What is the distance traveled in meters by light in one Leap year?

Answer 1

Light travels at 300,000 km/sec or 3*10^8 m/s. Thus 1 light second= 3*10^8 m 1 light minute=1.8*10^10 m, or 18 billion meters, (18 gigameters), 18 million km, 11.1 million miles The Sun is 8.4 light minutes from earth. 1 light hour= 1.08*10^12 m, 1.08 trillion meters, (1.08 terameters) 1.08 billion kilometers, 667 million miles 1 light day=2.59*10^13 m, 25.9 terameters, 25.9 billion km, 16 billion miles 1 light year= 9.47*10^15 m, 9.46 petameters, 9,460 terameters, 9.46 trillion km, 5.84 trillion miles. The nearest star is Alpha Proximi, 4 light years away or 23.4 trillion miles from earth. If you could drive there at 60 mph it would take 4.45*10^7 years, 44.5 million years The fastest humans were the Apollo astronaughts, who reached 25,000 mph, it would take them 106,849 years to get Alpha Proximi. 1 parsec is 3.27 light years, =3.1*10^16 m, 31 petameters, 310 trillion km, 191.35 trillion miles. The nearest possible earth like planet, Gliese 581 C, is 20.5 light years, or 6.3 parsecs away. Useing today's conventional chemical rockets, (25,000 mph) it would take 547,198 years to get there. Using fusion rockets that can achieve speeds of .5c (50% the speed of light) it would take 41 years as viewed from earth, (at such relativstic speeds time would slow down for anyone inside the rocket, so it would seem as if 35.5 years had passed). At .75c the trip to Gliese 581 C would take 27.3 years as seen from earth, 18.1 years elapsed inside the rocket. At .9c (the realistic limit for even the most advanced antimatter powered space ships due to the exponentially larger energy requirements needed to speed up as you approach the speed of light) the trip would take 22.8 years as seen from earth, for those inside the ship 9.9 years would have passed. Thus it is clear that only 4 possibilities exist for humans reaching other earth like planets, (10 years away is the closest possible earth like planet, most others will be centuries or millenia away) 1. Discover how to travel faster than light by warping space, theoretically possible but the energy requirements are too great for this to be practical, most likely faster than light travel is impossible. 2. Advance medicine to the point where we can slow or stop aging and give humans life spans measured in centuries of millenia. 3. Develop a way to put humans in suspended animation. 4. Build generational ships where several generations of people are born, work and die, while in transit. Also note that due to time dilation effects, (time slows down as you travel at higher velocities) at .9c velocity for each 1 year that passes on the ship 2.33 years passes on earth. So interstellar empires are impossible, since it would take decades or centuries to communicate with other planets, and even visiting earth from Gliese would mean arriving decades into the future, from the perspective of someone onboard a ship coming to earth. Thus any colonists leaving earth would almost certainly be making a 1 way trip.