November 2011

November best time to view Jupiter


Heading out any clear night this month the observer’s eye will be caught by a bright yellow “star” in the eastern sky. This is not a star. This is the planet Jupiter. It is not only its brilliance that makes it so obvious but also the lack of bright background stars.

Residing in the constellation of Aries, whose brightest star is magnitude 2.0, Jupiter shines at a magnitude of -2.9. This means that the Giant Planet blazes about 100 times brighter than the stars in Aries.

This month will be the best in which to observe Jupiter. It will be well placed in the eastern sky after sunset, especially when Daylight Savings Time ends. Jupiter was at opposition on October 29 at which time it was closest to us.

Views of this planet in a telescope always amaze observers the first time they see it. The Jupiter system is a dynamic one where there is always a change each night you observe it. The most obvious is the four Galilean satellites (Io, Europa, Ganymede and Callisto). They are visible in the smallest telescope and even steadily supported 10×50 binoculars. Observing them nightly will reveal them in different positions around Jupiter. Sometimes they disappear behind and pass in front of the planet as well. The most obvious feature on Jupiter is its two relatively dark equatorial bands as seen in a telescope. When we look at Jupiter we are actually looking at its cloud tops. This planet is classed as a gas giant along with Saturn, Uranus and Neptune as they have no actual solid surface. More detailed examination of Jupiter will show alternating light and dark bands. On nights when the Earth’s atmosphere is steady closer examination will reveal features within the cloud bands such as ovals, festoons and the Great Red Spot.

Mars makes its appearance around 2:00 a.m. (EDT) at the beginning of November as it rises in the east. At this time it is in the constellation of Leo. The Red Planet is starting to brighten as it approaches opposition (closest approach) early in March next year. Mars is too far from us at this point thus appears too small to make out any surface details in smaller telescopes. This situation will improve dramatically as the Earth catches up with the Red Planet over the next few months.

The Leonid meteor shower is a well known event this time of year. These meteors are the result of a debris trail left behind comet 55P/Tempel-Tuttle along its orbital path around the sun. The Earth passes through this trail of fragments once a year. As it does so this material enters the atmosphere at a high speed and is incinerated in a flash of light. It is this flash of light against the night sky that we see as a meteor. The number of meteors we see depends on the amount of material the Earth passes through at that time. This year we are not expected to see a lot of meteors (maybe 10 per hour). This is only a prediction, we have been wrong in the past. The Leonids will peak the night of November 17. The moon will be waning gibbous that night which will wash out the fainter meteors.

November opens with a waxing crescent moon just entering the constellation of Capricorn. By November 9 the near full moon has positioned itself to the left of Jupiter. The next night the lunar phase becomes full and is known as the Beaver Moon. The full moon last month was the Hunter’s Moon. Before sunrise on the morning of November 19 the waning crescent moon can be found below the planet Mars (reddish-orange) and the star Regulus (blue-white) in the constellation of Leo.

As a reminder, on the night of Saturday, November 5 remember to “fall back” an hour. At this time we will be leaving Eastern Daylight Time (EDT) to resume Eastern Standard Time (EST) for the rest of the autumn and throughout the winter seasons.

The Thunder Bay Centre of the Royal Astronomical Society of Canada extends an invitation to all interested observers to attend the public observing session to be held at Hillcrest Park on Friday, November 4 beginning around 8:00 p.m. EDT until 11:00 p.m. EDT. Centre members will have telescopes and binoculars available to observe the planet Jupiter as well as the Moon and other celestial objects. If the skies are cloudy the event will be held the next evening (November 5). Bring warm clothes and your astronomy questions for our group.

Clear Skies

Ted Bronson