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1 vote
1 answer
124 views

Identify the bright object to the left of the moon

I'm seeing the sky at 23:00 on September 29, 2023, from the east of Algeria's point of view. To the left of the moon, there is something very bright. I need to confirm if it's Jupiter? (My camera ...
7 votes
2 answers
744 views

Computing orbit positions of Jovian Satellites / Moons using JPL data

I've been trying to build a model of the solar system in a game. Thus far I've succeeded in placing each of the planets in position using Keplerian elements and formulae from https://ssd.jpl.nasa.gov/...
18 votes
3 answers
4k views

What is this 877-year cycle in the orbits of Jupiter & Saturn, and this multimillion-year cycle in the lunar orbit?

The book The Theory That Would Not Die (by Sharon Bertsch McGrayne, 2011) states the following on page 28: He [Pierre-Simon Laplace] used other methods between 1785 and 1788 to determine that Jupiter ...
1 vote
1 answer
275 views

Can I use 75mm Plano convex lens to build telescope [closed]

I want to see Jupiter with moon. So am planning to build telescope. Can I use 75mm Plano convex lens with 1000mm focal length?
10 votes
2 answers
8k views

What would happen if Jupiter and Earth were at the same distance as the Moon is from Earth?

If Spock came with a super machine capable of moving planets, and placed Earth so close to Jupiter as the Earth's moon, the gravity of Jupiter would make us fall into it?
3 votes
1 answer
636 views

How big and how far away would the moon be if earth was the size of Jupiter?

If the earth were the size of Jupiter, what would its 'moon' be in both relative size and distance? I did some quick figuring and think I roughly figured out that if placed at the position of the sun, ...
5 votes
2 answers
268 views

Solar wind, Earth wind and planetary winds?

In February 2021, a new form of "electrified gas breeze" was announced, see blog by Tony Phillips entitled A New Form of Space Weather: Earth Wind which might a possible explanation for ...
1 vote
0 answers
130 views

Meteor size and frequency distribution for Earth vs. moon or other planets?

I struggle to find an answer to the at-first-sight simple question if or how the size distribution and frequency distribution of incoming rocks hitting the ground or the atmosphere vary from Earth, to ...
2 votes
1 answer
211 views

How to understand this multi-day exposure photograph of Jupiter and the Moon

This answer includes a stunning photo of the Moon and Jupiter "Trails of the Shifting Moon" by photographer Jin Lu. The caption reads: From the photographer: "I spent 4 days capturing the trail of ...
1 vote
1 answer
218 views

What should I improve my telescope kit to see more details of Moon?

What should I improve my telescope kit to see more details of Moon? I have the gskyer telescope of 60mm aperture and 350mm focal length. my eyepieces are 10mm,25mm. and I have x3 Barlow. my best ...
3 votes
1 answer
357 views

Eclipses of Jupiter's Moon during Retrograde motion

When Jupiter is undergoing retrograde motion as seen from the Earth, would you expect the eclipses of Jupiter’s moons to occur several minutes early, several minutes late, or neither? Can someone ...