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2 hours ago, NewBornBairn said:

I’ve always thought that the problem with time travel is that the Earth moves through space at 67,000mph whilst spinning at 1,000mph at the equator. 
Even if you calculate the travel in the other three dimensions correctly, misjudging your time jump by just a few milliseconds could have you rematerialising in the middle of a wall.

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16 hours ago, RandomGuy. said:

Ended up reading about this the other day...

... don't know nearly enough to know exactly what it was all about (scientists got all excited because a previously thought impossible black hole in terms of mass/size seemed to form in front of them after two collided), but it makes you feel pointless.

Apparently the two black holes collided 7 billion years ago, and the signal only reached Earth in May last year. The sheer size and scope of everything is terrifying.

"Space is big. Really big. I mean you might think it's a long way to go to the shops but that's peanuts compared to space"

The Hitchhiker's Guide to the Galaxy.

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https://edition.cnn.com/2020/11/02/world/space-station-20th-anniversary-continuous-human-presence-scn-trnd/index.html

20 years of continuous human occupation of space today. 

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On 28/10/2020 at 07:02, RandomGuy. said:

Ended up reading about this the other day...

... don't know nearly enough to know exactly what it was all about (scientists got all excited because a previously thought impossible black hole in terms of mass/size seemed to form in front of them after two collided), but it makes you feel pointless.

Apparently the two black holes collided 7 billion years ago, and the signal only reached Earth in May last year. The sheer size and scope of everything is terrifying.

It caused a huge buzz, in part due to the size of it and in part as you said its in a region of black hole sizes that we currently think cannot be come directly from a star exploding. This means either it had already absorbed another black hole or that our understanding of really giant stars is wrong. If its the former then its kind of exciting as this is how we think the supermassive black holes at the centre of galaxies form. If its the latter then we may need to rewrite how really massive stars die. They are important as this is where we get the heaviest elements from. 

In terms of its size its beyond mind blowing. Two black holes, one 85 and one 66 solar masses in weight absorbed each other. This created a black hole 142 solar masses. 66+85 = 151. As the black holes approached each other they released huge amounts of energy distorting spacetime. The equivalent of about 8-9 solar masses. Gravity waves are the only way you can get mass out of a black hole (other than Hawking Radiation). These are very very rare events as we observe them. In the early universe it was probably common when galaxies were forming. 

What we think happens is two black holes orbit each other over millions to billions of years. They give off small amounts of energy as gravity waves and this allows them to spiral closer together. When they creep close enough the energy loss rises exponentially and they start closing in at faster and faster speeds, their orbits approach very high speeds. To put it into perspective the event horizon of the 85 solar mass black hole would be about 250km. 

When they close enough this is when you get the energy of about 8 solar masses released in a second or so. As others have said its incredibly far away. Although it was 7 billion years ago, it was 17 billion light years away due to expansion of the universe. That means the energy release is a sphere of distorted spacetime 17 billion light years in radius and travelling outwards. 

In other news, Roger Penrose won a joint Nobel Prize this year for the maths showing black holes were very likely real. Jointly shared with Andrea Ghez and Reinhard Genzel for discovering the supermassive black hole at the centre of our galaxy (its sort of linked to what I said above). 

Generally been a great year for black hole science (unlike 1994 which was a good year for Black Hole Sun). 

 

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Space X has a crew launch for the ISS tomorrow. Its notable in being the largest crew ever flown on a non Shuttle vehicle, 4. 

Also looks like Artemis is slipping and may end up 2026 before we get a Moon landing. This will start pushing it to when the ISS is due to retire. The current plan is to change to being a commercial research platform without the Russian modules. 

In other news Angara is (finally) due to launch. Its a new Russian launch vehicle but was supposed to fly in the early 90s. It looks like there space program is headed to deep trouble in the coming decade. Commercial geostationary communications satellites are on hold as the industry waits to see if Starlink and OneWeb have an impact on their markets, China is doing its hugely subsidised effort to become a player and off course Space X is eating everything up that is not Arainespace or can fly on a China launch (US restricts technologies they an access so a lot of comms and other stuff cannot fly Chinese). And their big money spinner, the ISS is approaching end of life. 

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A SpaceX Falcon 9 Block 5 rocket will lift off from LC-39A, at the Kennedy Space Center, carrying three NASA astronauts and one JAXA astronaut to the ISS. This mission, Crew-1 (USCV-1), will mark SpaceX’s first operational crewed launch as part of the Commercial Crew Program. Crew-1, or USCV-1, will mark the first regular crew rotation mission that is launched on top of a SpaceX Falcon 9 rocket. SpaceX’s Crew Dragon will carry four astronauts to the International Space Station for their six months stay. This launch will bump up the number of crew on the ISS to seven. They will join NASA astronaut Kate Rubins and Roscosmos cosmonauts Sergey Ryzhikov and Sergey Kud-Sverchkov on November 15, just 8.5 hours after launch.

Live on YOUTUBE.

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Take off at 0027, weather permitting. Coverage ongoing.

 

Edited by welshbairn

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17 minutes ago, welshbairn said:

The door won't close, anyone got a jemmy?

I’m sure one of them can just hold it shut till they get up there?

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9 minutes ago, Melanius Mullarkey said:

I’m sure one of them can just hold it shut till they get up there?

Aye, it will be good if they can find something to keep the woman occupied before dinner time. 

Edited by welshbairn

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Whacky weather satellite Sentinel-6 Michael Freilich getting launched 1717 on Saturday on another Falcon 9 rocket.

Sentinel-6-Michael-Freilich-radar-altime

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On 15/11/2020 at 23:44, welshbairn said:

Whacky weather satellite Sentinel-6 Michael Freilich getting launched 1717 on Saturday on another Falcon 9 rocket.

Sentinel-6-Michael-Freilich-radar-altime

Going up.

 

 

Edited by welshbairn

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13 minutes ago, welshbairn said:

Going up.

 

 

Interesting bit on beeb website about it mapping sea levels. So it isn't global wide raises, but localised.

 

The data I would read for days when it hits.

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1 hour ago, Manifesto said:

Interesting bit on beeb website about it mapping sea levels. So it isn't global wide raises, but localised.

 

The data I would read for days when it hits.

One of the boffins explained that the reason 3mm sea rise a year (accelerating, now approaching 5mm) is something to worry about, is that it's like gallon buckets of water stacked up to Pluto and back being added to the oceans every year. Not sure how significant that is but it's vivid. Light takes 5 1/2 hours to get to Pluto.

If you have time to spare here's the journey on a light speed capable ship.

 

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23 minutes ago, welshbairn said:

One of the boffins explained that the reason 3mm sea rise a year (accelerating, now approaching 5mm) is something to worry about, is that it's like gallon buckets of water stacked up to Pluto and back being added to the oceans every year. Not sure how significant that is but it's vivid. Light takes 5 1/2 hours to get to Pluto.

If you have time to spare here's the journey on a light speed capable ship.

 

That was the point of the article.

 

Stats like that are misleading.

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