Question for the clever Aspies

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How come other planets don't get in the way of our view of the sun? When the moon passes the sun we get an eclipse, but other planets never do this.
And how come we never see the other planets like we can the moon? I understand that the light of the sun reflects on to the moon making it visible to us, but how come the same doesn't happen to other planets? (Unless you have a telescope).

Because the other planets are much further away from us than the moon.

The moon is 400,000 kilometers from Earth but the Venus is 40 million kilometers from Earth (when it's on the same side of the sun). That's 100 times the distance but Venus is only 3.4 times bigger than the moon (by diameter).

Mars is 77 million kilometers from Earth (when it's on the same side of the sun) so same deal.

Venus does pass in front of the Sun but at such a great distance and with the glaring light of the sun it's too small to be seen. It's easy to see an lunar eclipse because the moon blocks out nearly all the light of the sun. Venus is so far away that against the sun it appears only as a tiny black dot.

The transit of Venus across the sun can't be seen with the naked eye but it appears in photos that have been zoomed in a lot like the photo below. As you can see, Venus could never block our view of the sun. Only Venus and Mercury pass between Earth and the sun.

The planets in our solar system can be seen with the naked eye except for Uranus and Neptune (because those planets are too far away). Without a telescope you can see Mercury, Venus, Mars, Jupiter and Saturn.

You can't see them clearly like the moon because they're so far away they only appear as tiny white dots. Actually they could easily be mistaken for stars.

Venus and Mercury even have phases like the moon but these phases can only been seen through a telescope. Only planets that are closer to the sun than Earth have phases when viewed from Earth.

Perspective.

Thank you for the fascinating replies. I don't often think about the universe but it does fascinate me. I have so many questions about it what I can't find on Google.

Feel free to ask us

Ah, but they do! Astronomers call it a transit rather than an eclipse, but it's exactly the same thing. Here's Venus doing just that:



And here's Mercury doing the same:



Mercury and Venus are the only two planets that get between us and the sun, so they are the only ones that can "eclipse" the sun in this way.

I've spent a decent portion of my life thinking about the universe. I the universe and all its quirkiness or maybe it's quarkiness.

1. The outer planets cannot get in our way
2. The moon is so close it subtends a spherical angle equal to that of the Sun itself. That is why the moon just covers the sun during a total eclips.
3. The inner planets Venus and Mercury are so small that when they cross the sun they look like dots.

If you think all the stuff about the universe is cool then check out the quantum world, there's loads of stuff on youtube about it. Check out the Morgan Freeman program called Through the wormhole, this will answer many questions and make you ask many more.

Quantum physics is a lot of fun but if you want something simpler you could look into the Theory of Relativity.