OCTOBER 2012 NIGHT SKY CALENDAR
For all the poetic descriptions people use for October, for us it is merely the "End of the Denial." When September begins, we can insist that, astronomically, autumn won’t arrive until the autumnal equinox. Just after the equinox, we can argue that "Yeah, well, ok, maybe autumn has commenced, but, really, autumn is in its infancy and it feels a lot like summer…" When October arrives, we exhaust our denial reservoir and are compelled to concede that, well, autumn is here, sort of. And, it is not as though we dislike autumn. Hardly. We just have a preferance for heat over chill. For instance, you can still like chocolate, but if you were abducted by an alien who gave you a choice between chocolate and oxygen, you could still choose the latter withouth harboring any distaste for the former.
Now that we've sorted that matter out, we can proceed rapidly to the October Night Sky Calendar. For those who just arrived: space-time issues preclude us from including every single noteworthy astronomy event. (In other words, we lack the space to include all the items, and the time to write them.) So, we choose the most prominent events and just hope for clear skies to see them.
Also, look for [planetarium events] inappropriately inserted into the calendar.
WEDNESDAY, OCTOBER 3
VENUS 0.15 DEGREES SW OF REGULUS
The apparent close approach of one celestial object to another is called an "APPULSE." Tonight, we'll see the closest appulse of a planet and a bright star (first magnitude) for the year. One can see Regulus, Leo's alpha star, and Venus low in the eastern pre-dawn sky. Distinguishing between the planet and star will be quite easy as Venus is 144 times brighter than Regulus.
THURSDAY, OCTOBER 4
We have to be careful about terms. At times, a celestial event seems to contradict physical reality . To read the header one would think that Jupiter had come to a cold stop in its orbit. We know that, like the wicked, planets do not rest. They have revolved around the Sun in the same direction since their formation. The phrase "Jupiter Stationary" means that Jupiter will appear to stop in its orbit and change directions. Jupiter's motion has been prograde (eastward), but after today will begin a retrograde (westward) loop. [Refer to the Jupiter section of the 'Planet Watch' for more information on how to observe this loop.] This apparent backward motion results from Earth's motion. Our planet is now catching up to Jupiter and will pass it (when Jupiter's at opposition) on December 2nd. As Earth approaches and passes Jupiter, the latter world will appear to reverse course relative to background stars. So, Jupiter won't be stationary, but will merely appear that way.
FRIDAY, OCTOBER 5
MOON 1.1 DEGREES SE OF JUPITER
We will see brilliant Jupiter and the gibbous moon travel together throughout the night. If one experiences difficulty identifying Jupiter, one need only look next to the moon this evening. Obsevers in southern Australia will see the moon move in front of Jupiter, an event called an "occultation."
WEDNESDAY, OCTOBER 10
[ Midnight Metaphysical Society meeting 7:00 p.m.]
LAST QUARTER MOON
THURSDAY, OCTOBER 11
[ Night Sky Mythology Course begins: 7:00 p.m.]
FRIDAY, OCTOBER 12
MOON 5.9 DEGREES SSW OF VENUS
What else could one want in the sky: rose-tinctured eastern horizon; crescent moon and the bright planet Venus. If you are going to choose any morning this month to observe the sky before sunrise, choose October 12. Provided the sky is clear, you'll see the splendid coupling of Venus and the moon.
MONDAY, OCTOBER 15
Beginning of lunation cycle 1111.
[The Stone Circle Society meeting 7:00 p.m.]
TUESDAY, OCTOBER 16
MOON 1.4 DEGREES NNW OF MERCURY
This planet-moon encounter won't be as spectacular as the moon-Venus event on October 12th. Find the thin crescent moon and Mercury low in the western evening sky just after sunset.
[SCIENCE LECTURE: Investigating Earth from Space 7:00 p.m.]
THURSDAY, OCTOBER 18
MOON 2.1 DEGREES NNE OF MARS
The Moon will appear larger than it did on the 16th and will be higher in the western evening sky after sunset. Mars is the dimmest planet and therefore hardest to find. However, you'll have an easier time finding Mars tonight as it will appear close to the night sky's most conspicuous object.
SUNDAY, OCTOBER 21
ORIONID METEOR SHOWER PEAKS (PICK EVENT!)
We're generally reluctant to designate a meteor shower as a peak event because sometimes meteor showers that seemed promising end up being crashing bores. Conversely, when we tell you that Venus will be 5.9 degrees north-north-east of the Moon, you can be well assured that you'll see the moon and planet so configured. (Celestial mechanics is real silver magic.) Meteor showers occur when Earth passes through a cometary particle stream, so meteor frequency calculations involve a measure of uncertainty. We hope that this year's Orionid shower will be quite active, producing 30 - 50 meteors an hour on peak night. We love the Orionid shower for two reasons: one, the meteors appear to emanate out of Orion, hence the name. Secondly, the parent comet is none other than Halley's Comet, itself, due to return to the inner solar system in 2061. Though many won't see the comet return, we can still see its fragments burning up in the sky.
MONDAY, OCTOBER 22
FIRST QUARTER MOON
THURSDAY, OCTOBER 25
SATURN IN SOLAR CONJUNCTION
If you were "above" the solar system today, you would see Earth, the Sun, and Saturn in a straight line with the planets on either side of the Sun. Any observer on the Sun would see the two planets in opposite parts of the sky and therefore one could also consider Earth and Saturn to be in heliocentric opposition.
FRIDAY, OCTOBER 26
MERCURY AT GREATEST EASTERN ELONGATION (24.1 DEGREES FROM THE SUN)
So, just remember the counter-intuitive statement "When an inferior planet is at greatest eastern elongation, one could find it in the western evening sky," or "When an inferior planet is at greatest western elongation, one could find it in the eastern pre-dawn sky." Find Mercury tonight in the early evening western sky. After today, it appears to retreat back toward the Sun. Despite being at elongation, it's still an a low angle for us and therefore not easy to observe.
[THE GHOST HOUR 8:00 - 9:00 p.m.]
MONDAY, OCTOBER 29
The October full moon is not always called the "Harvest Moon," defined as the closest full moon to the Autumnal Equinox. This year, we had the Harvest Moon on September 29. The other common term for October's full moon is the "Hunter's Moon," as hunters pursue their prey in the autumn. The full moon's illumination helps the hunter see the prey, but, of course, can also help the prey spot and stay the devil away from the hunter.
TUESDAY, OCTOBER 30
SUN ENTERS LIBRA THE SCALES
The Sun doesn't move into different constellations. Earth revolves around the Sun once a year and from our perspective, the Sun appears to progress through thirteen constellations. The Sun has been in Virgo the maiden since September 16th and will remain Libra the Scales until November 22, when it enters Scorpius the Scorpion.
October is not Mercury's month. Of course, it is technically visible all month low in the western evening sky, and remains as bright as Arcturus throughout October, but remains frustratingly close to the Sun until the 3rd and 4th week. VERDICT: Best time to find Mercury is late this month. Look toward the western sky soon after sunset.
Venus is ALWAYS brighter than any other planet. It always will be, of course, unless Jupiter goes supernova. (For the benefit of the astrophysicists who just spurted out their Red Bull, Jupiter can NEVER go supernova. Only highly massive stars do that.) So, when we tell you that Venus' brightness gradually diminishes throughout the month, just ignore us. Venus remains more than 10 times brighter than Sirius, the night sky's brightest star, all month. VERDICT: Venus is a splendid early morning sight all month. Beautiful sight for joggers, cyclists and insomniacs.
Mars remains visible for the rest of the year, but will also be dimmer than the other visible planets (Mercury, Venus, Jupiter and Saturn) for the rest of 2012 as well. See Mars in the western evening sky. It is higher than Mercury and consequently easier to find. VERDICT: Though dim, Mars retains a ruddy red hue, making it more distinguishable than it might otherwise be. It's not a spectacle, but it is still easy to find if you're out early enough.
JUPITER (PICK PLANET!)
Jupiter grows brighter throughout the month and as it rises earlier throughout October as well, will become all the more prominent. At month's beginning, the fifth sphere rises just before 10:00 p.m. At month's end, it rises around 8:00 p.m. Jupiter started a retrograde loop on October 4th which continues through the remainder of 2012. One can observe Jupiter's changing position relative to Aldebaran, the brightest star in Taurus the Bull. (The planet and star will be 8 degrees apart at month's beginning; 7 degrees apart at month's end; and 5 degrees apart by the end of November.) VERDICT: Unless you go to sleep early, you'll want to see this brilliant planet in the mid evening eastern sky.
After adorning our spring and summer skies, Saturn retreats backstage for a blissful lie-down after the first week. Saturn is in conjunction with the Sun on October 25th and won't be visible again until November. VERDICT: Well, from the Book of Pointless Adages, if it isn't visible, you can't see it. You MIGHT glimpse Saturn low in the western dusk sky, but will be exceedingly difficult to observe. Saturn admirers should wait until mid November when the Lord of the Rings ascends in the pre-dawn eastern sky.