# Thread: Time of maximum visibility of Jupiter.

1. ## Time of maximum visibility of Jupiter.

Hi:

I imagine threre must be, in the last 100 years, one or more instants in which Jupiter's visibility was at a maximum. I call this instant, t_0. Further on, there should have been, I guess, a time t_1 in which the visibility was exactly the same. And taking T = t_1 - t_0, I could speak of a period T, in regard to the visibility of Jupiter as observed from the Earth, not taking into accont, of course, local phenomena like clouds and the like. Any hint will be welcome.

2. Hi STF,
Welcome to the Forum!
Astrologers, predecessors of astronomers, knew that full cycle of Jupiter in regard to an Earth's observer is 60 Lunar years. So, we have 12 signs of Chinese horoscope spread over 5 elements. In some more complex detail here www.ancientcartography.net/JupiterCalendar3.pdf

3. Define "maximum visibility". Jupiter is a superior planet, so about every 13 months we are in conjunction with it and it is at its largest and brightest. Since the orbit of both Jupiter and the Earth are eccentric, there are times when Jupiter will be closest to the sun (perihelion) and the Earth is farthest to the sun (aphelion), which means the two are closest together. This doesn't necessarily coincide with conjunction though, so having Earth at aphelion, Jupiter at perihelion and both in conjunction would be very rare.

The most recent pass we had was very close to Jupiter (closest since 1963), and we'll be even closer in 2022. Because there's so many factors that affect how close we approach to Jupiter, unless you're just looking at conjunction then there is no simple period of maximum brightness.

4. ## The Following 2 Users Say Thank You to DaveW For This Useful Post:

Joe Lalumia (11-22-2010),rwsandy (11-22-2010)

5. DaveW is correct. Jupiter is BIG and BRIGHT-- most of the time. The small differences in a true "close approach" are overshadowed by seeing conditions, which are much more important for detailed viewing.

Even HEIGHT above the horizon is more important.

6. ## The Following 3 Users Say Thank You to Joe Lalumia For This Useful Post:

mplanet62 (11-23-2010),porkchopsisgood (11-24-2010),rwsandy (11-22-2010)

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