Archive
11/05/2015 – Ephemeris – The Moon will be among the morning planets in the next two days
Ephemeris for Thursday, November 5th. The Sun will rise at 7:25. It’ll be up for 10 hours and 0 minutes, setting at 5:26. The Moon, 2 days past last quarter, will rise at 2:23 tomorrow morning.
Over the next two mornings the Moon will pass, first, the planet Jupiter and then on Saturday Mars and Venus. These will be readily visible at 6 a.m. and less so at 7 a.m. when twilight is brighter. This month and next we will have two times the Moon will actually pass in front of another bright celestial object. Both will occur in the morning. These events are called occultations. The first will be an occultation of the bright star Aldebaran, the bright star in Taurus the bull, which I sometimes call the bull’s angry bloodshot eye. That will occur on the morning of November 26th. The next will be really spectacular. On December 7th the crescent Moon will occult the planet Venus. I’ll keep you updated on both these events.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Animation of the Moon passing Jupiter tomorrow morning and Mars and Venus Saturday morning. Created using Stellarium and GIMP.
10/21/2015 – Ephemeris – The bright planets and an anniversary star party
Update 5:05 p.m.:
The star party at the Sleeping Bear Dunes has been canceled due to clouds.
Ephemeris for Wednesday, October 21st. The Sun will rise at 8:05. It’ll be up for 10 hours and 42 minutes, setting at 6:48. The Moon, 1 day past first quarter, will set at 2:00 tomorrow morning.
We’ve got a busy day. The planet Saturn will be low in the west-southwest after sunset and will set at 8:31 p.m. In the morning sky the brilliant planet Venus will rise at 4:05 and be quite high at this program’s air time. Jupiter will be just below and left of it. Mars will be below and left of Jupiter by a similar amount. Both rise within 20 minutes of Venus. Far below and left will be Mercury which will rise at 6:38. Tonight is the last star party of the year at the Sleeping Bear Dunes National Lakeshore. This is the lakeshore’s 45th anniversary. It will held starting at 8 p.m. at Pierce Stocking Drive Stop #3 the Dunes Overlook if it’s clear, Park at Picnic Mountain. The Moon will be the big attraction tonight. The Grand Traverse Astronomical Society has been holding star parties at the Sleeping Bear Dunes since the park’s 40th anniversary in 2010.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Saturn and the Moon (at twice normal size) at 7:30 p.m. October 21, 2015. Created using Stellarium.
The telescopic Moon tonight, October 21, 2015, for the star party at Sleeping Bear Dunes. Created using Virtual Moon Atlas.
The morning planets at 7 a.m., October 22, 2015. Created using Stellarium.
This is a chart showing the sunrise and sunset skies for October 21, 2015 showing the location of the planets and the Moon at that time. The charts are rotated 90 degrees to more clearly show the traffic jam of the morning planets. Created using my LookingUp program. Click on the image to enlarge.
10/19/2015 – Ephemeris – Where did the Moon come from?
Ephemeris for Monday, October 19th. The Sun will rise at 8:03. It’ll be up for 10 hours and 48 minutes, setting at 6:51. The Moon, 1 day before first quarter, will set at 11:51 this evening.
Only two planets in the solar system have moons at least a quarter the size of the planet they orbit: The Earth and Pluto. The Moon is a bit more than a quarter the Earths diameter while Pluto’s moon Charon is half its size. Probably in the early days of the solar system, some four and a half billion years ago collisions were rather common. It is thought by many planetary scientists that a Mars sized protoplanet collided with the proto-earth with a glancing blow to rip off much of the Earth’s crust, thrust it into orbit where it coalesced into the Moon. It seems that Pluto’s Charon may have been formed much the same way. Some thing the varying axial tilts of the planets may have been caused the same way by smaller objects.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The hypothetical collision of a Mars sized body with the young Earth. Credit: Joe Tucciarone via NASA
Breaking News
Robert Farquhar the man behind the ISEE-3 spacecraft, the first to hang out at the Earth-Sun L1 point between the Earth and the Sun back in 1978 passed away yesterday. In 1982 he “stole” the spacecraft and through an amazing number of maneuvers using very little fuel managed to send it through the tail of Comet Gicobini-Zinner ahead of the fleet of spacecraft then aimed at Halley’s Comet. Last year when the then renamed spacecraft ICE approached the Earth, he hatched a plan to return the spacecraft to its L1 position. Unfortunately apparently there was not enough fuel pressure to complete the burns necessary for the task. I’ll have a program on Robert Farquhar next Monday.
10/15/2015 – Ephemeris – More planet and Moon action
Ephemeris for Thursday, October 15th. The Sun will rise at 7:57. It’ll be up for 11 hours and one minute, setting at 6:58. The Moon, 3 days past new, will set at 8:41 this evening.
Tonight the planet Saturn will be seen about 15 moon-diameters left of the thin crescent Moon. We are getting close to the end of Saturn’s evening visibility. It will be pretty much lost in the evening twilight by the end of the month. In the morning sky, Mercury will be at greatest elongation by tomorrow morning. It will be at an angle of only 18 degrees from the Sun, however that angle won’t diminish much over the next week, and Mercury will actually get a bit brighter because its phase becomes fuller. Remember it is illuminated by the sun and it is beginning to move around the back of the Sun. Both Mercury and Venus show phases in a telescope like the Moon as they move around the sun.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Animation rocking back and forth between 7:45 p.m. on October 15th and 16th (2015_. Created using Stellarium.
10/14/2015 – Ephemeris – The planet get together in the morning
Ephemeris for Wednesday, October 14th. The Sun will rise at 7:56. It’ll be up for 11 hours and 3 minutes, setting at 7:00. The Moon, 2 days past new, will set at 8:06 this evening.
Lets see what’s happening with the bright planets. Saturn is alone in the evening sky spotted by 8 p.m. low in the west-southwestern sky near the bright star Antares to its left. Antares has a reddish hue, while Saturn is brighter and yellowish. Both these colors are enhanced by being low to the horizon. Saturn will set at 8:56 p.m. The rest of the planets are in the morning sky and seeing more action. Brilliant Venus, the morning star, will rise at 4 a.m. a bit north of east. Below and left of Venus is bright Jupiter, though not as bright as Venus. Above it tomorrow is dim Mars. They will pass each other on Saturday. Jupiter will rise at 4:37 preceded by 7 minutes by Mars. Mercury is way below these, but brightening. It will rise at 6:20.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Saturn and Antares appear in west-southwestern twilight with the thin crescent Moon, shown twice its actual size to show up at all, at 7:45 p.m., October 14, 2015. Created using Stellarium.
The morning planets getting together at 7 a.m. Mercury will be falling back toward the Sun after tomorrow. Created using Stellarium.
Apparent sizes of the morning planets Venus, Mars and Jupiter as seen through a telescope. Created using Cartes du Ciel (Sky Charts).
This is a chart showing the sunrise and sunset skies for October 14, 2015 showing the location of the planets and the Moon at that time. Created using my LookingUp program. Click on the image to enlarge.
10/09/2015 – Ephemeris – The Moon is seen with the morning planets this weekend
Ephemeris for Friday, October 9th. The Sun will rise at 7:50. It’ll be up for 11 hours and 18 minutes, setting at 7:09. The Moon, 3 days before new, will rise at 5:31 tomorrow morning.
This morning up to about 7:15 look to the east at the crescent Moon and the planets. The Moon is between Venus above and Jupiter just below and to the left. Mars will be a bit above and just left of the Moon. Mercury will be farther below the moon to the left and about 22 degrees below the Moon (that’s about twice the width of a fist held at arm’s length.) By Sunday morning the thin sliver of the Moor will be near Mercury with the tiny planet just above left of the Moon. Next Thursday the 15th, Mercury will climb to its greatest angular distance or elongation west of the Sun. It will be getting a bit brighter for a while because even though it’s moving away from us, its phase will be getting fuller. Remember it’s illuminated by the sun.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Morning planet animation for 7 a.m. October 8 to 11, 2015. Created using Stellarium and GIMP.
10/08/2015 – Ephemeris – The Draconid meteors will reach peak overnight tonight
Ephemeris for Thursday, October 8th. The Sun will rise at 7:49. It’ll be up for 11 hours and 21 minutes, setting at 7:10. The Moon, half way from last quarter to new, will rise at 4:33 tomorrow morning.
For this and the next few morning the Moon will pass the morning planets. This morning it’s Venus, tomorrow it will be near Mars and Jupiter, and Sunday morning it will be near Mercury.
This evening is the expected peak of the Draconid meteor shower. We can expect anything between zero and hundreds of meteors an hour. The calculated time of the peak number will be around 1:40 a.m. (5:40 UT, October 9). The point in space they will appear to come from is the head of the constellation Draco the dragon, a bit north of the bright star Vega, high in the west in the evening. Meteor experts don’t expect much from the shower this year, but the Draconids are capricious, you never know what to expect. However we do expect them to be slow-moving.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The entire sky dome including the Draconid Radiant (DraR) for 9 p.m. October 8, 2015 (1:00 UT 10/9). Created with my LookingUp program.
The entire sky dome including the Draconid Radiant (DraR) for 1:40 a.m. October 9, 2015 (05:40 UT). Created with my LookingUp program.
Morning planet animation for 7 a.m. October 8 to 11, 2015. Click on image to enlarge. Note the Moon’s size is tripled for visibility. Created using Stellarium 0.13 and GIMP.
10/07/2015 – Ephemeris – Saturn lingers in the evening, but the planet action is in the morning
Ephemeris for Wednesday, October 7th. The Sun will rise at 7:47. It’ll be up for 11 hours and 24 minutes, setting at 7:12. The Moon, 3 days past last quarter, will rise at 3:34 tomorrow morning.
Lets see what’s happening with the bright planets. Saturn is alone in the evening sky spotted by 8:30 p.m. low in the southwestern sky near the bright star Antares to its left. Antares has a reddish hue, while Saturn is brighter and yellowish. Both these colors are enhanced by being low to the horizon. Saturn will set at 9:22 p.m. The rest of the planet action in the morning sky is getting interesting. Brilliant Venus, the morning star, will rise at 3:58 a.m. a bit north of east. Tomorrow it will be at its greatest separation from the sun and start to fall back. The Moon will be near Venus tomorrow morning. The star Regulus is near Venus. Much dimmer Mars, brighter Jupiter and finally Mercury will rise at 4:35, 4:57 and 6:37 respectively.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Saturn and setting zodiacal constellations at 8:30 .m. on October 7, 2015. Create using Stellarium.
Morning Planets and the Moon at 6:30 a.m. on October 8, 2015. The Moon is shown twice actual size. Created using Stellarium.
This is a chart showing the sunrise and sunset skies for October 7, 2015 showing the location of the planets and the Moon at that time. Created using my LookingUp program. Click on the image to enlarge.
09/28/2015 – Ephemeris – The Harvest Moon effect
Ephemeris for Monday, September 28th. The Sun will rise at 7:36. It’ll be up for 11 hours and 52 minutes, setting at 7:29. The Moon, 1 day past full, will rise at 8:00 this evening.
Yesterday’s full moon was the famous Harvest Moon, the nearest full moon to the autumnal equinox. This is a time of the full and waning gibbous moons in the next few days rising in twilight. In the old days before electric lights it helped farmers by effectively lengthening the hours of light to gather in the crops. The Moon on average rises 50 minutes later each night. The interval between tonight’s moon rise and tomorrow’s will be 38 minutes. The interval between Tuesday and Wednesday will be 42 minutes. This year’s harvest moon effect is spoiled a bit because the Moon was at perigee Sunday, the so-called supermoon, so it’s moving faster in its orbit than average. Like the Sun, the Moon always appears orange or red near the horizon.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The positions of the Moon from September 28 to October 1, 2015. Note the path of the Moon. At Harvest Moon in northern Michigan time it makes less than a 45 degree angle with the horizon. For other latitudes it’s less than (90 – latitude). shorthand term for 90 – latitude is co-latitude. Created using Cartes du Ciel.
The closer to horizontal the Moon’s path is the shorter the difference in night-to-night rise times.
09/23/2015 – Ephemeris – One planet visible in the evening and three in the morning
Ephemeris for Wednesday, September 23rd. The Sun will rise at 7:30. It’ll be up for 12 hours and 7 minutes, setting at 7:38. The Moon, 2 days past first quarter, will set at 3:09 tomorrow morning.
Lets look at the planets for this first day of autumn. Saturn is alone in the evening sky spotted by 9 p.m. low in the southwestern sky near the bright star Antares to its left. Antares has a reddish hue, while Saturn is brighter and yellowish. Both these colors are enhanced by being low to the horizon. Saturn will set at 10:13 p.m. The rest of the planet action has moved to the morning sky. Venus, the morning star, will rise at 4:09 a.m. a bit north of east. Much dimmer Mars will rise at 4:44 a.m. in the east-northeast. Jupiter is beginning to be visible in the morning sky and will rise at 5:37 in the east-northeast. Mercury, though in the evening sky, sets too soon after the Sun to be visible.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Saturn and the Moon with setting southern summer stars at 8:30 p.m. on September 23, 2015. The Moon is shown twice actual size. Created using Stellarium.
What Saturn and its moons might appear like in a telescope at 8:30 p.m., September 23, 2015. Small telescopes will show only the moon Titan. Created using Stellarium. The telescopic planet charts are all displayed at the same scale.
The Moon as it might be seen in binoculars at 8:30 p.m. September 23, 2015. Created using Stellarium.
Venus, Mars and Jupiter with the constellation Leo at 6:30 a.m. September 24, 2015. Created using Stellarium.
Venus in a telescope at 6:30 a.m. September 24, 2015. Created using Stellarium.
Jupiter and moons in a telescope at 6:30 a.m. September 24, 2015. Created using Stellarium.
This is a chart showing the sunrise and sunset skies for September 23, 2015 showing the location of the planets and the Moon at that time. Created using my LookingUp program. Click on the image to enlarge.
Bob Moler's Ephemeris Blog 