10/31/2016 – Ephemeris – What’s a Halloween sky without the Ghoul Star

Ephemeris for Halloween, Monday, October 31st.  The Sun will rise at 8:20.  It’ll be up for 10 hours and 12 minutes, setting at 6:32.  The Moon, 1 day past new, will set at 7:28 this evening.

Not all the ghosts and goblins out tonight will be children.  One is out every night, because it’s a star.  Its name is Algol, from the Arabic for Ghoul Star or Demon Star.  The Chinese had a name for it that meant ‘piled up corpses’.  It’s the second brightest star in the constellation Perseus the hero, rising in the northeast this evening.  The star is located where artists have drawn the severed head of Medusa, whom he had slain.  Medusa was so ugly that she turned all who gazed upon her to stone.  Algol is her still glittering eye.  Astronomers finally found out what was wrong with Algol.  It does a slow 6 hour wink every 2 days 21 hours because it is two very close stars that eclipse each other in that period.  It did so this morning at 5:53 a.m.

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

Addendum

To run an app to calculate times for the minima of Algol click here:  http://www.skyandtelescope.com/observing/celestial-objects-to-watch/the-minima-of-algol/ courtesy of Sky and Telescope Magazine.

Perseus with Cassiopeia and Andromeda in the northeast at 8:30 p.m. on Halloween.  Created using Stellarium and GIMP.

Animation of an eclipsing binary star like Algol. Credit: Wikimedia Commons h/t Earth and Sky

 

 

 

10/28/2016 – Ephemeris – The Moon will hang by Jupiter this morning

Ephemeris for Friday, October 28th.  The Sun will rise at 8:16.  It’ll be up for 10 hours and 20 minutes, setting at 6:36.  The Moon, 2 days before new, rose this morning at 6:02 and will rise at 7:01 tomorrow morning.

This morning the planet Jupiter and the Moon will appear close together in the morning sky.  Jupiter rose at 6:03 a.m.  After that until twilight becomes too bright both will appear together with Jupiter to the right of the thin waning crescent Moon.  They passed each other at 4:18 (8:18 UT) this morning.  Jupiter will appear to move farther from the Sun in the coming months, more the Sun moving away from it caused by the Earth’s motion around the Sun.  Jupiter will enter the evening sky in April next year, passing in front of the zodiacal constellation of Virgo.  By then we will have lost Venus as our Evening Star, so Jupiter will have no competition when it arrives from the east.

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

Addendum

The Moon and Jupiter at 7 a.m. EDT (11:00 UT) this morning October 28, 2016. Stellarium and any other planetarium program cannot display the dynamic range of he sky. The sliver of the moon should be a lot brighter, including earthshine on its night side. I had to delete a star that was showing way too bright when it should be barely visible. Created using Stellarium and GIMP.

For observers in the UK and Europe the Moon will appear above Jupiter.  As a rule of thumb, the Moon moves its own diameter in an hour against the stars.  In the sky in the east just before sunrise the Moon will be moving down and to the left in relation to Jupiter.

10/27/2016 – Ephemeris – Finding the Great Andromeda Galaxy

Ephemeris for Thursday, October 27th.  The Sun will rise at 8:14.  It’ll be up for 10 hours and 23 minutes, setting at 6:37.  The Moon, 3 days before new, will rise at 6:02 tomorrow morning.

The closest large galaxy to our Milky Way galaxy is the Great Andromeda Galaxy seen in the eastern sky when it gets dark.  It is barely visible to the naked eye.  To locate it first find the Great Square of Pegasus high in the east, standing on one corner.  The left star of the square is the head of the constellation Andromeda.  Follow two stars to the left and a bit downward, then two stars straight up.  The galaxy is near that last star as a small smudge of light.  Binoculars are the best way to see it as a thin spindle of light.  A telescope can see only the bright nucleus of the galaxy, that spans 6 Moon diameters in photographs.  M31 is its first catalog designation and it is two and a half million light years away.

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

Addendum

Andromeda in the evening with the Great Andromeda Galaxy. Astronomers called it a nebula before the discovered it was a galaxy like the Milky Way.  Created using Stellarium.

The Great Andromeda Galaxy (M31) as seen in binoculars. Visually even in a telescope the hub of this galaxy is all that is seen. However it also can be seen with the naked eye. My photograph.

The Great Andromeda Galaxy (M31). Image taken by Scott Anttila.

10/26/2016 – Ephemeris – Bright planet count: 1 in the morning, 3 in the evening, 1 behind the Sun

Ephemeris for Wednesday, October 26th.  The Sun will rise at 8:13.  It’ll be up for 10 hours and 26 minutes, setting at 6:39.  The Moon, half way from last quarter to new, will rise at 5:03 tomorrow morning.

Low in the east this morning at 7 Jupiter can be glimpsed in the twilight.  Jupiter’s rose this morning at 6:09 a.m.  Venus, Saturn and Mars are in the evening sky. Venus is briefly visible after sunset, low in the west-southwest.  It will set at 8:16 p.m.  Venus is still moving a bit southward and will still be hugging the southwestern horizon for the next month or so, but it’s high enough to spot with a reasonably low horizon.  Saturn is above and left of Venus,  It will set at 8:44 p.m.  Mars can be seen in the darkened sky after Venus sets.  Mars is way out to the left of Saturn, above and left of the setting Teapot of Sagittarius at 9 p.m. in the southwest.  Mars will set at 11:08 p.m.  Mercury will pass behind the Sun tomorrow.

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

Addendum

The evening planets in twilight at 7:30 p.m. Venus and Mars are easily spotter, but Saturn is problematic. Created using Stellarium.

Jupiter and the Moon at 7 a.m. this morning, October 26, 2016. Created using Stellarium.

The Moon as it might appear in binoculars at 7 a.m. this morning, October 26, 2016. The Mood will also show a faint earthshine on its normally hidden light side to the right of the crescent. Created using Stellarium.

Planets and Moon at sunset and sunrise of a single night starting with sunset on the right on October 26, 2016. The night ends on the left with sunrise on October 27. If you are using Firefox right-click on the image and select View Image to enlarge the image. That goes for all the large images. Created using my LookingUp program.

10/25/2016 – Ephemeris – Venus is becoming more visible after sunset

Ephemeris for Tuesday, October 25th.  The Sun will rise at 8:12.  It’ll be up for 10 hours and 28 minutes, setting at 6:40.  The Moon, 3 days past last quarter, will rise at 4:02 tomorrow morning.

Venus is becoming quite visible low in the southwest after sunset as the Evening Star.  As such it is a beautiful addition to our autumn and winter skies.  As seen in telescopes it is a tiny gibbous disc, 79% illuminated by the sun.  It’s beauty is only cloud-top deep.  For a planet that appears to be nearly Earth’s twin at 95% the Earth’s size, it can be said to be Earth’s evil twin.  Its bright white cloud-tops aren’t made of water but sulfuric acid, and it gets worse the farther down you go.  The farther one goes down in Venus’ carbon dioxide atmosphere, the hotter and higher the atmospheric pressure gets.  At the surface the temperature is over 850 degrees Fahrenheit (460º C) and the atmospheric pressure is nearly 100 times that of Earth.  Venus’ surface temperature is actually hotter than Mercury the closest planet to the Sun, a hellish runaway greenhouse effect.

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

Addendum

 

Venus and the other evening planets at 7:30 p.m. Created using Stellarium.

Venus as it might appear in a telescope minus all the atmospheric effects of being close to the horizon. It is 13.6 ‘ in diameter. Created using Stellarium.

10/24/2016 – Ephemeris – Fomalhaut, the loneliest star in the sky

Ephemeris for Monday, October 24th.  The Sun will rise at 8:10.  It’ll be up for 10 hours and 31 minutes, setting at 6:42.  The Moon, 2 days past last quarter, will rise at 3:01 tomorrow morning.

There’s a bright star that appears for only seven and a half hours on autumn evenings.  It’s appearance, low in the south at 10 p.m., is a clear indication of the autumn season.  The star’s name is Fomalhaut, which means fish’s mouth.  That’s fitting because it’s in the constellation of Piscis Austrinus, the southern fish.  At our latitude it’s kind of the fish that got away, because Fomalhaut appears to be quite alone low in the sky.  The dimness of the constellation’s other stars and location close to the horizon make the faint stars hard to spot. The earth’s thick atmosphere near the horizon reduces their brightness by a factor of two or more, so Fomalhaut, one of the brightest stars in the sky, keeps a lonely vigil in the south.

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

Addendum

Aquarius and Fomalhaut as visualized by Stellarium. 

10/21/2016 – Ephemeris – Last star party of the year at Sleeping Bear Dunes

Ephemeris for Friday, October 21st.  The Sun will rise at 8:06.  It’ll be up for 10 hours and 40 minutes, setting at 6:47.  The Moon, 1 day before last quarter, will rise at 11:54 this evening.

Tonight if it’s clear the Grand Traverse Astronomical Society will join the rangers at the Sleeping Bear Dunes National Lakeshore for their 46th anniversary celebration with a star party at Stop number 3, the Dunes Overlook on the Pierce Stocking Scenic Drive, though park at Picnic Mountain, just before it.  The event will run from 8 to 10 p.m. featuring the wonders still visible among the northern summer wonders along with those appearing in the autumn skies, such as the Great Andromeda Galaxy and the famous Double Cluster.  To get a heads up on the status of the star party call 231-326-4700, extension. 5005, for a message after 4 p.m. if the weather looks doubtful.  Despite being October we’ve had pretty good luck with getting clear skies for this event.

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

Addendum

Star Party at the Dunes Overlook. Credit: Eileen Carlisle

10/20/2016 – Ephemeris – Perseus: Is it a hero or a chicken?

Ephemeris for Thursday, October 20th.  The Sun will rise at 8:05.  It’ll be up for 10 hours and 43 minutes, setting at 6:48.  The Moon, 2 days before last quarter, will rise at 10:54 this evening.

Positioned below the W shaped constellation of Cassiopeia half way up the sky in the northeast at 9 p.m. is the constellation of Perseus the hero of Greek myth who slew Medusa and rescued and married Andromeda represented in the constellation above and right of him.  Rather than a hero the star pattern seems to look like a chicken or perhaps Big Bird.  At least, that’s how I see it.  In the back of the chicken is its brightest star Mirfak (Mirphak).  Binoculars will show a beautiful group of stars near Mirfak just below unaided eye visibility called the Alpha Persei Association.  Tomorrow morning will see the peak of the Orionid meteor shower, though all but the brightest meteors will be overwhelmed by waning gibbous Moon.

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

Addendum

Perseus with Cassiopeia and Andromeda in the northeast at 9 p.m. October 20, 2016. Created using Stellarium and GIMP.

10/19/2016 – Ephemeris – Jupiter is in morning twilight, Venus in evening twilight

Ephemeris for Wednesday, October 19th. The Sun will rise at 8:04. It’ll be up for 10 hours and 46 minutes, setting at 6:50. The Moon, half way from full to last quarter, will rise at 9:58 this evening.

Low in the east this morning at 7:15 Jupiter might be glimpsed in the twilight. Jupiter’s rise time is at 6:28 a.m. Venus, Saturn and Mars are in the evening sky. Venus is briefly visible after sunset, low in the west-southwest. It will set at 8:16 p.m., following the Sun’s earlier setting times. Venus is still moving a bit southward and will still be hugging the southwestern horizon for the next month or so, but it’s high enough to spot with a reasonably low horizon. Mars and Saturn can be seen in the darkened sky after Venus sets. Mars is way out to the left of Saturn passing above the Teapot of Sagittarius. Saturn, spectacular in telescopes with its rings, will set at 9:09 p.m. Mars 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

Venus, Saturn and Mars at 7:30 p.m. October 19, 2016. Last night I saw Venus and Mars, but not Saturn with the naked eye at that hour. Created using Stellarium.

Saturn and Mars at 8:30 p.m. October 19, 2016. Created using Stellarium.

Jupiter rising at 7 a.m. this morning, October 19, 2016. Created using Stellarium.

The Moon as it might be seen in binoculars at 7 a.m. this morning, October 19, 2016. Created using Stellarium.

Planets and Moon at sunset and sunrise of a single night starting with sunset on the right on October 19, 2016. The night ends on the left with sunrise on October 20. If you are using Firefox right-click on the image and select View Image to enlarge the image. That goes for all the large images. Created using my LookingUp program.

10/17/2016 – Ephemeris – Europe’s ExoMars satellite and lander will reach Mars Tomorrow

Ephemeris for Tuesday, October 18th.  The Sun will rise at 8:02.  It’ll be up for 10 hours and 49 minutes, setting at 6:52.  The Moon, 2 days past full, will rise at 9:07 this evening.

You’ve probably haven’t heard of the ExoMars mission before or even recently.  That’s the way Mars missions go, due to their long cruise phase.  It was launched by the Europeans and Russians back in March.  ExoMars is an orbiter with an attached lander.  The lander named Schiaparelli after the famed 19th century astronomer, separated from the Trace Gas Orbiter two days ago to land on Mars.  A few hours later the orbiter made a thruster burn to miss Mars and not follow the lander into Mars’ atmosphere.  The lander will hit Mars’ atmosphere at about 10:52 a.m. tomorrow, with landing 5 minutes later.  The Schiaparelli lander will operate on batteries only with a lifetime of a few days.  It will take a few images as it lands, but will not take images from the surface.

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

Addendum

Artist’s visualization of releasing the Schiaparelli lander. Credit ESA.

Planetary Society’s Emily Lakdawalla’s blog post showing the ExoMars Mars arrival timeline:  http://www.planetary.org/blogs/emily-lakdawalla/2016/10140937-exomars-timeline.html