Sunday 17 September 2017

Cassini, Future Missions, And The Paradox of Time-Travel


Jean Dominique Cassini 1625-1712 first discovered four of the moons of Saturn


Cassini is no more, a moment I watched with a glass of Absinthe - the cloudy liquid resembled the swirling atmosphere of Saturn - that was my excuse, anyway.
It lent a strange ambience to the last hour of the mission, and I sensed the bittersweet feels of those who had spent so much time on the amazing voyage of discovery.
But enough - I could go on at length, about how its discoveries had been attended and enabled by so many dedicated people that it really felt like the perfect antidote to world-weariness, how it left me with a sense of pride in the potential of our eternal curiosity, and thirst for knowledge.
With this in mind,further missions to Saturn and its moons are being considered, with two contenders earmarked for Titan and Enceladus, the possible life - bearing moons.
Here is a link to a pdf of the Cassini legacy
Sadly, the next proposed launch to Saturn is a few years away - but don't forget Juno is in orbit around Jupiter*, the next Mars probe will leave next year, and Bennu / Osiris- Rex is also already underway-the daring mission to collect and return with a sample from an asteroid.
Don't wait up for the sample - it won't be back on Earth until 2023.

Goldstone, which rec'd the signals from Cassini

Speaking of distant worlds (okay, that's a tenuous link), in a turnaround for the world of radio telescopes, it has been determined that Earth is in the visual sightline of at least nine exo-worlds, so they could be watching us...**
Pointless trivia perhaps, but it shows the sort of thing that occupies the mind of bored scientists.

Intrepid engineers at the University of New South Wales have developed the 'flip-flop' quantum qubit, which could be controlled electrically rather than magnetically, allowing for the speedy development of silicon - based quantum computers.
The most impressive aspect for me is the fact that the entangled particles can be manipulated whilst remaining entangled.

I decided that the occupants of the ISS are technically, time- travellers.

It transpires that time travel is possible, but only forward, really (to avoid all those pesky paradoxes  - as explored in films like Back To The Future- i.e.if you went back in time and killed your grandfather, then you would not be born so you couldn't travel back in time, etc)
To keep everything tidy, then, only future time travel is allowed.
Except, apparently, if you could manipulate a wormhole - then it would be theoretically possible to travel back in time, but only as far back as the beginning of the wormhole.
Could quantum entanglement be used to create a nano-wormhole between two entangled particles ?
I decided that whilst it may be possible in the quantum realm, it could never be upscaled for common use.
Then it was time to lie down quietly in a darkened room...


Until next time

G


* Jean Dominique Cassini was also first (with Robert Hooke) to observe the Great Red Spot on Jupiter

** It has already been pointed out to me that they would be looking at dinosaurs. Thank you, Pedantic Interwebbers