Posts Tagged ‘Eta Aquariids’

05/01/2017 – Ephemeris – Previewing May 2017 Skies

May 1, 2017 Comments off

Ephemeris for Monday, May 1st.  The Sun rises at 6:32.  It’ll be up for 14 hours and 15 minutes, setting at 8:47.  The Moon, 1 day before first quarter, will set at 2:24 tomorrow morning.

Today starts the month of May when the promise of spring is finally fulfilled.  Daylight hours in the Interlochen/Traverse City area will increase from 14 hours and 15 minutes today to 15 hours 19 minutes on the 31st.  The altitude, or angle, of the Sun above the southern horizon at local noon will ascend from 61 degrees now to 67 degrees at month’s end.  The altitude of the sun in the Straits area will be a degree lower than that but your daylight hours will be a few minutes longer.  Local apparent noon this month, when the sun passes due south, will be about 1:38 p.m.

This is the month of the Eta Aquariid meteor shower which will reach its peak this Thursday and Friday.  There will be dark skies around 5 a.m. to see the meteors coming from the southeast.

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


May Evening Star Chart

Star Chart for May 2017

Evening Star Chart for May 2017 (11 p.m. May 15, 2017). Created using my LookingUp program. Click on image to enlarge.

The planets and stars are plotted for the 15th at 11 p.m. EDT in the evening and 5 a.m. for the morning chart.  These are the chart times.  Note that Traverse City is located approximately 45 minutes behind our time meridian.  (An hour 45 minutes behind our daylight saving time meridian. during EDT and 45 minutes behind our daylight standard time meridian. during EST).  To duplicate the star positions on a planisphere you may have to set it to 1 hour 45 minutes (Daylight Time) or 45 minutes (Standard Time) earlier than the current time if you are near your time meridian.

Note the chart times of  11 p.m. and 5 a.m. are for the 15th.  For each week before the 15th add ½ hour.  For each week after the 15th subtract ½ hour.   The planet positions are updated each Wednesday on this blog.

May Morning Star Chart

Star Chart for May 2017 mornings

Star Chart for May 2017 mornings based on 5 a.m. May 15th. Created using my LookingUp program. Click on image to enlarge.

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
  • Follow the arc of the handle of the Big Dipper to the star Arcturus
  • The Summer Triangle is in red
  • The Eta Aquariid meteor shower radiant is in yellow and marked EAqR  is active from April 19th to May 28th and peaks May 6th.  Zenithal Hourly Rate at peak is expected to be 50, though considerably less than that is expected due to its radiant’s low position in our skies.  Data from the International Meteor Organization 2017 calendar.

Evening nautical twilight ends at 10:02 p.m. EDT on the 1st, increasing to 10:46 p.m. EDT on the 31st.
Evening astronomical twilight ends at 10:47 p.m. EDT on the 1st, increasing to 11:44 p.m. EDT on the 31st.
Morning astronomical twilight starts at 4:40 a.m. EDT on the 1st, and increasing to 3:44 a.m. EDT on the 31st.
Morning nautical twilight starts at 5:24 a.m. EDT on the 1st, and Increasing to 4:42 a.m. EDT on the 31st.

NASA Calendar of Planetary Events

Credit:  Sky Events Calendar by Fred Espenak and Sumit Dutta (NASA’s GSFC)
To generate your own calendar go to
Times are Eastern Time and follow the time change dates for Michigan, US

Date        Time    Event
May 01  Mo          Venus: 39.9° W
    02  Tu  2:23 pm Moon-Beehive: 3.7° N
    02  Tu 10:47 pm First Quarter
    04  Th  5:49 am Moon-Regulus: 0.6° N
    04  Th  6:42 am Moon Ascending Node
    04  Th 10:54 pm Eta Aquariid Shower: ZHR = 60
    05  Fr  9:51 am Mars-Aldebaran: 6.2° N
    07  Su  5:24 pm Moon-Jupiter: 2.3° S
    10  We  5:43 pm Full Moon
    12  Fr  3:51 pm Moon Apogee: 406200 km
    13  Sa  7:07 pm Moon-Saturn: 3.4° S
    14  Su  4:29 pm Moon South Dec.: 19.3° S
    17  We  6:59 pm Mercury Elongation: 25.8° W
    18  Th  8:33 pm Last Quarter
    18  Th  9:30 pm Moon Descending Node
    22  Mo  8:32 am Moon-Venus: 2.4° N
    23  Tu  9:20 pm Moon-Mercury: 1.6° N
    25  Th  3:44 pm New Moon
    25  Th  9:23 pm Moon Perigee: 357200 km
    27  Sa  7:36 pm Moon North Dec.: 19.4° N
    29  Mo  9:50 pm Moon-Beehive: 3.4° N
    31  We  7:56 am Moon Ascending Node
    31  We 12:08 pm Moon-Regulus: 0.3° N
Jun 01  Th          Venus: 45.8° W

May 2017 Calendar

LU                  Ephemeris of Sky Events for Interlochen/TC
May, 2017    Local time zone: EDT
|Mon  1| 06:32a  08:48p  14:15 | 10:00p  05:20a |      Set  02:24a   38%|
|Tue  2| 06:30a  08:49p  14:18 | 10:02p  05:18a |F Qtr Set  03:07a   49%|
|Wed  3| 06:29a  08:50p  14:21 | 10:03p  05:16a |      Set  03:43a   59%|
|Thu  4| 06:28a  08:51p  14:23 | 10:05p  05:15a |      Set  04:16a   70%|
|Fri  5| 06:26a  08:52p  14:26 | 10:06p  05:13a |      Set  04:45a   78%|
|Sat  6| 06:25a  08:54p  14:28 | 10:08p  05:11a |      Set  05:12a   86%|
|Sun  7| 06:24a  08:55p  14:31 | 10:09p  05:09a |      Set  05:39a   92%|
|Mon  8| 06:22a  08:56p  14:33 | 10:11p  05:08a |      Set  06:07a   97%|
|Tue  9| 06:21a  08:57p  14:36 | 10:13p  05:06a |      Set  06:36a   99%|
|Wed 10| 06:20a  08:58p  14:38 | 10:14p  05:04a |Full  Rise 08:45p  100%|
|Thu 11| 06:18a  09:00p  14:41 | 10:16p  05:03a |      Rise 09:42p   99%|
|Fri 12| 06:17a  09:01p  14:43 | 10:17p  05:01a |      Rise 10:38p   96%|
|Sat 13| 06:16a  09:02p  14:45 | 10:19p  05:00a |      Rise 11:30p   91%|
|Sun 14| 06:15a  09:03p  14:48 | 10:20p  04:58a |      Rise 12:19a   85%|
|Mon 15| 06:14a  09:04p  14:50 | 10:22p  04:57a |      Rise 01:03a   78%|
|Tue 16| 06:13a  09:05p  14:52 | 10:23p  04:55a |      Rise 01:44a   70%|
|Wed 17| 06:12a  09:06p  14:54 | 10:25p  04:54a |      Rise 02:21a   60%|
|Thu 18| 06:11a  09:08p  14:56 | 10:26p  04:52a |L Qtr Rise 02:54a   50%|
|Fri 19| 06:10a  09:09p  14:58 | 10:28p  04:51a |      Rise 03:26a   40%|
|Sat 20| 06:09a  09:10p  15:00 | 10:29p  04:50a |      Rise 03:57a   30%|
|Sun 21| 06:08a  09:11p  15:02 | 10:30p  04:48a |      Rise 04:28a   20%|
|Mon 22| 06:07a  09:12p  15:04 | 10:32p  04:47a |      Rise 05:02a   12%|
|Tue 23| 06:06a  09:13p  15:06 | 10:33p  04:46a |      Rise 05:38a    5%|
|Wed 24| 06:05a  09:14p  15:08 | 10:35p  04:45a |      Rise 06:20a    1%|
|Thu 25| 06:04a  09:15p  15:10 | 10:36p  04:44a |New   Set  09:04p    0%|
|Fri 26| 06:04a  09:16p  15:12 | 10:37p  04:42a |      Set  10:16p    2%|
|Sat 27| 06:03a  09:17p  15:13 | 10:39p  04:41a |      Set  11:21p    7%|
|Sun 28| 06:02a  09:18p  15:15 | 10:40p  04:40a |      Set  12:18a   15%|
|Mon 29| 06:02a  09:19p  15:17 | 10:41p  04:39a |      Set  01:05a   24%|
|Tue 30| 06:01a  09:19p  15:18 | 10:42p  04:38a |      Set  01:45a   34%|
|Wed 31| 06:00a  09:20p  15:19 | 10:43p  04:38a |      Set  02:19a   44%|
* Nautical Twilight
** Moonrise or moonset, whichever occurs between sunset and sunrise

05/03/2016 – Ephemeris – Halley’s Comet is back… In little bitty pieces

May 3, 2016 Comments off

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.


Eta Aquarid radiant

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.

05/05/2015 – Ephemeris – Eta Aquariids, an early visit of Halley’s Comet

May 5, 2015 Comments off

Ephemeris for Tuesday, May 5th.  Today the Sun will be up for 14 hours and 24 minutes, setting at 8:52.   The Moon, 2 days past full, will rise at 10:29 this evening.  Tomorrow the Sun will rise at 6:26.

The Eta Aquariid meteor shower will reach peak tomorrow morning.  But the Moon will be bright, so only the brightest of them will be seen.  However if you’re waiting to see the return of Halley’s Comet, you needn’t wait until the main body of the comet returns in 2061.  Halley’s Comet has made many passes of the inner solar system in recorded history, and many more before that, returning to the inner solar system every 76 years or so, before returning to its frigid home beyond Neptune.  It’s closest to the Sun, called perihelion is inside Venus’ orbit.  On the way in and out it passes close to the Earth’s orbit.  It has left a trail of debris, which we pass through in May and again in October.

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


Eta Aquarid radiant

The Eta Aquariid radiant at 5 a.m. The radiant moves slowly to the east with time. Credit:  My LookingUp program.

Halley's meteor shower

We get two meteor showers from Halley’s Comet. The Orionids, when Halley is approaching the inner solar system, and the Eta Aquariids when it’s leaving. Credit:  My LookingUp program.