The Klein bottle is a monster:
A 4D object. My geometry skills struggle to understand it, I probably revert to my weaker Algebra skills.
Easy enough to do multi-dimensional maths with these babies. It's just algebra. You can calculate the answer.
What was clever about Klein, was he just saw it instantly. He was into projective geometry,
I am on it. Something to do with 4 variables in an arithmetical or geometric ratio.
A 4D object. My geometry skills struggle to understand it, I probably revert to my weaker Algebra skills.
Easy enough to do multi-dimensional maths with these babies. It's just algebra. You can calculate the answer.
What was clever about Klein, was he just saw it instantly. He was into projective geometry,
I am on it. Something to do with 4 variables in an arithmetical or geometric ratio.
Interesting events as I stumbled home tonight.
A girl was taking a snap of the Sky tonight on her Phone.
What she was snapping was an interesting conjunction between the New Moon, Jupiter and Saturn. Nice little triangle.
She asked me if the pink one was Mars. No, No, No. Mars is elsewhere, off to the left. Still bright.
"Thankyou so much."
Glad people still notice stuff.
A girl was taking a snap of the Sky tonight on her Phone.
What she was snapping was an interesting conjunction between the New Moon, Jupiter and Saturn. Nice little triangle.
She asked me if the pink one was Mars. No, No, No. Mars is elsewhere, off to the left. Still bright.
"Thankyou so much."
Glad people still notice stuff.
It's just been announced today that the famous Arecibo Observatory is to be decommissioned after its massive radio dish sustained damage which is too dangerous to repair.
Read the reasons why here: Arecibo radio telescope, an icon of astronomy, is lost | Space
And read the history of the Observatory here: Arecibo Observatory - Wikipedia
Read the reasons why here: Arecibo radio telescope, an icon of astronomy, is lost | Space
And read the history of the Observatory here: Arecibo Observatory - Wikipedia
Attachments
It's the same idea. One sided. but 4D in this case.
I am sure Arecibo is fixable. Just a question of money and will. But possibly obsolete now. A large array of small dishes can get to the same place.
Looks like a stitch in time would have saved 9 though. Poor maintenance.
Last edited:
The Chinese now have the biggest single RT in the world. But, as you mention there are new techniques using multiple dishes to simulate very large RT’s eg MeerKAT in South Africa and there are a few others currently under construction. They’ve already done some serious imaging with this one eg centre of the Milky Way identifying numerous stars orbiting The BH there.
MeerKAT - Wikipedia
Might be the end of SETI which IIRC used Arecibo primarily.
MeerKAT - Wikipedia
Might be the end of SETI which IIRC used Arecibo primarily.
Last edited:
The Murchison Widefield Array (MWA) telescope MWA - Telescope in Western Australia has searched the sky around the Vela constellation for signs of alien signals. This patch of sky contains at least 10 million stars, but is like a drop in the ocean compared to the total number of stars in our galaxy.
The search was also limited to radio signals that are similar to those of FM radio on Earth and it only lasted 17 hours. So, perhaps unsurprisingly, the search came up blank.
The attached image, captured by the MWA in 2019, shows the centre of the Milky Way Galaxy as it would look if humans could see radio waves
The search was also limited to radio signals that are similar to those of FM radio on Earth and it only lasted 17 hours. So, perhaps unsurprisingly, the search came up blank.
The attached image, captured by the MWA in 2019, shows the centre of the Milky Way Galaxy as it would look if humans could see radio waves
Attachments
Look at this image of tne centre of the Milky Way - incredible
MeerKAT radio telescope images Milky Way’s blazing heart – Astronomy Now
MeerKAT radio telescope images Milky Way’s blazing heart – Astronomy Now
Strange magnetic filaments around the central Black Hole in our galaxy indeed:
MeerKAT radio telescope images Milky Way’s blazing heart – Astronomy Now
I was curious about the "catwalk" to the central platform of Arecibo radio telescope:
Iconic Puerto Rico telescope to be dismantled amid collapse fears - BBC News
It's even scarier than I thought. Wouldn't catch me up there. I get vertigo!
MeerKAT radio telescope images Milky Way’s blazing heart – Astronomy Now
I was curious about the "catwalk" to the central platform of Arecibo radio telescope:
Iconic Puerto Rico telescope to be dismantled amid collapse fears - BBC News
It's even scarier than I thought. Wouldn't catch me up there. I get vertigo!
I get nervous on ship's gangways, and they have solid sides...
Found something that might relate to magnetic filaments:
The weird space that lies outside our Solar System - BBC Future
Those two 40-y-o space probes Voyager I and II are still sending back data about a thing called the Heliosphere about 10 times further away than Neptune. We can pick up the signal because our radio dishes have got much better than when they launched.
I didn't fully understand it, but it seems the solar wind actually protects us from cosmic rays coming in from the galaxy. Lots of particles and atoms swapping charge and magnetism. Space is not as empty as I thought.
Found something that might relate to magnetic filaments:
The weird space that lies outside our Solar System - BBC Future
Those two 40-y-o space probes Voyager I and II are still sending back data about a thing called the Heliosphere about 10 times further away than Neptune. We can pick up the signal because our radio dishes have got much better than when they launched.
I didn't fully understand it, but it seems the solar wind actually protects us from cosmic rays coming in from the galaxy. Lots of particles and atoms swapping charge and magnetism. Space is not as empty as I thought.
The BBC article borrows heavily from Wikipedia:
Heliosphere - Wikipedia
Seems there is a region about 6 times further out than Pluto where the incoming radiation starts to balance with the outgoing Solar Wind. Radiation levels then change dramatically with distance.
Considerably beyond that is the Oort cloud where adide comets IIRC.
Heliosphere - Wikipedia
Seems there is a region about 6 times further out than Pluto where the incoming radiation starts to balance with the outgoing Solar Wind. Radiation levels then change dramatically with distance.
Considerably beyond that is the Oort cloud where adide comets IIRC.
I've just tackled the BBC article - very interesting.
The idea that the Sun, with its planetary system in tow, leaves behind a wake as it ploughs its way through the interstellar medium is fascinating.
The two Voyager probes are now interstellar travellers, but are not headed towards any particular star. If they were headed to our nearest neighbour, Proxima Centauri, just 4 light-years away, they wouldn't reach it for another 80,000 years!
The idea that the Sun, with its planetary system in tow, leaves behind a wake as it ploughs its way through the interstellar medium is fascinating.
The two Voyager probes are now interstellar travellers, but are not headed towards any particular star. If they were headed to our nearest neighbour, Proxima Centauri, just 4 light-years away, they wouldn't reach it for another 80,000 years!
Attachments
I think it is a matter of scale.
At the scale of the solar system the sun is fixed.
At the scale of our galaxy, the galaxy has it' s own fixed medium in which stars are moving.
Andromeda and our galaxy are rushing to a front collision at a tremendous speed in some other fixed intergalactic medium.
At the scale of the solar system the sun is fixed.
At the scale of our galaxy, the galaxy has it' s own fixed medium in which stars are moving.
Andromeda and our galaxy are rushing to a front collision at a tremendous speed in some other fixed intergalactic medium.
- Status
- Not open for further replies.