October 2004 Skies

October marks the first full month of Autumn (Fall).  The SUN begins the month in the constellation VIRGO, which it entered in Mid-September.  The Sun will remain in VIRGO for more than 6 weeks, only entering the constellation LIBRA on October 29th. 

The Evening Sky:  Arizona sunsets occur about 6:05 p.m. In early October.  We should notice our Autumn evenings lengthening as Winter approaches, and that sunset occurs a bit later each day.  By month end Sunset will be at 5:30 p.m. 

The MOON begins the month of October four days past Full.  October’s New MOON occurs on the morning of the 14th in the constellation LEO.  On the next evening (10/15) a very thin “baby” crescent Moon may be seen low in the West about 30 to 35 minutes after sunset.  If you have a clear view down to the Western horizon, you should be able to spot this thin crescent Moon even without binoculars.  October’s Full Moon is special – it features a widely visible TOTAL LUNAR ECLIPSE.  The eclipse happens in the zodiac constellation of ARIES very shortly after sunset on the evening of the 27th.  A more detailed account of the Lunar Eclipse is available elsewhere on the EV Living Astronomy website.

We begin the month of October with NO evening naked-eye planets.  However, first Mercury and then Saturn join the evening sky by month end.  On October 4th, Mercury moves Eastward past the Sun into the evening sky.  Each following evening in October, Mercury will set later than the Sun, and Mercury quickly moves into the constellation of LIBRA on October 20th.  By October 31st, Mercury is still moving Eastward away from the Sun, and sets about 45 minutes after sunset.  However, look for elusive Mercury to be even more visible on early November evenings.

On October 12th, Saturn again becomes an Evening Planet, having been in our morning sky since early July.  Saturn, found in the Winter constellation of GEMINI, rises four minutes earlier each evening.  By month end, the planet rises at 10:40p.m., and still resides in Gemini.

The Morning Sky:  Early October sunrises occur shortly after 6:25a.m. but the sun will not rise until about 6:50a.m. on November 1st.  Look for the waning MOON to be visible in early October morning skies.  On the mornings of October 2nd and 3rd it passes near the Pleiades star cluster in the constellation TAURUS.  The morning of October 7th you will see the Moon rise only 3 degrees away from the bright star POLLUX and within 8 degrees of planet Saturn.  Three days later, on October 10th, a thin crescent Moon is only 5 degrees away from the bright planet VENUS.  On the 12th a VERY thin crescent Moon rises 15 minutes before JUPITER low in the Eastern sky. 

Look for VENUS to rise a few minutes after 3:00a.m. in the constellation LEO on the 1st, but Venus will rise 50 minutes later by month end, when it has moved into VIRGO.  JUPITER begins the month too close to the Sun to be visible, but on the 31st, will rise at 4:18 a.m. in a dark sky –less than 25 minutes after Venus.  MARS is also very close to the Sun on October 1st, but by November may be seen by sharp-eyed observers low in the East 30 to 40 minutes before sunrise.  Both Mars and Jupiter remain in Virgo all month.

What Else to See?  Several close Moon-Planet positionings (or conjunctions) are listed above.  However, observers with small telescopes can watch the Moon occult (pass in front of) stars of 6th magnitude or brighter on the mornings of October 4th, 10th, 26th, 29th, and 30th and on the evenings of October 1st, 2nd, 4th, 18th, 22nd, 25th, 26th, 28th, 29th and the 31st.

A Partial Solar Eclipse occurs after sunset on October 12th, but is not visible from Arizona.  It will be seen from Hawaii, Alaska, the Western Pacific Ocean and Eastern Asia.  Even though partial solar eclipses are of limited astronomical interest, this eclipse may be broadcast over the internet.  Use an Internet search engine to try to locate sites hosting a live eclipse broadcast.

October is the last month for convenient viewing of the summer zodiac & Milky Way constellations of SCORPIO and SAGITTARIUS.  These stars will set earlier each evening until too low in the Southwest to be observed by month-end.  However, the rest of the summer Milky Way is still high overhead in October.  The Moon rises later each evening (after 10p.m. on the 4th, and after midnight on the 7th), so there should be plenty of dark October evenings for continued viewing of the late-Summer sky. 

With binoculars or a small telescope you can observe many interesting objects scattered along the Winter Milky Way, which is starting to become visible in the Eastern sky.  Look for the Pleiades star cluster to rise shortly after 8p.m. on the 1st (2 hours earlier on the 31st).  Also interesting are the star-rich Winter Milky Way Constellations of CASSIOPEIA, PERSEUS, (includes the famous “Double Cluster”), AURIGA and GEMINI.  Look for CASSIOPEIA and PERSEUS low in the East at 8p.m. on October 1st, while AURIGA and GEMINI will rise by 10p.m. on October 15th. 

On Friday evening, October 8th,  the East Valley Astronomy Club will host a Free Public Star Party at the Riparian Preserve next door to the Gilbert Public Library.  Several telescopes will be set up for viewing many interesting astronomical objects.  The Club will also sponsor an astronomy lecture at 8:00 p.m. inside the Library.  Admission to the lecture is $3.

EVAC also plans to hold a public Lunar Eclipse Viewing Party at the Riparian Preserve the evening of October 27th.  Arrive by 6p.m. to view the entire eclipse!

Good Luck Observing!