Starship Asterisk*

APOD has been so reliable, day after day for years, it didn't occur to me that there was a problem at GSFC. After all these years, it actually became unthinkable that APOD was down. :ssmile: Living in Australia, I'd heard about the storms and power outages in the US, but didn't make the connection. ...

There seems to be a faint spot below Venus and a little bit to the right. Any ideas what this is? I don't think the distortion of the sun is extreme enough for Venus to appear twice because it is not directly underneath. The only thing I can think of is dust on the mirror inside the camera (assuming...

APOD Robot wrote: NGC 7822 in Cepheus

In the top-middle of the picture is a dark cloud. Is that at the same distance as the nebula (i.e. is it a part of the nebula, lit on the side facing away from us, or is it just an intervening dark cloud)?

... ∞ is not an integer, so your statement "for all numbers x, where x is a member of the set of integers, there is no x such that the successor of x is ∞" is true by default, because ∞ is not a part of the set. That does not mean there exists a greatest integer. I believe I should have w...

Your Test for Existence is a logical fallacy, denying the antecedent . If it can be found, then it exists. It hasn't been found, therefore it doesn't exist. Symbolically: If P , then Q . Not P , therefore not Q . This simply doesn't hold. Post 1 of 2 (it's very late where I am). I'd like to say tha...

Hmmm... lots to think about there thanks. I'm going to go over my predicate logic before posting a reply to the second part, but there IS a reply. Meanwhile the first part is very interesting too: Cantor had to define integers as infinite because of the axiom of infinity... I do wonder if Chris L Pe...

Can anyone imagine a line which has no end? I can't imagine anything which has no end. In other words I don't believe absolute infinity. I am not sure whether the concept of infinity is relative. However, i feel so. Can anyone kindly put their valuable comments on the following two: 1. The universe...

If, as you say, 10 80 exists, then surely 10 23 exists. By definition, your set of integers are closed under the operation of multiplication. 10 80 × 10 23 = 10 103 . 10 103 must exist. BTW, by definition, your set of integers is countably infinite . Even with "the business about quantized len...

If length is quantized then it follows there's an integer number of Planck lengths from one side of the observable universe to the other. Always have been and always will be. Likewise if time is quantized, which it is, then there have been an integer number of Planck times since the big bang. If th...

... Furthermore, even the elusive never-seen first stars in the universe, so-called Population III stars, are predicted to have a large mass and a small but set amount of heavy elements. ... Ummm... from following the links it seems that our sun would be a generation III star and these elusive neve...

... Furthermore, even the elusive never-seen first stars in the universe, so-called Population III stars, are predicted to have a large mass and a small but set amount of heavy elements. ... Ummm... from following the links it seems that our sun would be a generation III star and these elusive neve...

Can anyone imagine a line which has no end? I can't imagine anything which has no end. In other words I don't believe absolute infinity. I am not sure whether the concept of infinity is relative. However, i feel so. Can anyone kindly put their valuable comments on the following two: 1. The universe...

I've just watched Lecture 1 (and read some of the Wikipedia pages referenced in the lecture). I don't know if this makes sense to you but it would be nice to have a mini-test to take after watching lecture one, just to make sure I'm following up to the 'correct extent'. Then, based on the results of...