Water found on a potentially life-friendly alien planet

Post by rhinoceraptor » Wed, Sep 11, 2019, 10:21 PM UTC

partiallypro wrote: post #89

sky_rw wrote: post #76

Earlier quoted context omitted.

Not sure the two are comparable. 300lb obese person's bone structure weighs the same, their heart and lungs weigh the same. I suspect 2x the weight on every organ is going to be seriously detrimental for sustained periods.

Not to mention you'd go from years and years of near 0G gravity to twice the gravity of earth. You wouldn't even be able to walk.

Post by PorterDuff » Wed, Sep 11, 2019, 10:23 PM UTC

SJSque wrote: post #17

transreal wrote: post #2

With a planet this large, visiting it would be a one way trip due to the "The Tyranny of the Rocket Equation" [0]. I'm looking forward to the day we start finding exo-planets that are closer to Earth in size and which could potentially have space-faring races (and which we could leave if we were ever to visit them). [0] - https://www.nasa.gov/mission_pages/station/expeditions/exped...

There's also the Wait Calculation to consider: https://en.wikipedia.org/wiki/Interstellar_travel#Wait_calcu...

Post by isostatic » Wed, Sep 11, 2019, 10:23 PM UTC

akiselev wrote: post #41

ta1234567890 wrote: post #29

Earlier quoted context omitted.

Exactly From the reference article: > Travelling from the surface of Earth to Earth orbit is one of the most energy intensive steps of going anywhere else. This first step, about 400 kilometers away from Earth, requires half of the total energy needed to go to the surface of Mars. Which means that if we use something like a balloon/blimp in the first stage, it would be a lot more energy efficient. Anyone knows why it…

The Pegasus rocket used to launch satellites from a modified 747 for between 1990 and 2016 [1]. It just doesn't work out well in practice because the cost of the modified plane far exceeds the cost savings from a first stage unless you're doing half a dozen or more launches per year. [1] https://en.wikipedia.org/wiki/Pegasus_(rocket)

Post by typeformer » Wed, Sep 11, 2019, 10:24 PM UTC

brlewis wrote: post #113

typeformer wrote: post #94

Earlier quoted context omitted.

The government has been studying UFO's at the highest levels since at least 1947 and likely prior. You don't study something closely for 7 decades and not learn anything. https://www.cia.gov/library/center-for-the-study-of-intellig...

OK let me see if I understand the chain of inference here. The government has been studying UFOs for 7 decades ==> The government has learned something ==> The government has acquired alien technology I'm mostly with you on that first arrow, but you lost me on the 2nd.

Post by charlesju » Wed, Sep 11, 2019, 10:24 PM UTC

0xffff2 wrote: post #124

kadoban wrote: post #122

Earlier quoted context omitted.

It would not take 4 billion years at the speed of light, it would take 111 years. That's what light-years are, the distance travelled by light in a year.

Strictly speaking, if you actually traveled at the speed of light , the trip would be instantaneous from the reference frame of the craft making the trip. It would still take 111 years from our frame of reference on Earth.