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Jupiter is always an awesome target.
You'll see the same moons Galileo saw in 1610. They're those "stars" in a line on either side of Jupiter. How many do you see?
Except when it's close to the sun (technically, when the Earth swings around the far side of the sun relative to the slow-moving Jupiter) it's big enough to make out the four Galilean Moons and likely some cloud bands with even a modest consumer telescope. Yes! Even that "junk" telescope you got for Christmas, at a garage sale or from craigslist will show these features on almost any night.
With a decent, but still modest, scope you might be able to pick out the Great Red Spot (although it's a sublte salmon - it doesn't "pop out" the way it once did) and more than just the two most prominent equatorial cloud bands.
Jupiter is dynamic. It fully rotates over the course of 10 hours. That means if you look at Jupiter and then look again an hour later, you'll see change. Across any given five our window on any evening, the Great Red Spot will be staring at you.
The moons will show movement as well.
Mark Collins of San Diego - an "amateur" astrophotographer (something of an misnomer - "amateurs" can image targets and durations that "professionals" simply cannot or do not) - shot Jupiter over a course of two hours. Watch the Great Red Spot rotate into view and the volcanic moon Io move across and off the planet's disc:
At any given glance with binoculars or a small telescope you may see all four Galiliean moons scattered on either side of Jupiter, but sometimes one or more is behind or in front of the bright disc of the planet.
Those big Gallilean moons regularly and predictably transit in front of Jupiter and drag their shadows across Jupiter's disc. Mark's amazing shot above was taken near opposition, which throws the shadow right behind the moons. Normally the shadows precede or trail the moon (because of Earth's varying off-axis angle between the Sun and Jupiter); picking out a whitish moon in front of whitish Jupiter is a little trickier.
SkySafari and other apps will show the moons' positions at any time, transit times are published. Transits are pretty amazing - ingress and egress happen in real time, about as fast as a sunset. You can see movement (that's actually rare in observing outside of sunrise, sunset, moonrise, moonset - it's hard to see celestial movement).
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On any given night, you can see Saturn's rings with a small telescope or even binoculars.
Granted, some nights are better than others, but even on a "bad" night seeing Saturn has an amazingly high Wow-ratio:
(more than anything I've tried to share in my life. People overwhelmingly love Saturn at first glance. Kate Bush is equally amazing, but only 0.005% are amazed by her at first listen)
Saturn's Rings are Disappearing!!!!
I saw this click-bait headline. Yes. Saturn's rings are diminishing in appearance until March 2025 when they won't be visible at all!!!
But they'll be back! It's all a part of the orbital optical illusion as Saturn swings along it long 29-year orbit.
The rings are currently, sadly, in the part of the cycle where they appear flatter/thinner due to its tilt in its orbit. We'll see less and less of the rings until March 2025 when they'll be invisible. Then they'll start the cycle over again, broading up to a maximum of 27 degrees a quarter of it's year later (2032).
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https://commons.wikimedia.org/wiki/File:Saturnoppositions-animated.gif |
The animation above is the variation we'd see in the Saturn's tilt we'd see if we watched it over the course of its year (the Saturn year is 29.5 earth years. From flat to full takes a quarter of that, a little over seven years. Note that it's an illusion from persective: the tilt does not change orientation, it appears to based on it's position relative to the sun. Exactly like our seasons.
Saturn near Opposition
Saturn's Oppostion - when the earth is closest to it and it appears biggest and brightest - occurred this year (2024) on Sep 8.
By definition, Saturn will be Opposite the Sun, meaning it rises when the sun goes down.
Celestial Targets seldom look good when they're close to the horizon, so give it 90 minutes or two hours to get a good look, Targets typically look best when they are obscured by the least amount of atmosphere - directly over head (rare) or passing through the meridian (the line running south to north through the local "up". Think am and pm (ante-meridian and post-meridian).
In addition to the typical outer planets looking bigger and brighter at opposiition, Saturn has a fleeting mythical effect known as the Seelinger Effect when, for a few hours around opposition, the rings' icy particles reflect the sunlight extra brightly. It's like the Green Flash, you can see it if you're lucky - though with the Green Flash you get over 300x more chances to see it.
Saturn after Oppostion
After Opposition, Earth moves away from Saturn, making it looking continually smaller until it appears to "disappear" behind the Sun. The good news is that Saturn is a gas giant, so it's BIG. It always looks good. And, after Opposition, it continues is westward march toward the Sun. This means it is observable immediately after sunset (at opposition you have to wait several hours before it clears the long murky air near the horizon).
source: https://commons.wikimedia.org/wiki/File:Saturnoppositions.jpg
here's a link to a chart of its tilt as seen from earth: https://images.app.goo.gl/6dE3mvQBe4S7CpPp6
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Let's assume you have a weekend with a dark sky.
Let's assume you have an Observing List and there are a LOT of great targets available.
Let's assume it's an outreach event and you have different types of telescopes.
How do you ensure the best observing experience for the event?
One way is to tailor the Observign Lists for each scope according to its strengths.
Giant Tracking Newtonian
| Strengths | Weeknesses | Best Targets | |
| Giant Tracking Newtonian | Everything | ||
| Tracking 10" Dobsonian | |||
| Manual 10" Dobsonian | |||
| GoTo 9.25" SCT | |||
| GoTo 8" SCT w Wide Field refractor | |||
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Manual Alt-Az Refractor (APO) |
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| Manual Alt-Az Refractor (Achro) | |||