Recent content by DrJoePesce

Hi StarmanG10, At this point, with dark energy causing the acceleration of the universal expansion, I would say the vast, cold, infinite expanding universe is the most likely. In the far distant future, the universal expansion will cause atomic nuclei to split apart and that's it for the...

Hi Think twice! Great question. Let's give a bit of background (without going too deep): so-called "emission lines" in a spectrum come about because an electron in an atom drops from a high orbit to a lower orbit. Electrons can be thought of in orbit around the proton(s) and neutron(s) in an...

Hi Marc, I see that Cat replied to you. Does that response answer your questions? The thing that is neat here is that the universe is making an array of planets, in formations we didn't think possible. This just means our understanding is not complete. But now that we see things are...

Hmmm. I'm sorry for my absence. But.... I've checked the site periodically and it didn't show anything after my reponses in March. Don't know what happened. Let me review the more recent entries and get back to you ASAP!

Dear Cat, I love the questions (even if sometimes I'm unable to fully answer!). And I think you might not be satisfied with this: Our universe is just that way - space and time are combined. We have Einstein to thank for this. I can't provide a response to WHY, but that is just my...

Welcome billiejean!

Hi Cat, good to hear from you! The main difference between space and spacetime is….time! “Space” is where everything is located. You can define positions with coordinates. There are three dimensions, x, y, and z (or left/right, forward/back, up/down). “Spacetime” consists of the three...

Hi Cat! Well, aether in the "classical" sense, fills/permeates space. What I'm talking about in the extract above IS space: The fabric of space itself is affected by the gravitational wave as it travels (at the speed of light) through space. Dr Joe

Hey Josh, Thanks for the great question. The waves are affecting space time, which is the material being stretched and compressed. But everything is embedded in space time, since space time is being distorted, the subatomic particles that make up atoms and molecules are being distorted too...

Thanks for this. Very interesting. Certainly this is possible, theoretically, but as noted in the video it would be very difficult to do in practice. Gravitational lensing, of the sort this video mentions (but with stars), has been used in astronomical satellite missions. Dr Joe

Hi Joshua - thanks for the post. It's been quiet around here and I was just going to see how everyone is doing. I guess you are all poring over the JWST images! Inteferometery! It's a subject near to my heart, as the official responsible for most of the US's radio astronomy facilities...

Hi Orion! ' I've just posted some pieces from an interview at NSF showing my reactions (also here: https://www.youtube.com/watch?v=ulWAn623l9Q). The summary is: The images are fantastic, and the JWST is a phenomenal instrument, as we expected it to be. I am really excited to see what comes...

Here are some links for you! (ignore the grammar errors - at least you know I'm not AI!): A longer piece: https://youtu.be/ulWAn623l9Q And some shorts from that: https://youtu.be/ulWAn623l9Q https://www.youtube.com/shorts/JNmfYXixWHk

Hello Astronomy enthusiasts! Join me tomorrow, 12 July 2022, in the afternoon at the NSF YouTube page, where I discuss astronomy and the new JWST images! https://www.youtube.com/channel/UCRuCgmzhczsm89jzPtN2Wuw (I'll post a permanent link to the interview after the fact - so don't worry if you...

Hi Poodlepupboy! That sounds lovely! I have a nice place to look up and think, too. The full answer to your excellent question is a complicated one and requires a lot of speculation that may or may not be sound. So let's skip that. I think the answer is no, it's not infinite. One (maybe...