than those in the winter sky.

Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Add info on Mercury in the evening sky.

Addendum

Leaky Dipper drips on Leo.

Leaky Big Dipper drips on Leo. Created using mu LookingUp program.

Ursa Major and Leo

Ursa Major with the Big Dipper in her hind end and Leo. Created using Stellarium and GIMP.

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

March 23, 2017 Leave a comment

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.

03/22/2017 – Ephemeris – Wednesday is bright planet day but we seem to be missing one of them

March 22, 2017 Leave a comment

Ephemeris for Wednesday, March 22nd.  The Sun will rise at 7:41.  It’ll be up for 12 hours and 16 minutes, setting at 7:57.  The Moon, 2 days past last quarter, will rise at 5:09 tomorrow morning.

It’s still dark enough to see the morning planets again during these Ephemeris play times.  But it won’t last.  Jupiter will be seen in the morning in the southwest above the star Spica.  It will rise tonight at 9:19 p.m. in the East.  Saturn can be glimpsed this morning above the Teapot figure of Sagittarius in the south.  It will rise tomorrow at 3 a.m. in the east-southeast.  The crescent Moon will be in the east-southeast.  In the evening sky tonight Venus is essentially gone, just 3 days from passing inferior conjunction, it might be seen to the upper right of the Sun’s setting point.  I once spotted it this close to conjunction in the bright twilight.  It will set at 8:35 p.m.  Mars is still hanging on, in the west, and will set at 11:11 p.m.

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

Addendum

Morning planets

Jupiter, Saturn and the crescent Moon at 7 a.m. this morning March 22, 2017. Created using Stellarium.

Venus 15 minutes after sunset

Venus at 15 minutes after sunset on a flat horizon 3 days before inferior conjunction from 45 degrees north latitude. Venus is seen at 3 degrees, 24 minutes above the horizon and practically invisible. Mercury is getting ready for its appearance in the west next week. We will visit it in more detail on Friday.  Created using Stellarium.

Jupiter rising

Jupiter rising and the constellations of winter and spring at 10 p.m. this evening March 22, 2017. Created using Stellarium.

Telescopic Jupiter

Jupiter and its moons at 7 a.m. and 10 p.m. today, March 22, 2017. orientation of Jupiter is as it appears on the sky at those times. Created using Cartes du Ciel (Sky Charts).

Saturn and its moons

Saturn and its moons at 7 a.m. March 22, 2017. It is shown at the same scale as Jupiter above. Created using Cartes du Ciel (Sky Charts).

Binocular Moon

The waning crescent Moon at 7 a.m. as it might be seen in binoculars. Created using Stellarium.

Planets and Moon at sunset and sunrise of a single night

Planets and the Moon at sunset and sunrise of a single night starting with sunset on the right on March 22, 2017. The night ends on the left with sunrise on March 23. Note that Venus is visible at both sunrise and sunset at least on these charts. Click on image to enlarge. Created using my LookingUp program.

03/21/2017 – Ephemeris – Let’s find Cancer the crab

March 21, 2017 Comments off

Ephemeris for Tuesday, March 21st.  The Sun will rise at 7:43.  It’ll be up for 12 hours and 13 minutes, setting at 7:56.  The Moon, 1 day past last quarter, will rise at 4:26 tomorrow morning.

At 10 this evening, the faint constellation, and member of the Zodiac, Cancer the crab is located in the south half way between the bright stars Castor and Pollux of the constellation Gemini, high in the south and the bright star Regulus in Leo the lion in the southeast.  Cancer is very dim, looking like an upside-down Y if it’s stars can be made out.  In the center of Cancer is a fuzzy spot to the unaided eye.  In binoculars or a low power telescope this fuzzy spot becomes a cluster of stars.  It is the Beehive cluster.  At 577 light years away, according to the latest measurements, it is one of the closest star clusters, but more distant than the Pleiades and Hyades the face of Taurus the bull off in the west.

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

Addendum

Cancer the Crab

Cancer the crab finder chart. Note the beehive cluster, also known to amateur astronomers as M44, along with other catalog names. Created using Stellarium and GIMP.

The Beehive

The Beehive star cluster, M44. Its ancient name was the Praesepe or manger when glimpsed by the naked eye. Created using Cartes du Ciel (Skycharts)

03/20/2017 – Ephemeris – Spring starts today!

March 20, 2017 Comments off

Ephemeris for Monday, March 20th.  The Sun will rise at 7:45.  It’ll be up for 12 hours and 10 minutes, setting at 7:55.  The Moon, at last quarter today, will rise at 3:39 tomorrow morning.

This morning, at 6:29 (10:29 UT) the sun crosses overhead at the earth’s equator as it appears to head north, starting for us the season of spring.  It’s the vernal equinox.  As you can tell from my intro, we’re already above 12 hours of daylight, and we’ll add another 3 plus hours of daylight before summer begins in three months.  We are already adding about 3 minutes a day of daylight to that goal now, the maximum rate.  With the Sun out longer and its ascension higher in the sky each day, it is rapidly adding energy to the northern hemisphere.  We don’t feel that immediately.  While the land rapidly absorbs heat, the oceans and lakes, especially the Great Lakes are a big heat sink, taking a very long time to warm up.

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

Addendum

This March equinox also is the beginning of autumn for folks south of the equator.

Earth near equinox

Image from the DISCOVR satellite in halo orbit at the Earth-Sun L1 point, nearly a million miles (1.6 million km) sunward of the Earth. as of March 17, 2017. As usual Michigan is covered by a cloud.  Credit NOAA/NASA.

03/19/2017 – Ephemeris Extra – Comet 41P/Tuttle-Giacobini-Kresak is within reach of binoculars and small telescopes

March 19, 2017 Comments off

UT

Comet 41P finder chart

Comet 41P finder chart for the next month, March 20 to April 19. It is expected to be brightest at magnitude 6.6 in early April. Comet positions and orientation in the northeast are for 11:30 p.m. on the date specified or 3:30 UT on the next date. Created using Cartes du Ciel (Sky Charts).  Click on the chart to enlarge.

Note above:  The tail symbol points to the direction of a tail.  However none of the photographs I’ve seen show a tail, so none will be visible visually.

This comet is known to have frequent outbursts where its brightness increases by many times.  If an outburst occurs in early April, the comet could become visible to the naked eye.   Original source material for this post comes from Seiichi Yoshida’s Weekly Information about Bright Comets web page.  The comet will pass less than 14 million miles (22 million km) from Earth on April 5th, only 8 days before it’s closest approach to the Sun, called perihelion.  From the finder chart one can see the comet will pass to the north of the Earth.

According to Gary Kronk’s Cometography.com web site the comet was discovered and lost three times.  It was first discovered in 1858 by Horace Tuttle, whose name was attached to at two well known comets that produce meteor showers.  It was unobserved for the next eight returns, which were expected every 5.42 years.  Michel Giacobini rediscovered it again in 1907.  Giacobini was the discoverer of Comet Giacobini-Zinner, another famous meteor shower producing comet.  It was lost again until Lubos Kresák rediscovered it in 1951 after seven more missed returns.

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.