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Astronomy a Go Go! September Sky Tour



This tool displays the approximate Moon phases for a given month(images are close approximations). For official phase times and dates for this month and past months are available from the U.S. Naval Observatory.

Astronomical Online Glossary

Download this month's sky map!

Skymaps.com is our favorite monthly skymap provider. Download either the Northern hemisphere, Equatorial, or Southern Hemisphere sky map so you can follow along with our viewing sessions.
Creator: Kym Thalassoudis

 

Southern Hemisphere Additional Information

As Astronomy a Go Go! finds its home in the higher Northern latitudes those of you who live south of the equator will benefit from these two Southern Hemisphere sites: Royal Astronomical Society of New Zealand's Southern Hemisphere Calendar RASNZ site (absolutely outstanding) and
Southern Sky Watch.

 

Great Astronomy Activities!

Citizen Sky

For those in Northern Hemisphere, Capella, the "She Goat" in Aurigae, is circumpolar. At my 47 deg North, Capella disappears behind the tree line, and into the light polluted horizon, but she pops up in a few hours and is easy to find. Also easy to find are epsilon Aurigae (al Maaz the Billy Goat) and "The Kids" which make a small, long, triangle of stars just to the Southwest of Capella.

For the next 21 months Epsilon Aurigae, usually the brightest of the trio, will start behaving quite differently than it has for the past 27 years. Epsilon Aurigae is a type of variable star called an eclipsing binary. Epsilon Aurigae and some unknown dark partner, rotate around a common center of mass and every 27 years that dark companion eclipses the giant F-type star. August marks the anticipated beginning for that eclipse which will last for 714 days, dimming from 3.0 mag to about half of its brightness.

So why am I calling this a great astronomy activity? Epsilon Aurigae has some definite quirks and more eyes are needed to help scientist figure out what Epsilon Aurigae's invisible partner really is! We need help...WE NEED YOU!! Anyone can participate; we need people to observe epsilon Aurigae, folks to look at the data for quirks, patterns, or voids, artist to help present the data to the public, friends willing to get the word out to others! To find out more visit:

NASA's MicroObservatories

Another fantastic project, that AAGG is supporting all through the month of September, it the "Capture the Colorful Cosmos" project using the NASA MicroObservatories. This project gives you the opportunity to direct a robotic telescope and then manipulate the resulting images!

I had the opportunity to help school age kids, and some kid-like adults, through the project at the Tacoma Astronomical Society's annual Astronomy Fair in August and we had a wonderful time! They were using filter, shifting and stacking images, and turning out images like the pros!


Sweet and innocent "A", and the postcard of M51 he created (Blasters of Death -- go figure), and his sister's Orion composite image (ahhhhhh!)

LCROSS Impact

Astronomers, amateur and professional a like, who have access to dark skies and large aperture scopes are encouraged to participate in imaging and video taping the impact of the Centaur impactor and the LCROSS satellite with the Moon. The primary objective of the Lunar Crater Observation and Sensing Satellite (LCROSS) is to confirm the presence or absence of water ice in the Moon's polar region. But the amazing bit will be the five body choreography between the Moon, the Centaur rocket/impactor, the Shepherding craft/research vessel/impactor, and LRO (who was launched with LCROSS) who will also observe the action, and YOU, on Earth!

I mean... what other impactor mission has its own music video!

More information can be found at the LCROSS Citizen Observing Campaign Site.


Images courtesy of: New Mexico State Univ

Planets for September 2009

September Morning Planets
(click images to enlarge)

 


Beginning of the month


End of the month

  • Mercury- Starts September headed for the Sun in the early evening sky, best observed by lower and southern latitudes. By the end of the month Mercury will join Venus, Mars, and Saturn in the morning sky. 0.5 mag (1st) to 5.5 mag (21st)
  • Venus- Beautiful in the morning sky and is heading eastward towards Regulus. Venus will be half a degree north of Regulus on the 20th of the month as she heads back towards the Sun. She will pair up with Mercury and Saturn in the early October sky so make sure you spend some time pre-sunrise time around the 5th of October with Venus and Saturn making a Mercury breakfast sandwich! -3.8 mag (1st) to -3.8 mag (21st)
  • Mars- Spends the month in Gemini so you'll need to get up early for this one too! 1.00 (1st) to 0.9 mag (21st)
  • Jupiter- AAGG missed Jupiter's vanishing moons due to bad weather but John Chumack, of The Chumack Observatories, captured the event and has a movie posted at his site! -2.8 mag (1st) to -2.7 mag (21st)
  • Saturn- In conjunction with the Sun on the 17th, moving into the morning sky. Look for the return of Saturn in October. 1.1 mag (1st) to 1.1 mag (21st)
  • Uranus- At opposition in Pisces on the 17th. 5.7 mag (1st) to 5.7 mag (21st)
  • Neptune- In Capricorn 7.8 mag (1st) to 7.8 mag (21st)
  • Ceresand Eta - Finder chart from the New Zealand RAS (RASNZ) great charts! Northern Hemisphere observers this time you get to flip the chart or stand on your head!
    Vesta chart temporarily missing...use this one until site is corrected

Key Dates for September 2009

Days and Times in UT: (help with time)
Observations are for 10 pm for Northern Hemisphere and 8pm for the Southern Hemisphere.
Today's sunrise and sunset times or plan ahead using the US Naval Observatory Website

Occultation information can be found at the IOTA website!

Astronomical Highlights - September 2009

1 - Venus 1.2 deg SSW of Beehive cluster (M44) early morning sky
2 - Moon near Jupiter in the evening sky
2-3 - Jupiter's moons line up in front of and behind Jupiter such that Jupiter has no moons. See www.spaceweather.com for more details
4 - Full Moon 16:03 UT
- Saturn's rings edge on as seen from Earth
6 - Mercury stationary beginning retrograde motion
9 - September Perseids
10 - Moon near Pleiades in the morning sky
9-16 - Astronomy A Go Go! at the Afterschool Universe training, the AANC Annual Meeting, and the ASP conference in San Francisco!
12 - Last Quarter Moon
13 - Moon very near Mars in the morning sky possible occultation check the IOTA website for more information
15 - Moon near Beehive cluster (m44) in the morning sky
16 - Moon at perigee (closest to Earth) 364,053km)
- Zodiacal Lights vis in N latitudes before sunrise in the East next two weeks (example image, the reflection of sunlight off interplanetary dust in the plane of the ecliptic)
17 - Moon near Regulus
- Saturn in conjunction with the Sun moving into the morning sky
- Uranus at opposition
18 - New Moon at 18:44 UT
20 - Mercury at inferior conjunction with the Sun as it moves into the morning sky
- Venus 1/2 degree NNE from Regulus
- Moon near Spica
22 - September equinox 21:22 UT Point in the year where the Sun passes along the ecliptic into the Southern Hemisphere
24 - Moon near Antares in the evening sky possible occultation check the IOTA website for more information
26 - First Quarter Moon
28 - Moon at apogee (furtherest from the Earth) 404,432
29 - Moon near Jupiter in the evening sky
October
4 - Full Moon
16 - In the pre-dawn sky; Arcturus is to the north, the crescent Moon to the south, and stacked in between, from the horizon, Mercury, Venus, and Saturn.

Date information courtesy of: RASC Observer's Handbook, Skymaps.com, Astronomical Calendar 2009, CalSky, Skymaps.com. sunrise and sunset times for your home*
Comparative lengths of day and night

    Monthly Messier*

    This month our monthly Messier hits some big easy targets, eight more globular clusters, all are possible in binoculars, and two of these are the finest globulars which can be seen from northern locations.

    Sagittarius is the home of many globular clusters which surround the center of the Milky Way Galaxy. Seven of the these globulars appear in the Messier catalog, we will be visiting five of them this month. When you complete the search for these objects be sure to spend some time scanning this region with binoculars or a telescope and see what other sights you can discover. I guarantee you will not be disappointed.

    • M13 - The great globular cluster in Hercules is bright enough to be seen with naked eye and typically the first GC found by amateur astronomers in the NH. Binoculars easily show this cluster as a bright fuzzy ball. M13 is partially resolvable in small aperture telescopes and becomes a fantastic swarm of tightly packed individual stars through large scopes.
    • M92 - Another globular cluster in Hercules, M92 is easy to find in binoculars appearing slightly dimmer and smaller than M13. As with M13 it is partially resolvable in small scopes and is a fine sight in large instruments.
    • M14 - A small, bright globular cluster in Ophiuchus. It is a difficult binocular object, look for a small fuzzy patch of light. Through a telescope M14 is an even patch of light, the stars not resolvable except through large scopes.
    • M22 - This is the other great globular in our tour this month. Located just above the teapot asterism in Sagittarius, M22 can be seen with no optical aid. M22 is easy to find in binoculars, and easy to resolve in telescopes, with about the same impressiveness as M13.
    • M28 - Located near M22 in Sagittarius, this is a small bright globular. A tough binocular object, look for a small fuzzy patch. Easily seen in a telescope, but requires large aperture to resolve individual stars.
    • M69, M70, M54 All of these are small bright globular clusters laying along the bottom of the teapot in Sagittarius. Very similar in appearance to M28, these are all tough binocular objects requiring dark skies and possibly averted vision to see. M54 is slightly brighter and appears more star like through binoculars than the other globulars. These are all easily seen in telescopes, though not easily resolvable.

    From the Astronomical Connection and the Moncton Center in Canada

    From the Tony Cecce, Corning, NY - Twelve Month Tour of The Messier Catalog

    Comets for September 2009

    More comet information at Seiichi Yoshida's comet website. Also checkout Gary Kronk's comet and meteor pages
    Skyhound Comet pages

    Historical and Current Events

    ...Did you know?

    Mark has developed his own website so let's all trot on over and see the pages of wonderful history he has for us this month!

    Help us out by leaving a donation in the ol' PayPal hat

    or write us a favorable review in iTunes of Podcast Pickle or iPodder!

     

    Music Scottish Guitar Quartet -"Romance Within You"
    Black Lab- "See the Sun"
    Anne Farnsworth- "Saturday Morning"

     



    Earth's major motions for 2009

    Perihelion
    Jan 4 15(UT)
    First Cross Quarter Day
    Feb 2-6
    Equinox
    Mar 20 11:44(UT)
    Second Cross Quarter Day
    May 4-7
    Solstice
    June 21 05:45(UT)
    Aphelion
    July 4 02h (UT)
    Third Cross Quarter Day
    Aug 5-8
    Equinox
    Sept 22 21:18(UT)
    Fourth Cross Quarter Day
    Nov 5-8
    Solstice
    Dec 21 17:47(UT)

    Planet Positions for 2009


    2009 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
    Venus Sgr Cap Aqr Psc Tau Gem Cnc Vir Vir Sco Sgr Cap
    Mars Sgr Cap Aqr Psc Psc Ari Tau Tau Gem Cnc Cnc Leo
    Jupiter Cap Cap Cap Cap Cap Cap Cap Cap Cap Cap Cap Cap
    Saturn Leo Leo Leo Leo Leo Leo Leo Leo Vir Vir Vir Vir

     

    Interesting Planet Pairing for 2009

    • December 31, 2008 - Jupiter and Mercury - After sunset a little more than one degree apart in Sagittarius. Pull out the binos and telescopes because Mercury will be a mere 15 arcminutes from the globular cluster M75. All three will be together in one field of view in most home binoculars.
    • January 22nd - Venus and Uranus - After sunset 1.3 degrees apart a few days later on the 29th they are joined by a waxing crescent moon.
    • February 23rd - Jupiter, Mars and Mercury - In the early morning sky just before sunrise the trio are in a space about 2 degrees wide. Binoculars will be helpful but beware the quickly rising Sun. The Moon, almost invisible, will be between Mars and the Sun.
    • March 23rd - Mars, Moon, Neptune, and Jupiter - Makes a nice line-up in the morning sky with Neptune just off the tip of the waning crescent moon.
    • April 21st - Venus, Mars, Uranus, waning crescent Moon, Neptune and Jupiter - all in the pre-dawn sky together. First the right triangle of Venus, Mars, and Uranus followed by the waning crescent Moon and then finally by Neptune and Jupiter. Mars will be a faint 1.41 mag so binoculars will be helpful. The next day, possible occultation of Venus by the Moon. Check the IOTA website for occultations in your area.
    • May 25th - Jupiter and Neptune - Jupiter is less than 1/2 degree South of Neptune in the morning sky. If you have ever had problems finding Neptune this would be a good time to try, between now and June.
    • June 19th - Venus and Mars - In the pre-dawn sky just south of a waning crescent Moon. Closer to the Sun is Mercury and the Pleiades.
    • August 17th - Saturn and Mercury - Very close to the Sun low in the evening sky. Much better view for Southern viewers.
    • September 3rd UT 4:43 - Jupiter hides its Galilean moons. Not until 2019 will all of Jupiter's Galilean moons orbit in such a way.
    • September 4th - Saturn - Not exactly a pairing but the Earth will cross the plane of the rings from south to north making the rings invisible
    • October 16th - Mercury, Venus, and Saturn - All lined up in the pre-dawn sky close to the horizon. A faint waning crescent is just south of the trio.
    • December 24th - Jupiter and Neptune - Just after sunset Jupiter and Neptune sit side-by-side just north of delta Capricornus and east of the "42,44,45 Cap Wall"

    Phases of the Moon 2009


    (click to enlarge)

    Universal Time

          NEW MOON    FIRST QUARTER       FULL MOON     LAST QUARTER
    
           d  h  m          d  h  m         d  h  m          d  h  m
           
                     JAN.   4 11 56   JAN. 11  3 27   JAN.  18  2 46
    JAN.  26  7 55   FEB.   2 23 13   FEB.  9 14 49   FEB.  16 21 37
    FEB.  25  1 35   MAR.   4  7 46   MAR. 11  2 38   MAR.  18 17 47 
    MAR.  26 16 06   APR.   2 14 34   APR.  9 14 56   APR.  17 13 36  
    APR.  25  3 23   MAY    1 20 44   MAY   9  4 01   MAY   17  7 26
    MAY   24 12 11   MAY   31  3 22   JUNE  7 18 12   JUNE  15 22 15
    JUNE  22 19 35   JUNE  29 11 28   JULY  7  9 21   JULY  15  9 53  
    JULY  22  2 35   JULY  28 22 00   AUG.  6  0 55   AUG.  13 18 55  
    AUG.  20 10 02   AUG.  27 11 42   SEPT. 4 16 03   SEPT. 12  2 16
    SEPT. 18 18 44   SEPT. 26  4 50   OCT.  4  6 10   OCT.  11  8 56  
    OCT.  18  5 33   OCT.  26  0 42   NOV.  2 19 14   NOV.   9 15 56  
    NOV.  16 19 14   NOV.  24 21 39   DEC.  2  7 30   DEC.   9  0 13  
    DEC.  16 12 02   DEC.  24 17 36   DEC. 31 19 13
    
    

    Eclipses for 2009

     

    2009 January 26
    [ Solar: Annular ]
    2009 February 09
    [ Lunar: Penumbral ]
    2009 July 07
    [ Lunar: Penumbral ]
    2009 July 21-22
    [ Solar: Total ]
    2009 August 05-06
    [ Lunar: Penumbral ]
    2009 December 31
    [ Lunar: Penumbral ]

     

    January 26 - Annular Solar Eclipse ( see map, times, and animation!): The first solar eclipse of 2009 occurs at the Moon's ascending node in western Capricornus. An annular eclipse will be visible from a wide track that traverses the Indian Ocean and western Indonesia. A partial eclipse will be seen within the much larger path of the Moon's penumbral shadow, which includes the southern third of Africa, Madagascar, Australia except Tasmania, southeast India, Southeast Asia and Indonesia.

     

    February 09 - Penumbral Lunar Eclipse ( see map, times): The first lunar eclipse of 2009 is one of four such events during the year. The first three eclipses are penumbral while the last (on Dec. 31) is partial. The Feb 09 event is the deepest penumbral eclipse of the year with a penumbral magnitude of 0.899. It will be easily visible to the naked eye as a dusky shading in the northern half of the Moon. The times of the major phases are listed below.

    July 07 - Penumbral Lunar Eclipse ( see map, times.): July's penumbral eclipse is only of academic interest since the magnitude is just 0.156. Although the Moon will be above the horizon from most of Canada, the eclipse is so minor as to be completely invisible to the naked eye.

    July 21-22 - Total Solar Eclipse ( see map, times, and animation!): To make up for the anemic lunar eclipse earlier in the month, a major total eclipse of the Sun occurs two weeks later. The path of the Moon's umbral shadow extends across India, China, a handful of Japanese islands and the South Pacific Ocean (Espenak and Anderson, 2008). A partial eclipse is seen within the much broader path of the Moon's penumbral shadow, which includes most of eastern Asia, Indonesia, and the Pacific Ocean.

    August 05-06 - Penumbral Lunar Eclipse ( see map, times): A shallow penumbral eclipse occurs 15 days after the total solar eclipse. Since its magnitude is only 0.402, it will not be visible to the naked eye.

    December 31 - Penumbral Lunar Eclipse ( see map, times): The last eclipse of 2009 occurs on New Year's Eve. This minor partial lunar eclipse takes place in Gemini, and is visible primarily from the Eastern Hemisphere (Figure 8). Greatest eclipse takes place at 19:23 UT when the eclipse magnitude will reach 0.0763.

    Eclipse information from: NASA Eclipse Homepage, Eclipses Online (HM Nautical Almanac Office, UK in coordination with the U.S. Naval Observatory)

    2009 Meteor Shower Calendar

    Shower Activity Period Maximum Radiant Velocity r ZHR Class Moon
        Date S. L. R.A. Dec. km/s        
    Antihelion Source (ANT) Dec 14-Sep 07 - - - - 30 3.0 3 II -
    Quadrantids (QUA) Dec 26-Jan 13 Jan 03 283°16 15:20 +49° 42 2.1 120 I 6
    Alpha Centaurids (ACE) Jan 28-Feb 21 Feb 07 319°2 14:00 -59° 56 2.0 5 II 12
    Delta Leonids (DLE) Feb 15-Mar 10 Feb 25 336° 11:12 +16° 23 3.0 2 II 0
    Gamma Normids (GNO) Feb 25-Mar 22 Mar 13 353° 16:36 -51° 56 2.4 4 II 16
    Lyrids (LYR) Apr 16-Apr 27 Apr 23 033° 18:12 +33° 46 2.1 18 I 27
    Pi Puppids (PPU) Apr 15-Apr 28 Apr 23 033°5 07:20 -45° 18 2.0 var III 27
    Eta Aquarids (ETA) Apr 27-May 23 May 07 047° 22:36 -01° 68 2.4 60 I 12
    Eta Lyrids (ELY) May 06-May 14 May 10 050° 19:22 +43° 43 3.0 3 II 15
    June Bootids (JBO) Jun 22-Jul 02 Jun 27 095°7 14:56 +48° 18 2.2 var III 5
    Piscis Austrinids (PAU) Jul 15-Aug 10 Jul 28 125° 22:44 -30° 35 3.2 5 II 7
    Alpha Capricornids (CAP) Jul 12-Aug 08 Jul 28 125° 20:20 -10° 24 2.5 4 II 7
    Delta Aquarids (SDA) Jul 21-Aug 30 Jul 30 127° 22:42 -17° 43 3.2 20 I 9
    Perseids (PER) Jul 13-Aug 26 Aug 12 140° 03:12 +58° 59 2.6 100 I 20
    Kappa Cygnids (KCG) Aug 03-Aug 25 Aug 17 145° 19:04 +59° 25 3.0 3 II 25
    Alpha Aurigids (AUR) Aug 28-Sep 03 Sep 01 158°6 06:06 +39° 65 2.6 7 II 11
    September Perseids (SPR) Sep 06-Sep 13 Sep 10 168° 03:12 +40° 65 2.9 5 II 19
    Delta Aurigids (DAU) Sep 18-Oct 10 Sep 29 186° 05:52 +49° 64 2.9 2 II 13
    Draconids (GIA) Oct 06-Oct 10 Oct 08 195°4 17:28 +54° 20 2.6 var III 18
    Southern Taurids (STA) Sep 18-Nov 26 Oct 11 198° 02:18 +09° 29 2.3 5 II 21
    Epsilon Geminids (EGE) Oct 18-Oct 21 Oct 20 207° 06:48 +28° 71 3.0 2 II 2
    Orionids (ORI) Sep 28-Nov 10 Oct 21 208° 06:22 +16° 68 2.5 23 I 3
    Leo Minorids (LMI) Oct 17-Oct 27 Oct 23 209° 10:40 +37° 61 2.7 2 II 4
    Northern Taurids (NTA) Oct 20-Nov 29 Nov 13 231° 03:52 +22° 29 2.3 5 II 25
    Leonids (LEO) Nov 07-Nov 28 Nov 18 236° 10:16 +22° 71 2.5 var III 1
    Alpha Monocerotids (AMO) Nov 15-Nov 25 Nov 21 239°32 07:48 +01° 65 2.4 var III 4
    Dec Phoenicids (PHO) Nov 28-Dec 09 Dec 06 254°25 01:12 -53° 18 2.8 var III 18
    Puppid/Velids (PUP) Dec 01-Dec 15 Dec 07 255° 08:12 -45° 40 2.9 10 I 19
    Monocerotids (MON) Dec 06-Dec 20 Dec 07 255° 06:32 +09° 41 3.0 2 II 10
    Sigma Hydrids (HYD) Nov 22-Dec 23 Dec 09 257° 08:24 +03° 60 3.0 3 II 21
    Geminids (GEM) Dec 05-Dec 19 Dec 14 262°2 07:36 +32° 35 2.6 120 I 26
    Coma Berenicids (COM) Dec 10-Jan 25 Dec 19 268° 11:40 +25° 64 3.0 5 II 3
    Ursids (URS) Dec 16-Dec 25 Dec 22 270°7 14:34 +75° 32 3.0 10 I 5

    Information and Table Template Courtesy The American Meteor Society, International Meteor Organization, and Meteors Online.

    Explanation of the 2009 Meteor Shower Calendar

    Shower: named for the constellation or closest star within a constellation where the radiant is located at maximum activity.

    Activity Period: the dates when the ZHR (Zenith Hourly Rates) are equal to or greater than one.

    Maximum: the date on which the maximum activity is expected to occur.

    S.L.: the equivalent solar longitude of the date of maximum activity. Solar longitude is measured in degrees (0-359) with 0 occurring at the exact moment of the spring equinox, 90 at the summer solstice, 180 at the autumnal equinox, and 270 at the winter solstice.

    Radiant: the area in the sky where shower meteors seem to appear from. This position is given in right ascension (celestial longitude) and declination (celestial latitude).

    Velocity: the velocity at which shower meteors strike the Earth's atmosphere. The velocity depends on the angle meteoroids (meteors in space) intersect the Earth. Meteoroids orbiting in the opposite direction of the Earth and striking the atmosphere head-on are much faster than those orbiting in the same direction as the Earth. This velocity is measured in kilometers per second.

    r: The Population Index, An estimate of the ratio of the number of meteors in subsequent magnitude classes. Simply stated: the lower the "r" value, the resulting overall mean magnitude of each shower will be brighter. "r" usually ranges from 2.0 (bright) to 3.5 (faint).

    ZHR: Zenith Hourly Rate, the average maximum number of shower meteors visible per hour if the radiant is located exactly overhead and the limiting magnitude equals +6.5. Actual counts rarely reach this figure as the zenith angle of the radiant is usually less and the limiting magnitude is usually lower. ZHR is a useful tool when comparing the actual observed rates between individual observers as it sets observing conditions for all to the same standards.

    Class: A scale developed by Robert Lunsford to group meteor showers by their intensity:

    Class I: the strongest annual showers with ZHR's normally ten or better.

    Class II: reliable minor showers with ZHR's normally three or better.

    Class III: showers with widely variable rates. They may be strong one year and totally inactive the next.

    Class IV: weak minor showers with ZHR's rarely exceeding three. The study of these showers is best left to experienced observers who use plotting and angular velocity estimates to determine shower association. Observers with less experience are urged to limit their shower associations to showers with a rating of I to III. These showers are also good targets for video and photographic work.

    Moon: the age of the moon in days where 0 is new, 7 is first quarter, 14 is full, and 21 is last quarter. Meteor activity is best seen in the absence of moonlight so showers reaching maximum activity when the moon is less than 10 days old or more than 25 are much more favorably observed than those situated closer to the full moon.

    Information from the "Observer's Handbook 2009" RASC



    Direct download: AAGG_sky_tour_Sept_09.mp3
    Category:Sky Tours -- posted at: 8:46 AM