| Observatory |
Some observing hilights
to look forward to...
The following tips on current and upcoming astronomical events
have been gathered from magazines and other sources by Dave Gamble
with the objective of giving OC RASC members a heads-up on
special personal astro-experiences to look forward to.
Thurs. Oct. 1 - Tonight celebrates the bounty of the fall season with the annual Harvest Moon, the full Moon closest to the autumnal equinox. In earlier times the Moon performed a useful and important function by adding light to late evening harvest operations, not just for one night, but several in a row. This is because in fall Luna is moving higher along the ecliptic which compensates somewhat for its eastwardly movement each night.
Thurs. Oct. 1 - Mercury has reached its greatest eastern elongation, however with the shallow slope of the ecliptic at this time of the year it does not reach very high into the western sky after sunset. Binoculars may help you spot the innermost planet in the twilight just off to the left of where the Sun ducked below the horizon.
Fri. Oct. 2 - This month is Mars’ time to shine as it approaches its current opposition next Tuesday. Tonight the just past full Moon will check things out, rising in the southeast close to the red planet. The pair will provide a beautiful sight as they traverse the sky throughout the night.
Sat. Oct. 3 - Venus has been celebrating most of the year as the ‘Morning Star'. In the pre-dawn sky this morning our brilliant neighbour will appear about a moon-width from the bright star Regulus in Leo which is just beginning its crawl across the night sky towards its performance as the main evening constellation next spring.
Sat. Oct. 3 – Tonight the ‘Demon Star’ Algol will give us a subtle wink. This is a gradual event lasting about two hours, centred at 9.48pm. Check the star in Perseus around 8pm and compare its brightness with surrounding stars, then revisit it at its dimmest around 10pm. You may share the experience of what was once a huge mystery to observers before Algol was discovered to be an eclipsing binary star.
Sun. Oct. 4 - This is also a good time to look for a different kind of variable star that can’t always be seen, as Alan W pointed out last week. Mira ‘the wonderful’ was first recognized as a long period variable star in 1596. It remains too faint to be seen with the naked eye for much of its 11 month cycle, however right now it’s approaching its maximum brightness, and in the process altering the appearance of its home constellation Cetus by adding a new fairly bright orange coloured star. You can check it out by looking to the lower left of similarly hued Mars, but a star chart will help. At home, perhaps 220 light years away, Mira is an unstable pulsating red giant star which is losing mass to its high temperature white dwarf companion.
Tues. Oct. 6 - This fall the night sky has been headlined by the growing brightness of Mars. Tonight our ruddy neighbour will be at its nearest approach to Earth during the current biennial visit, even though it will not reach opposition (directly opposite the Sun from the Earth) until the 13th due to its eccentric orbit. While Mars' closest conjunctions occur in August and September, the advantage of this fall's visit is that it takes place higher in the sky, assisting telescope observers who have less turbulent atmosphere to deal with.
Tues. Oct. 6 - While tonight belongs to Mars, which will take the stage early in the evening, you might become a little distracted about three hours later when brilliant waning Luna peaks over the horizon less that three finger widths from bright Aldebaran in Taurus.
Thurs. Oct. 8 - Another reminder that the Zodiacal Light can be seen at its fall best at this time of year. Created by the Sun illuminating dust particles in the equatorial plane of the solar system, the faint elongated triangle of light extends up into the pre-dawn eastern sky with a bit of a tilt to the right, if you are fortunate enough to be able to view it from a dark sky site.
Sat. Oct. 10 - This is Last Quarter Moon night with the reverse half lit sphere rising in the early morning hours in the company of Pollux with its Geminid twin Castor looking on from just above. As well as being a beautiful sight, Luna’s last quarter stage brings joy to serious star lovers by signalling the approach of the next dark moon period, giving access to fainter deep sky objects.
Sun. Oct. 11 - In the wee hours of this morning Luna will be in close proximity to Messier 44. While she may outshine the fireflies of the Beehive Cluster, the combination should be stunning in binoculars.
Mon. Oct. 13 - Though Mars is moving away from Earth due to its eccentric orbit, tonight marks the official opposition of our outer neighbour when it is opposite to the Sun in our sky. During the coming weeks Mars will continue to put on a show that will not be surpassed until 2035. Soak in its brightness and distinctive colour with the naked eye or binoculars. If you have access to a reasonable telescope and find a night with steady air, you might be able to spot its diminishing white southern polar cap as well as dark surface markings.
Tues. Oct. 14 - While the Earth moves in its inside orbit ahead of Mars, Venus is doing the same thing to us, speeding ahead after reaching greatest western elongation in August and preparing for its next loop around the back of the Sun. Still very much the ‘Morning Star’ however, before dawn this morning it will rise just ahead of a dramatic waning crescent Moon below the brighter stars of Leo.
Wed. Oct. 15 - A reminder that we are still in the fall Zodiacal Light season. If you have dark sky conditions and a clear view of the eastern horizon (or can travel to a location that does), you might be able to glimpse the ghostly pyramid of faint light which reaches up from the horizon into the constellations Cancer and Gemini before morning twilight sets in. The effect is subtle but dramatic when you realize it represents sunlight reflecting off dust particles in the equatorial plane of the solar system.
Fri. Oct. 16 - This is New Moon night. Luna is tucked away in the direction of the Sun leaving a dark night sky, if the weatherman cooperates, inviting serious fun observing and imaging faint fuzzies and other deep sky denizens through binoculars or a telescope.
Tues. Oct. 20 - The Orionid meteor shower will peak tonight offering a great opportunity to try to ‘catch some falling stars’. The crescent Moon will set before the expected peak at 11pm PDST, leaving even the fainter members of the shower undiminished through the night. The radiant, near Orion’s club to the upper left of Betelgeuse, will be well placed in the eastern sky. About 15 meteors per hour can be expected from a dark sky location.
Tues. Oct. 20 – To provide a side show during the Orionid shower vigil, there will be another minimum of Algol tonight, with the two hour fainter period centred at 11.40pm. A ‘before’ look at the eclipsing binary’s brightness compared with neighbouring stars earlier in the evening will make its diminished brightness evident around 11.30pm.
Thurs. Oct. 22 - Perhaps a bit tired of playing second fiddle to Mars this month, tonight the gas giants Jupiter and Saturn will put on a show with the First Quarter Moon, forming a beautiful isosceles triangle with Luna anchoring the southernmost corner.
Fri. Oct. 23 - Fall is the time to catch the ‘Demon Star’ Algol in one of its blinks. A third favourable opportunity will occur tonight when the binary system will begin an eclipse at 7.29pm, reaching its dimmest level at 8.23pm, and regaining its brightness by 9.23pm. Here the plan would be to catch the celestial event around 8.30pm, comparing Algol’s brightness with its neighbours in Perseus then, and revisiting the scene later around 9.30pm to catch its noticeably brighter appearance.
Tues. Oct. 27 - Luna, in waxing gibbous mode, will provide a guide to the outer ice giant planet tonight. Neptune will be less than the width of three fingers above it.
Thurs. Oct. 29 - No, we haven’t forgotten about you Mars. Tonight we are looking forward to seeing our reddish neighbour, still brilliantly bright, introducing a waxing gibbous Luna less than three finger widths away. The beautiful sight of Mars’ ruddy brightness teamed with the Moon will be back on November 25, but with our planetary neighbour beginning to fade in brightness.
Sat. Oct. 31 - Hey, after all, it’s Halloween night! Tonight will mark the second Full Moon of the month which makes it a ‘Blue Moon’. Traditionally the Full Moon following the Harvest Moon was known as the Hunter’s Moon, so that is an additional distinction.