This Week’s Sky at a Glance, 2023 Nov. 11 – Nov.18
This Week’s Sky at a Glance, 2023 Nov. 11 – Nov.18
Jupiter is like a miniature version of the solar system, having four large satellites or moons that we can see with binoculars – Io, Europa, Ganymede and Callisto in order of distance – and four smaller moons orbiting closer but beyond the reach of most amateur telescopes. Just as other large bodies are being discovered in the Kuiper Belt beyond Neptune, the tally of moons beyond Jupiter’s large ones keeps increasing (87 at the moment for a total of 95).
When a moon passes behind Jupiter and comes into view on the other side hours later, these events are called an occultation disappearance and reappearance. Often they also pass into and out of Jupiter’s shadow, called an eclipse disappearance and reappearance. They can be seen with mounted binoculars but a telescope will show them better. A telescope, preferably a larger one and with high magnification, is required to see the moons transit or cross in front of Jupiter, and then with difficulty unless they are just entering or exiting (called ingress and egress). Easier to see is the shadow of a moon transiting as a small black circle, preceding the moon before Jupiter reaches opposition and trailing after opposition. The two outer moons, Ganymede and especially Callisto, sometimes pass above and below Jupiter when the planet appears tilted to our point of view.
The Red Spot is a large storm in Jupiter’s atmosphere, perhaps looking reddish or salmon-coloured in a larger telescope at high power. Jupiter has two brownish gas belts above and below the equator, and the Red Spot is on the outer edge of the southern belt (which could appear above the equator, depending on the type of telescope). The Red Spot transits, or appears in the middle of Jupiter, every ten hours as the planet rotates. A monthly calendar is posted on the websites or Facebook pages of the local astronomy clubs, showing the types and times of Jupiter’s visible moon action and the Red Spot transits up to 1 am.
This Week in the Solar System
Saturday’s sunrise in Moncton is at 7:13 and sunset will occur at 4:51, giving 9 hours, 38 minutes of daylight (7:16 and 4:59 in Saint John). Next Saturday the Sun will rise at 7:23 and set at 4:44, giving 9 hours, 21 minutes of daylight (7:26 and 4:51 in Saint John).
The Moon is new on Monday, so this weekend and early in the week will be opportune times for observing those faint objects such as galaxies and comets. Jupiter and Saturn are optimal telescope targets all evening throughout the week. On Sunday you can observe the moon Europa disappear behind Jupiter at 5:41, reappear at 8:30, and later see the moon Io disappear at 11:56 while the Red Spot is visible. Around 6 am this weekend Venus and the bright stars Arcturus, Sirius and Rigel will be at nearly the same altitude stretching from east to southwest, with Jupiter sinking in the west. Uranus reaches opposition on Monday, and next weekend Mars will be in conjunction far behind the Sun. The north Taurid meteor shower peaks this weekend while the Leonids peak next weekend, providing a few extra shooting stars for our viewing pleasure.
The Fredericton Astronomy Club meets on Tuesday at 7 pm in the UNB Forestry-Earth Sciences building. There will be public observing at the Irving Nature Park in Saint John next Friday from 6:30 – 9 pm.