the moon the sun the earth and eclipses The Moon and Eclipses

[kausgx]

The Moon, the Earth, the Sun, and Eclipses.

Also, is the Moon Artificial 

 

I keep hearing about the solar eclipse and how rare it is to have one in our solar system.

No one talks about the Earths shadow and its relationship to the size of the Moon and along with the relationship to the sun and the distances between them. Also we can tell if the moon is moving towards or away from the Earth by the shadows size in relationship to the Moon.   

[Stu]

20 hours ago, kausgx said:

The Moon, the Earth, the Sun, and Eclipses.

Also, is the Moon Artificial 

 

I keep hearing about the solar eclipse and how rare it is to have one in our solar system.

No one talks about the Earths shadow and its relationship to the size of the Moon and along with the relationship to the sun and the distances between them. Also we can tell if the moon is moving towards or away from the Earth by the shadows size in relationship to the Moon.   

Disregarding the question about the Moon being artificial…… solar eclipses are not that rare, they happen regularly. What is rare is for them to happen at any one particular place ie they happen regularly but that can be spread across the globe so you normally have to travel to see them.

The Moon’s distance from us changes through its normal orbit, when it is further away during an eclipse it does not totally cover the Sun so you get an annular eclipse.

[Celerondon]

The moon is a natural satellite of planet Earth.  Natural planetary satellites (moons) are not uncommon in our solar system. In fact, most planets have natural satellites and many planets have more than one moon orbiting around them.  Even a small telescope can show the moons of Saturn and Jupiter as they travel through space with their planets.  
 

Jupiter’s moons are especially entertaining because the four largest ones are easily visible.  When Galileo first turned his DIY telescope towards the night sky he was more fascinated by Jupiter and its four largest satellites than by anything else that he viewed.  A telescope with a three or four inch aperture can show much more than the motions of the moons as they orbit Jupiter.  Even a small telescope can show eclipses, transits, and occultations as they occur between Jupiter and its moons. 
 

Don

[ccaissie]

My first POST!!!

I recently looked through a replica of Galileo's telescope at the Maine State Star Party. Although the field of view was like looking through a straw,  I understood that Galileo was able to witness the movement of Jupiter's moons and begin to open his mind to the reality of the ideas that were percolating at that time.  About 30mm objective masked to 15, and about 20x, it was enough.

[ccaissie]

So, to answer the eclipse question...when you see a Jovian moon shadow transiting the planet, anyone within that shadow is witnessing a Total Solar Eclipse.  this happens on Jupiter, Saturn, Uranus and Neptune....and of course Earth.  Phobos and Deimos are too small on Mars, and Mercury & Venus have no moon.

[RT65CB-SWL]

On 23/08/2023 at 19:13, kausgx said:

The Moon, the Earth, the Sun, and Eclipses.

Also, is the Moon Artificial 

 

I keep hearing about the solar eclipse and how rare it is to have one in our solar system.

No one talks about the Earths shadow and its relationship to the size of the Moon and along with the relationship to the sun and the distances between them. Also we can tell if the moon is moving towards or away from the Earth by the shadows size in relationship to the Moon.   

Hi @kausgx and welcome to SGL. 

1. ‘Artificial’ can you explain? - ‘Artificial’ is defined as to include man-made satellites, etc.
2. The Moon is moving away from the Earth at something like 1.5inches/4cms per annum. During a few of the Apollo missions [11, 14 & 15] the astronauts left reflective instruments known as Lunar Laser Ranger experiment on the surface in different areas. Every now and again the McDonald observatory in Texas or other observatories fires a laser at them. Depending on the time it takes reach and return, the astronomers/scientists at the NASA/JPL can more or less calculate the Earth/Moon distance. The Russian’s also left a French built one, via an unmanned lunar rover/mission.
3. At the time of writing, the Earth/Moon distance is approximately...

 

Hi also @ccaissie and welcome to SGL. 

On 01/09/2023 at 04:35, ccaissie said:

So, to answer the eclipse question...when you see a Jovian moon shadow transiting the planet, anyone within that shadow is witnessing a Total Solar Eclipse.  this happens on Jupiter, Saturn, Uranus and Neptune....and of course Earth.  Phobos and Deimos are too small on Mars, and Mercury & Venus have no moon.

1. As far as I know, a solar eclipse is when the disc of the Sun or star is obscured by another ‘body’ and you can see the corona, than it is a total solar eclipse. At some time in the future, the Earth/Moon distance will be so far apart, that we will be able to view an annular eclipses, [see below], not a total solar eclipse.
2. If you can see a ‘ring of fire’ around it, than that is an annular eclipse.
3. If it is totally obscured, than that is an occultation.

As the outer planets are so far away from the Sun and the outer planets moons are smaller than our Moon [excluding Jupiter’s moon, Ganymede and Saturn’s moon, Titan] then I guess that they would be annular eclipses or occultations.

As far as I know, no known images have been yet been seen of a solar eclipse from another planet within our solar system.

 

Edited September 2, 2023 by RT65CB-SWL

[Stu]

29 minutes ago, RT65CB-SWL said:

As far as I know, no known images have been yet been seen of a solar eclipse from another planet within our solar system.

Google gave me this which is interesting 👍

https://scienceillustrated.com.au/blog/science/space/do-other-planets-have-solar-eclipses/#:~:text=Do the other Solar System,happen throughout the Solar System.

[RT65CB-SWL]

Forgot to mention that a partial eclipse is when the disc of celestial body does not fully cover the disc of a celestial body from a given location if you are not at the centre line of its path.

Edited September 1, 2023 by RT65CB-SWL

[Mandy D]

2 hours ago, RT65CB-SWL said:

As the outer planets are so far away from the Sun and the outer planets moons are smaller than our Moon [excluding Jupiter’s moon, Ganymede and Saturn’s moon, Titan] then I guess that they would be annular eclipses or occultations.

As far as I know, no known images have been yet been seen of a solar eclipse from another planet within our solar system.

 

Don't forget that at the great distances of the outer planets, the Sun will also appear smaller, so, yes, there will be total eclipses. All of the gas giants have moons large enough and close enough to totally eclipse the Sun. Pluto's moon, Charon, also eclipsees the Sun as seen from Pluto.  Interestingly, but not surprisingly, total eclipses of the Sun by a planet are visible from it's moons, Mars included.

Solar transits of both Phobos and Deimos have been captured by cameras on Mars rovers.

[Space Hopper]

26 minutes ago, Mandy D said:

Interestingly, but not surprisingly, total eclipses of the Sun by a planet are visible from it's moons, Mars included.

 

Well, sort of.

 

[RT65CB-SWL]

I understand what @Stu and @Mandy D are saying. I have seen images/photos of eclipses from other planets and moons of our solar system via probes that have landed on their surfaces.

When the average person in the street thinks eclipse, they think of our Moon covering the disc of the Sun as viewed from Earth and revealing the corona.

Therefore an eclipse can be defined as an object is in front of another and the one behind it is obscured. I should have made it clearer to understand in my first reply.

Edited September 1, 2023 by RT65CB-SWL

[Stu]

4 minutes ago, RT65CB-SWL said:

Therefore an eclipse is when when any object is in front of another and the one behind it is obscured. I should have made it clearer to understand in my first reply.

The only thing is would add to that is that an eclipse happens whenever an object passes infront of the other. A TOTAL eclipse is when the more distance object is completely obscured, a partial eclipse is when some of it can still be seen.

I think the issue of whether the corona of a star can be seen is likely unique to our situation as the Moon is effectively the same size as the solar disk (excepting annular eclipses), so the corona can be seen but it’s not part of the definition of an eclipse I would say.

[Mandy D]

9 minutes ago, Space Hopper said:

Well, sort of.

 

No, this is definitely not what I was referring to, as that is a solar transit. It is imagery of one of Mars' moons transiting the Sun. What I said was total eclipses of the Sun by the planet from it's moons.

[Space Hopper]

Sorry Mandy, my bad. Misread your post.

But lets hypothetically assume Phobos was 3 times the size (its only about 20 miles wide but orbits very close to Mars)

Would this 'transit' then become a total solar eclipse ?

It would be interesting to watch one from Phobos though ; it would probably last a while ?

[DirkSteele]

Sky and Telescope published an article about how rare eclipses of the sun are (spoiler, they are not with an average of 2.38 per year for the 2000 year period 1001 AD to 3000 AD - this covers partial, total, annular and hybrid). However, each one covers less than 1% of the Earth’s surface and there is normally more than 300 years between eclipses passing over the same point which makes them seem rare. What is unusual or perhaps rare, in terms of eclipses is the apparent diameter of the moon and sun being the same to permit total eclipses and observation of the corona.

 

https://skyandtelescope.org/2024-total-solar-eclipse/how-rare-is-a-solar-eclipse/

[Mandy D]

17 hours ago, Space Hopper said:

Sorry Mandy, my bad. Misread your post.

But lets hypothetically assume Phobos was 3 times the size (its only about 20 miles wide but orbits very close to Mars)

Would this 'transit' then become a total solar eclipse ?

It would be interesting to watch one from Phobos though ; it would probably last a while ?

Well, that is very easy to check. I cropped Phobos out of NASA's imagery and scaled my own image of the Sun to the same size as in the original NASA image, then I scaled Phobos to three times it's original size and overlaid everything onto a dark blue background, so you can see what would happen during the late partial stages of a solar eclipse as seen from Mars under your prescribed conditions.

Given that Phobos orbits quite close to Mars, it's apparent movement in the sky would be very rapid, so the eclipse would likely last seconds at most.

Edited September 2, 2023 by Mandy D

[Space Hopper]

Thats excellent, thank you. Fascinating stuff.

And yes, it would be a very quick eclipse : no time to see Baily's beads...! 😁

[Mandy D]

4 hours ago, Space Hopper said:

Thats excellent, thank you. Fascinating stuff.

And yes, it would be a very quick eclipse : no time to see Baily's beads...! 😁

Now, here is another interesting thought. Phobos chaotically tumbles from time to time in it's orbit and has an irregular shape, so the eclipses can all look very different. If we chose the orbital distance carefully, we could then have a wide range of different types of eclipse, with some not fully eclipsing the Sun when Phobos is centred on it and others where it obstructs a band across the centre-line of the Sun, etc, etc.

Edited September 2, 2023 by Mandy D
Dang typo!

[Gfamily]

On 01/09/2023 at 15:19, Mandy D said:

No, this is definitely not what I was referring to, as that is a solar transit. It is imagery of one of Mars' moons transiting the Sun. What I said was total eclipses of the Sun by the planet from it's moons.

Yes. I understood you to mean the equivalent of a lunar eclipse, where the moon goes into the shadow of the planet. 

[powerlord]

AI post ?

[The60mmKid]

We must also consider whether the earth is artificial.

Just sayin'...

[Pete Presland]

Hi welcome to SGL from Pete in Bedfordshire  🙂