Voyager 1 is back online

[moorfield]

https://www.space.com/voyager-1-fully-operational

Hats of to these engineers, moving bits of software around 50 year old microchips from billions of miles away to get the instruments talking again - what incredible skills.

[GoSeigen]

Thanks moorfield.

I was amused that V1 was described as being in "uncharted territory", would love to see the map when it's finally completed.

Which made me think that space presumably is "normal" and what we experience living in close proximity to some big lumps of massy stuff is strange and exceptional. And I wondered, does space itself have any properties that we're aware of or is it defined entirely in contrast to the other things that we have detected: particles, photons, etc?


GS

[y0rkiebar]

Apparently it's just about to pass the last nail bar and Turkish barbers.

[DrFfybes]

William Shatner is quoted as saying "You're kidding, right? There's only 3 of us left, and we're getting too old for this ***"

[ReformedCharacter]

Which made me think that space presumably is "normal" and what we experience living in close proximity to some big lumps of massy stuff is strange and exceptional. And I wondered, does space itself have any properties that we're aware of or is it defined entirely in contrast to the other things that we have detected: particles, photons, etc?

GS

I suppose it's all a matter of scale but apparently the part of the universe that we inhabit is actually part of a huge void:

A growing list of observations suggests we live in the crosshairs of a giant cosmic void — the largest ever observed. Astronomers first suggested such a void in 2013 and evidence for its existence has been stacking up ever since.

https://www.businessinsider.com/we-live-inside-cosmic-void-breaks-cosmology-laws-2024-5

RC

[moorfield]

And I wondered, does space itself have any properties that we're aware of or is it defined entirely in contrast to the other things that we have detected: particles, photons, etc?

Dark matter, dark energy, the cosmological constant, the granular structure of space....?

[odysseus2000]

Thanks moorfield.

I was amused that V1 was described as being in "uncharted territory", would love to see the map when it's finally completed.

Which made me think that space presumably is "normal" and what we experience living in close proximity to some big lumps of massy stuff is strange and exceptional. And I wondered, does space itself have any properties that we're aware of or is it defined entirely in contrast to the other things that we have detected: particles, photons, etc?


GS

The vacuum energy is believed to exist throughout space in the entire universe:

https://en.m.wikipedia.org/wiki/Vacuum_ ... onstant%3F

This is a very complicated subject with the current belief that there is spontaneous matter anti matter creation that exists only for a time defined by the uncertainty principle in all vacuums. The origin of this is not, imho, well understood, along with many other things such as a matter dominated universe & the sea of negative energy states populated by anti particles being in the lowest energy states but antimatter can be created as in pair production when a sufficiently energetic (> 2 electron rest mass (511 keV) photon interacts near an atom to create a positron/electron pair. The atom has to be there to conserve momentum. This is an extremely common interaction, easily seen with a germanium detector, leading to a photon energy peak from the photo electric effect & two additional peaks each shifted down by 511 keV from the full energy & then from the other so that one has three peaks. Beneath that one also has the Compton background scattering. Anti matter was predicted by the Dirac equation which has a square root leading to plus & minus charge which Dirac didn’t initially worry about, then some thought the positive charge was the proton, but then in the 1930’s Carl Anderson measured positrons in cosmic ray experiments & they were identified as the +ve charged particle predicted by Dirac. Several years ago at CERN anti particles were measured & found to have the same mass as particles, acted upon by the same gravitational force, so they are anti matter only in charge & once they meet an electron they annihilate creating the two back to back 511 keV photons mentioned earlier.

Regards,