Archive
01/05/2016 – Ephemeris – The crescent moon is passing the morning planets
Ephemeris for Tuesday, January 5th. The Sun will rise at 8:20. It’ll be up for 8 hours and 56 minutes, setting at 5:16. The Moon, 3 days past last quarter, will rise at 4:48 tomorrow morning.
This morning the crescent Moon will be in the morning sky about half way between Venus below and Mars above. Reddish Mars is to the left of the bright blue-white star Spica nearly in the south at 7 a.m. Jupiter is way high in the south-southwest by then. Venus is approaching Saturn, and they will apparently cross paths this Saturday. By tomorrow morning the Moon will be much closer to Venus, with our Morning Star about 5 degrees, or 10 Moon diameters below and left of the thin crescent Moon, which should be exhibiting earthshine by then. By Thursday the Moon will be about the same distance to the left of Venus. The line that can be drawn through planets, along the Zodiac, is lying down as the Sun is slowly heading northward.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The travels of the crescent Moon by Venus and Saturn. Positions shown for 7 a.m. on consecutive mornings: January 5-7, 2016. The moon is shown twice its size for clarity. Created using Stellarium and GIMP.
12/18/2015 – Ephemeris – The Moon at first quarter tonight
Ephemeris for Friday, December 18th. The Sun will rise at 8:15. It’ll be up for 8 hours and 48 minutes, setting at 5:03. The Moon, at first quarter today, will set at 1:17 tomorrow morning.
By the time we see the moon tonight it will be at least 8 hours since the Moon passed the first quarter point and it’s terminator or sunrise line will appear slightly bowed. This time, since I can only point out a few features at a time, I’d like to point out three craters on the upper, north portion of the moon. They may be too small for binoculars, but fine for small telescopes. They make a nearly right triangle in Mare Imbrium, the Sea of Showers near the terminator. The largest is Archimedes, named for the 3rd century BC Greek mathematician, and inventor. The northern crater is Aristillus, named after a 3rd century BC astronomer, The other crater is Autolycus, named for a 4th century BC Greek astronomer.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The first quarter Moon on December 18 at 9 p.m. EST. Highlighted are the trio of craters of which Archimedes is the largest. Created using Virtual Moon Atlas.
Other features visible are the crater Plato, the Alpine Valley, the crater Alphonsus, which I’ve covered in the past. Search on them for their location and more information.
12/16/2015 – Ephemeris – The planet action is still in the morning
Ephemeris for Wednesday, December 16th. The Sun will rise at 8:13. It’ll be up for 8 hours and 49 minutes, setting at 5:02. The Moon, 2 days before first quarter, will set at 10:57 this evening.
Let’s check out the whereabouts of the bright naked eye planets. Mercury is becoming marginally visible very low in the southwest before it sets at 6 p.m. In the morning sky there are three bright planets. Jupiter will be the first to rise, at 12:15 a.m. in the east. Mars will rise next at 2:39 a.m. also in the east, followed by Venus at 4:41 a.m. in the east-southeast. Mars lies in line between Venus below and Jupiter above, almost halfway between the two. Don’t confuse Mars with the star Spica which is brighter and right below it. Saturn will rise at 6:54 a.m. in the east-southeast. Comet Catalina is a telescopic object about one and a half the width of a fist held at arm’s length above Venus and the same amount left of Mars.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The moon as it might look in binoculars at 8 p.m., December 16, 2015. Created using Stellarium.
The Morning planets at 7 a.m., December 17, 2015. Created using Stellarium.
Jupiter and moons in a telescope at 7 a.m. December 17, 2015. Created using Stellarium.
Venus as seen in a telescope as seen at the same magnification as Jupiter above, at 7 a,m. December 17, 2015. Created using Stellarium.
Comet Catalina and Mars for the next week. Note the magnitudes for the comet are about 1 magnitude too bright. It will take binoculars or a small telescope to spot the comet which will not show a tail visually. Created using Cartes du Ciel (Sky Charts).
This is a chart showing the sunrise and sunset skies for December 16, 2015 showing the location of the planets and the Moon at that time. Created using my LookingUp program. Click on the image to enlarge.
12/07/2015 – Ephemeris – Today the Moon will pass in front of the planet Venus
Ephemeris for Monday, December 7th. The Sun will rise at 8:06. It’ll be up for 8 hours and 56 minutes, setting at 5:02. The Moon, half way from last quarter to new, will rise at 5:04 tomorrow morning.
The Moon will pass in front of Venus between about 12:20 p.m. and 1:27 p.m. for the Interlochen, Traverse City Area. Times will vary as much as 5 minutes over the IPR listening area. Some sort of telescopic aid is needed to see Venus and the crescent Moon in daylight. The crescent Moon is quite faint, though Venus should be easier to spot because it’s brighter. I have a special post on my blog dated Saturday December 5th.. It’s titled Venus Occultation December 7, 2015 from Northern Michigan with all the details. My blog is bobmoler.wordpress.com, or do an Internet search for Bob Moler, That’s Moler spelled M-O-L-E-R, no extra letters. And hope for clear skies.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Animation of the occultation. Created using Cartes du Ciel (Sky Charts) and GIMP.
Venus Occultation December 7, 2015 from Northern Michigan
What is an occultation? An occultation is when one nearer celestial body covers or hides another, more distant body. The word occultation comes from occult which simply means hidden. No black magic is involved.
The occultation of Venus will occur on December 7, from 12:21 p.m. to 1:27 p.m. for the Grand Traverse Area, give or take a few minutes either way. The exact time depends on your location. This event would be a great sight if it occurred in the early morning skies before sunrise. Unfortunately it’s centered on 1 p.m. Venus and the Moon are visible in the daytime with a telescope and even binoculars, but are difficult to find. The Moon and Venus do make a beautiful sight in the morning in the 5 to 7 a.m. hours.
Disappearance of Venus at 12:20 p.m. Created using Cartes du Ciel (Sky Charts).
The trick to viewing this event is even finding the Moon or Venus. One could set up a telescope with tracking ability to track Venus throughout the morning. Unless you have a telescope Go To mount and can track the Moon, track Venus instead. The Moon moves about its own diameter with respect to the stars in an hour, so it will have to be constantly adjusted to keep pointed at the Moon. Actually Venus has a higher surface brightness than the Moon, so it should be easier to track, especially if the sky is hazy and the Moon isn’t visible.
Disappearance of Venus at 1:27 p.m. Created using Cartes du Ciel (Sky Charts).
Unlike a stellar occultation Venus will disappear over several seconds. A telescope capable to seeing Venus’ gibbous phase will see the bright edge of the Moon actually pass in front it. Venus will emerge from the Moon’s dark side which will be invisible. So Venus will slowly reappear next to the crescent Moon. Hoping for clear skies, and good luck.
If you are not located near Traverse City, you can use my technique to estimate the occultation times. I used Cartes du Ciel the free software found on the Internet at http://www.ap-i.net/skychart/en/start. Make sure that the program is set for topocentric positions under Setup/Solar System. And you have entered your position under Setup/Observatory. You can find your location in Google Earth.
You can also use Stellarium (http://stellarium.org). Just make sure the Moon is normal sized.
In both programs you can lock the Moon or Aldebaran in the center of the screen Pick a time in advance of the occultation and using the set time window walk the star towards the Moon, mark the time. Then walk the star out from the Moon and record the reappearance time. That’s it.
This should work with other planetarium programs too.
Animation of the occultation. Created using Cartes du Ciel (Sky Charts) and GIMP.
For better accuracy go to the International Occultation Timing Association (IOTA) website. Download and install their Occult4 program for Windows computers. Follow the instructions. When I ran the program for my location, the location I use for Interlochen/Traverse City (Since I live approximately half-way between the two). I got results within a half-minute of the IOTA Occult4 program results. So the approximation method using planetarium programs is valid.
Sun and Moon’s positions at the start of the occultation from northern Michigan. Note the Moon and Venus will be invisible to the naked eye. Created using Stellarium.
Sun and Moon’s positions at the end of the occultation from northern Michigan. Note the Moon and Venus will be invisible to the naked eye. Created using Stellarium.
When I made up the above images I really thought there would be snow on the ground by now. But what little we had has come and gone.
Occultation of Venus Visibility Map for North America. Credit: Astronomical Almanac Online -U.S. Nautical Almanac Office, United States Naval Observatory (USNO), in the United States and Her Majesty’s Nautical Almanac Office (HMNAO), United Kingdom Hydrographic Office (UKHO), in the United Kingdom.
12/03/2015 – Ephemeris – The Moon will pass by the morning planets in the next few days
Ephemeris for Thursday, December 3rd. The Sun will rise at 8:01. It’ll be up for 9 hours and 1 minute, setting at 5:03. The Moon, at last quarter today, will rise at 1:11 tomorrow morning.
The Moon will be making a grand procession by the morning planets in the next few days, culminating with passing in front of Venus just after noon on Monday. This morning the Moon is approaching Jupiter to its lower left. By tomorrow morning Jupiter will be just above the Moon. Saturday morning the Moon will be approaching Mars, 12 of its diameters to its lower left. Sunday morning finds the crescent Moon between Mars and Venus with Mars 8 diameters above and right of the Moon. Monday Morning at 6 a.m. the Moon will be closing on Venus, with the brilliant planet just 4 moon diameters below left of the thin crescent Moon. Sharp eyed binocular and telescopic observers will be able see the Moon occult Venus after noon.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Animation of the Moon’s passage by the morning planets and Comet Catalina from December 2nd through the 7th, 2015. Created using Stellarium and GIMP.
12/02/2015 – Ephemeris – All the bright planet action is in the morning
Ephemeris for Wednesday, December 2nd. The Sun will rise at 8:00. It’ll be up for 9 hours and 2 minutes, setting at 5:03. The Moon, 1 day before last quarter, will rise at 12:12 tomorrow morning.
Let’s check out the whereabouts of the bright naked eye planets. Saturn and Mercury are too close to the direction of the Sun to be seen now. In the morning sky there are three bright planets. Jupiter will be the first to rise, at 1:03 a.m. in the east. Mars will rise next at 2:52 a.m. in the east, followed by Venus at 4:13 a.m. also in the east. Mars lies in line between Venus below and Jupiter above, almost halfway between Venus and Jupiter. The Moon will pass each of these planets in the next few days culminating by passing in front of Venus Monday. Comet Catalina will be about the width of a fist held at arm’s length below and left of Venus and will slowly be moving to the upper left and be level with Venus on the 6th.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Moon, Jupiter, Mars and Venus appear in the southeast at 6 a.m., December 3, 2015. Note that Comet Catalina is near Venus. Created using Stellarium.
Jupiter and moons in a telescope at 6 a.m. December 3, 2015. Created using Stellarium.
Venus as seen in a telescope as seen at the same magnification as Jupiter above, at 6 a,m. December 3, 2015. Created using Stellarium.
The Moon as seen in a binoculars or small telescope at 6 a,m. December 3, 2015. Created using Stellarium.
Comet Catalina and Venus for the next week. Note the magnitudes for the comet are about 2 magnitude too bright. It will take binoculars or a small telescope to spot the comet.
12/01/2015 – Ephemeris – Previewing December skies
Ephemeris for Tuesday, December 1st. The Sun will rise at 7:59. It’ll be up for 9 hours and 4 minutes, setting at 5:03. The Moon, 2 days before last quarter, will rise at 11:13 this evening.
December is the month with the shortest daylight hours. Winter will officially arrive at the winter solstice on the 21st at 11:48 p.m. There will be little movement in the sunset times: In the Traverse City/Interlochen area this will be from 5:03 tonight, down to 5:02 and then advancing to 5:11 at the end of the month. There is more movement in the sunrise times which will advance from 7:59 today to 8:20 on the 31st. There is also little movement of daylight hours. The noontime sun will hang around 22 to 23 degrees above the southern horizon all month. We have some great events this month, from an occultation of Venus by the moon on the 7th, to the Geminid meteors on the 14th and Comet Catalina will be seen in binoculars on mornings all this month.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addenda
Star Chart for December 2015. Created using my LookingUp program. Click on image to enlarge.
The planets and stars are plotted for the 15th at 9 p.m. EST. That is chart time. Note, Traverse City is located 45 minutes behind our time meridian. To duplicate the star positions on a planisphere you may have to set it to 45 minutes earlier than the current time.
Evening astronomical twilight ends at 6:48 p.m. EST on December 1st, decreasing a minute 9 days later before increasing to 6:57 p.m. EST on the 31st.
Morning astronomical twilight starts at 6:15 a.m. EST on December 1st, and increasing to 6:34 a.m. EST on the 31st.
Add a half hour to the chart time every week before the 15th and subtract and hour for every week after the 15th.
For a list of constellation names to go with the abbreviations click here.
- Pointer stars at the front of the bowl of the Big Dipper point to Polaris the North Star.
- The Summer Triangle is still up and is shown in red.
- GemR is the Geminid meteor shower radiant
Calendar of Planetary Events
Credit: Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC)
To generate your own calendar go to http://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html
Times are Eastern Daylight Time. Some additions made to aid clarity.
Date Local Event
Time EST
Dec 01 Tu Venus: 43.3° W 03 Th 2:41am Last Quarter 04 Fr 1:21am Moon-Jupiter: 2° N 04 Fr 1:33pm Moon Ascending Node 05 Sa 9:56am Moon Apogee: 404800 km 05 Sa 9:40pm Moon-Mars: 0.1° N - Occultation ** 07 Mo 11:55am Moon-Venus: 0.7° S - Occultation * 11 Fr 5:29am New Moon 12 Sa 3:15am Moon South Dec.: 18.4° S 14 Mo 12:48pm Geminid Shower: ZHR = 120 17 Th 9:32pm Saturn-Antares: 6.2° N 18 Fr 10:13am Moon Descending Node 18 Fr 10:14am First Quarter 21 Mo 3:53am Moon Perigee: 368400 km 21 Mo 11:48pm Winter Solstice 22 Tu 9:00pm Ursid Shower: ZHR = 10 23 We 9:16pm Mars-Spica: 3.5° N 23 We 2:09pm Moon-Aldebaran: 0.7° S 25 Fr 2:30am Moon North Dec.: 18.4° N 25 Fr 6:11am Full Moon 28 Mo 9:59pm Mercury Elongation: 19.7° E 29 Tu 3:30pm Moon-Regulus: 2.9° N 31 Th 12:55pm Moon-Jupiter: 1.6° N 31 Th 3:19am Moon Ascending Node Jan 01 Fr Venus: 37.9° W
* The occultation will be visible in the US, except extreme southwestern Alaska and Hawai’i; and Canada down to Panama. In the Grand Traverse area of Michigan the occultation starts around 12:20 p.m. and ends around 1:27 p.m. This is a daytime event for most of the US. Note that the actual time depends on your exact location. I’ll have more information in a non Ephemeris post on Saturday the 5th. The Occultation map is here.
** On December the 5th there will be an occultation of Mars visible across the Indian Ocean and much of Australia. That occultation map is here.
Estimating occultation timings for your location
I used Cartes du Ciel the free software that I have a link to on the right. Make sure that the program is set for topocentric positions under Setup/Solar System. And you have entered your position under Setup/Observatory. You can find your location in Google Earth, or your GPS device or smart phone.
You can also use Stellarium. Just make sure the Moon is normal sized.
In both programs you can lock the Moon or Aldebaran in the center of the screen Pick a time in advance of the occultation and using the set time window walk the star towards the Moon, mark the time. Then walk the star out from the Moon and record the reappearance time. That’s it.
This should work with other planetarium programs too.
For better accuracy go to the International Occultation Timing Association (IOTA) website. Download and install their Occult4 program for Windows computers. Follow the instructions. When I ran the program for my location, the location I use for Interlochen/Traverse City (Since I live approximately half-way between the two). I got results within a half-minute of the IOTA Occult4 program results. So the approximation method using planetarium programs is valid.
Comet C/2013 US10 (Catalina)
This comet has been hiding for the last two years after its discovery, moving into the far southern hemisphere of the sky. However this month it has emerged into our morning sky. This comet is a one time visitor from the Oort Cloud to the inner solar system and will be ejected into interstellar space. It passed perihelion on November 15th, coming just inside the Earth’s orbit on the other side of the Sun from us. It’s orbit will be headed northward and a bit toward us, so it will keep its brightness steady.
The position marks in the chart have the date and the magnitude. However the comet is currently appearing one magnitude dimmer than shown. So instead of appearing as nearly 5th magnitude, it will really be 6th magnitude. It’s definitely a binocular or telescopic object.
According to the brightness graph the comet began to under perform in brightness back in September, however, according to a new brightness formula the comet may increase in brightness by a magnitude by late February when it will be well placed for viewing all night. To monitor the brightness reports from observers go to http://www.aerith.net/comet/catalog/2013US10/2013US10.html.
The tracks of Comet C/2013 US10 (Catalina) for December 2015 along with part of Venus’ track. Created using Cartes du Ciel (Sky Charts).
11/25/2015 – Ephemeris – The occultation of Aldebaran is tomorrow morning!
Ephemeris for Wednesday, November 25th. The Sun will rise at 7:52. It’ll be up for 9 hours and 14 minutes, setting at 5:06. The Moon, at full today, will rise at 5:26 this evening.
Tomorrow morning between about 5:38 and 6:29 a.m. the Moon will pass in front of the bright star Aldebaran. The event is called an occultation. Aldebaran is the bright reddish star in the V-shaped face of the constellation Taurus the bull, which is seen in the sky charging Orion the hunter in the evening sky now. By the time of this event, they will have moved into the west. Aldebaran, though bright, doesn’t hold a candle to the nearly full Moon. I know that a holiday is a good day to sleep in, unless you are getting an early start on preparing the Thanksgiving feast. In any case the earlier you get out to spot Aldebaran the easier it will be to find in the Moon’s glare. Check out my posts on bobmoler.wordpress.com for more information.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Here’s the Moon hiding Aldebaran in its glare at 5:30 a.m. tomorrow morning November 26, 2015. Created using Stellarium.
An occultation animation starting at 5:19 a.m. EST showing 10 minute intervals. Computer generated graphics cannot produce a point star. Aldebaran will wink out and back in an instant. Created using Cartes du Ciel (Sky Charts) and GIMP.
11/23/2015 – Ephemeris – An occultation of Aldebaran by the Moon will be visible to much of the northern US Thursday morning
Ephemeris for Monday, November 23rd. The Sun will rise at 7:49. It’ll be up for 9 hours and 18 minutes, setting at 5:08. The Moon, 2 days before full, will set at 5:58 tomorrow morning.
Thursday morning, Thanksgiving Day here in the US, the Moon will occult or pass in front of the bright star Aldebaran for the northern half of the United States, and Canada. I have a special post on my blog dated yesterday, November 22nd. It’s titled Aldebaran Occultation November 26, 2015 from Northern Michigan (click here) with all the details. My blog is bobmoler.wordpress.com, or do an Internet search for Bob Moler, That’s Moler spelled M-O-L-E-R, no extra letters. Aldebaran is the bright orange star in the face of the constellation Taurus the bull. You will need at least a pair of binoculars to pick out Aldebaran next to the Moon. Aldebaran will disappear at about 5:38 a.m. and reappear about 6:29 a.m. for Interlochen and Traverse City.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location. The November 22 post has instructions on how to calculate the occultation times for your location, and has a map to see if you can view the occultation at all.
Addendum
An occultation animation starting at 5:19 a.m. EST showing 10 minute intervals. Not that the computer generated graphics cannot produce a point star. Aldebaran will wink out and back in an instant. Created using Cartes du Ciel (Sky Charts) and GIMP.
Bob Moler's Ephemeris Blog 