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04/20/2017 – Ephemeris – The Lyrid meteors are reaching their peak now
Ephemeris for Thursday, April 20th. The Sun rises at 6:49. It’ll be up for 13 hours and 44 minutes, setting at 8:33. The Moon, 1 day past last quarter, will rise at 4:20 tomorrow morning.
We are in a period where the Lyrid meteors appear. This capricious shower peaks at various times and with a variety of peak numbers from 14 to 90 per hour. The expected peak will be April 22nd at 8 a.m. The radiant point, from where the meteors seem to come, lies between the constellation Lyra and its bright star Vega and Hercules to the west of it. The radiant point starts the evening low in the northeast and moves nearly overhead when the Moon finally rises. The meteors, sometimes called falling stars will appear all over the sky, but can be traced back to that radiant point. The best time to see these or any meteor shower is when the radiant point is highest in the sky. That will be Saturday morning.
The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Location of the Lyrid meteor radiant at midnight. Note that the radiant point is a spot that the meteors can be back tracked to. The meteors will appear all over the sky. If they appear near the radiant they will appear to move the slowest, since their actual motion is mostly toward the observer. Created using Stellarium.
The display of meteor shower radiants is a plug-in in the latest versions of Stellarium.
08/11/2016 – Ephemeris – The Perseid meteors will peak tonight!
Ephemeris for Thursday, August 11th. The Sun rises at 6:41. It’ll be up for 14 hours and 12 minutes, setting at 8:53. The Moon, 1 day past first quarter, will set at 1:31 tomorrow morning.
This evening and tomorrow morning we should see the peak of the Perseid Meteor Shower. There is the expected broad peak of the shower which for us is after sunrise. However the meteoroid stream isn’t monolithic. Each pass of the comet in the inner solar system superimposes its debris on the general stream, so we will have increased activity all night tonight and even into Saturday morning. In general Perseid meteors will be seen to come from the northeast. The evening view will be hampered by the Moon which will drown out the dimmer meteors. The best time to view is after the Moon sets at 1:31 tomorrow morning until morning twilight becomes noticeable around 5 a.m. when over 100 meteors might be spotted an hour.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Perseid meteor shower radiant a about 2 a,m, during the period of the shower. Created using my LookingUp program.
Here are some meteors seen in the 2007 Perseid meteor shower taken by Scott Anttila. The image is centered on Cassiopeia. The radiant is low and a bit left of center in the image. The Double Cluster is seen below center and the Great Andromeda Galaxy is seen on the right just above center.
My best Perseid photo. From the 70’s.
08/10/2016 – Ephemeris – The planets tonight
Ephemeris for Wednesday, August 10th. The Sun rises at 6:39. It’ll be up for 14 hours and 15 minutes, setting at 8:55. The Moon, at first quarter today, will set at 12:55 tomorrow morning.
Today we turn from the small meteoroids that orbit the Sun that are producing the Perseid Meteor Shower to the larger members of the solar family, namely the bright planets. Venus and Mercury are very low in the west-northwest and will set at 9:44 and 9:50 p.m. respectively. Jupiter is in the west in the evening. It will set at 10:19 p.m. Mars, Saturn and the star Antares start the evening in the south-southwestern sky as a tightening triangle, moving to the southwest during the evening. Antares, whose name means Rival of Mars is below Saturn with brighter Mars to the right. The Red Planet is back in Scorpius. It will set at 12:46 a.m. Mars is moving rapidly to the east against the stars. Saturn is spectacular in telescopes, with its rings. Saturn will set at 1:34 a.m.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Venus, Mercury and Jupiter at 9:25 p.m. (30 minutes after sunset), August 10, 2016. Created using Stellarium.
The planets, Moon and constellations at 10 p.m., August 10, 2016. Created using Stellarium.
The Moon as it might appear in binoculars tonight, August 10, 2016 at 10 p.m. Created using Stellarium.
Saturn and its moons at 10 p.m. August 10, 2016. Created using Cartes du Ciel (Sky Charts).
Planets at sunset and sunrise of a single night starting with sunset on the right on August 10, 2016. The night ends on the left with sunrise on August 11. Actually all the naked eye planets are in the evening sky. Also shown is the Perseid meteor shower radiant. 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.
Also shown is the Perseid meteor shower radiant.
05/03/2016 – Ephemeris – Halley’s Comet is back… In little bitty pieces
Ephemeris for Tuesday, May 3rd. The Sun rises at 6:29. It’ll be up for 14 hours and 21 minutes, setting at 8:50. The Moon, 3 days before new, will rise at 5:23 tomorrow morning.
There’s a meteor shower happening this week that’s a tough one for observers as far north as we are. It’s the Eta Aquariids: seeming to come from the Water Jar asterism of the constellation Aquarius the water bearer. It will reach peak on Thursday the 5th, however the radiant point rises around 3:30 a.m., and twilight starts an hour and a half later. The radiant is also low in the southeastern part of the sky. The meteors are fast-moving and many of them are bright. They are bits shed by Halley’s Comet and left in its orbit. The Earth passes close to Halley’s orbit twice a year: In late October as the particles come in from the outer solar system, and again in early May as they head back out again. We’ll see souvenirs of Halley’s Comet before it returns in 2061.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The Eta Aquarid radiant at the peak of the shower. The radiant moves slowly to the east with time. Credit: Bob Moler’s LookingUp program.
This meteor shower is low for us in the Northern Hemisphere, but it will be great for those Down Under. The Moon is even cooperating this year, by getting out of the way. The active dates for the shower are April 19th to May 28th. The velocity of the meteoroids that strike the atmosphere is 66 km/s. Halley’s Comet, and thus its debris is traveling in a retrograde orbit, going the wrong way in a one way solar system, which is why the speed of the particles is so high.
12/11/2015 – Ephemeris – The Geminid meteor shower will be cranking up this weekend
Ephemeris for Friday, December 11th. The Sun will rise at 8:09. It’ll be up for 8 hours and 52 minutes, setting at 5:02. The Moon is new today, and won’t be visible.
Over the weekend and through Monday night the Geminid Meteor shower will be seen. This shower is actually the bet of the year, with higher hourly counts of meteors than the more famous Perseid meteor shower of August. Around here the cold weather and the more than even chance that it will be cloudy have kept this astronomer from having seen even one. Maybe this year. The Geminids can be seen all night because the radiant point is in the northern sky, well north of the celestial equator at least. At 9 p.m. the constellation Gemini rises sideways with the namesake of the twins, the stars Castor and Pollux vertically aligned in the east with Castor on top. The closest to the peak numbers will be seen Monday early morning and Monday night.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
All Sky view one hour intervals for The Geminid meteor shower the night of December 13-14, 2015.. Note the radiant “GemR”. Created with my LookingUp program and GIMP.
Note the times are in Universal time conversion to local time.
UT EST 2 9 p.m. 3 10 p.m. 4 11 p.m. 5 12 m. 6 1 a.m. 7 2 a.m. 8 3 a.m. 9 4 a.m. 10 5 a.m. 11 6 a.m.
For locations other than EST Eastern Standard time (UT – 5 hours), just use EST as your local time. The latitude is set for near 45º north.
08/11/2015 – Ephemeris – Perseid meteor shower is tomorrow night
Ephemeris for Tuesday, August 11th. The Sun rises at 6:40. It’ll be up for 14 hours and 14 minutes, setting at 8:55. The Moon, 3 days before new, will rise at 4:51 tomorrow morning.
The Perseid meteor shower is growing in numbers of meteors seen per hour. The expected peak is Thursday morning about a quarter after 2. However the peak time is only really known statistically after the event. The point in the sky from which the meteors or shooting stars seem to come from is called the radiant and it is near the constellation of Perseus. The meteors will appear all night from dusk to dawn. The peak number of meteors can be up to 90 an hour. No telescope is needed. Just lie down on a blanket and look up. The darker your sky the better. One of the darkest skies around is at the Sleeping Bear Dunes National Lakeshore. I will be leading an all night meteor shower watch at the Dune Climb Wednesday night til dawn if it’s clear.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Here are some meteors seen in the 2007 Perseid meteor shower taken by Scott Anttila. The image is centered on Cassiopeia. The radiant is low and a bit left of center in the image. The Double Cluster is seen below center and the Great Andromeda Galaxy is seen on the right above center. Click on the image to enlarge.
Position of the Perseid radiant and stars in all-sky plots for 3 times during the night: 11 p.m., 2 a.m., & 5 a.m.
11 p.m. August 12, 2015. Created using Bob Moler’s LookingUp program for Windows.
2 a.m. August 13, 2015. Created using Bob Moler’s LookingUp program for Windows.
5 a.m. August 13, 2015. Created using Bob Moler’s LookingUp program for Windows.
12/12/2014 – Ephemeris – The Geminids will zip through again this weekend
Ephemeris for Friday, December 12th. The sun will rise at 8:10. It’ll be up for 8 hours and 52 minutes, setting at 5:02. The moon, 2 days before last quarter, will rise at 11:19 this evening.
The Geminid meteor shower will reach its peak early Sunday morning, however the bright moon , rising after midnight will interfere. The Geminids, however do have a number of really bright fireballs for which the Moon won’t matter. The good news is that the Geminids will be visible all night. You don’t have to wait until the morning hours to see them. So around midnight Saturday night will probably be the best time to see them. Also the shower has a broad peak and there may be another peak on Monday or Tuesday night and morning. The peak numbers per hour for the Geminids will be close to 120. That’s the best for any year in and year out shower. To bad it occurs in such a cloudy month.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
The numbers of Geminids are already rising.
NASA’s Meteoroid Environment Office plots of fireball orbits for the night of December 10-11, 2014. The large number of yellow orbits oriented toward 2 o’clock are Geminids. Check spaceweather.com for each day’s fireball orbits. This plot includes 22 Geminid fireballs. Credit NASA via Spaceweather.com
Geminid Radiant
The Eastern sky got the Geminid meteor shower at 8 p.m. December 13, 2014. Created using Stellarium.
The Eastern sky got the Geminid meteor shower at midnight December 14, 2014. Created using Stellarium.
Remember Geminids can be seen all over the sky. It’s their streaks that can be extended back to the radiant.
12/11/2014 – Ephemeris – The Geminid meteors will reach peak numbers Saturday night to Sunday morning
Ephemeris for Thursday, December 11th. The sun will rise at 8:09. It’ll be up for 8 hours and 53 minutes, setting at 5:02. The moon, 3 days before last quarter, will rise at 10:21 this evening.
This weekend is the peak of the Geminid meteor shower. It is the best meteor shower of the year and it is getting more active over the years. The projected peak numbers is 120 meteors an hour spotted by a single observer when the radiant of the shower is overhead. It’s known as the zenithal hourly rate (ZHR). Anyway, the radiant is the point in space where the meteors seem to come from, which is near the star Castor in the constellation Gemini from which the shower gets its name. The meteors will be seen all over the sky, but they all can be traced back to the radiant. The body responsible for this meteor shower is an asteroid rather than a comet. It comes very close to the sun, so may crumble due to heat stress. I suppose I can’t resist this: That’s how the asteroid crumbles.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Geminid Radiant. From my LookingUp program.
The Eastern sky got the Geminid meteor shower at 8 p.m. December 13, 2014. Created using Stellarium.
The Eastern sky got the Geminid meteor shower at midnight December 14, 2014. Created using Stellarium.
The Stellarium charts differ from mine at top in how the constellation lines are drawn, especially Gemini. In all charts Castor is not labeled. However it is the bright star above Pollux. The meteors will will appear all over the sky, but true Geminids can be traced back near Castor. Also when the radiant is lowest in the sky, thought the numbers of meteors will be low, the brighter meteors will produce long streaks, since the will hit our atmosphere at a glancing angle.
08/12/2014 – Ephemeris – Comet Swift-Tuttle progenitor of the Perseid meteors
Ephemeris for Tuesday, August 12th. The sun rises at 6:41. It’ll be up for 14 hours and 11 minutes, setting at 8:52. The moon, 2 days past full, will rise at 9:50 this evening.
The Perseid meteor shower will reach its peak later this evening. The moon will still interfere with all but the brightest meteors. The meteors are caused by bits of sand grain to pea sized rubble given off by Comet Swift-Tuttle on past runs through the inner solar system. As comets go Comet Swift-Tuttle is large, with a nucleus of some 16 miles (26 km) in diameter. Comet Halley’s nucleus is half that and Churyumov–Gerasimenko’s nucleus that ESA’s Rosetta spacecraft is now orbiting is half Halley’s. Despite the wear and tear that a comet’s nucleus must endure when coming close to the Sun, the distribution of debris to give us a pretty even annual meteor shower means the comet has been near its present orbit for a very long time.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Addendum
Orbit of Comet 109P/Swift-Tuttle. Blue line is the comet’s orbit, coming from above. Credit NASA / JPL / Applet by Osamu Ajiki (AstroArts), and further modified by Ron Baalke (JPL)
Link to the animation from which the above image was taken and other information on Comet Swift-Tuttle go to http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=109P;cad=1
07/28/2014 – Ephemeris – One meteor shower is at peak and another is ramping up.
Ephemeris for Monday, July 28th. The sun rises at 6:24. It’ll be up for 14 hours and 48 minutes, setting at 9:12. The moon, 2 days past new, will set at 9:46 this evening.
We have a couple of meteor showers of note coming up. The first is the Southern Delta Aquarids which will peak on the 30th. The radiant point for these meteors will rise around midnight in the southeast. Their numbers and their brightness are not very great. The Perseid meteor shower will have the misfortune to coincide with the full moon on August 12th and 13th, drowning out all but the brightest meteors. However the Perseids have a long run up to their peak, so their numbers will grow after the moon sets until the moon sets in morning twilight. The Perseid radiant is circumpolar for Northern Michigan, meaning it never sets, so some Perseid meteors can always be seen at night. Their radiant will be in the northeastern sky in the evening.
Times are for the Traverse City/Interlochen area of Michigan. They may be different for your location.
Approximate Radiant of the South Delta Aquarid meteor shower. The radiant does move over the several weeks of the shower to the east. Created using my LookinUp program.
The Perseid meteor shower radiant a about 2 a,m, during the period of the shower. Created using my LookingUp program.
Bob Moler's Ephemeris Blog 