Duration: flights to L-4 point, and 90 degrees Earth orbit

In summary, a spacecraft with the same mass but dimensions reflecting the change in shape transports people and cargo to locations near and far, using a direct line of flight. It has a capacity of 564,763 kilograms.
  • #1
Fred Bobo
15
0
Assumptions:
200+ years from now
Asteroids have been moved to all Lagrange points, and at least 90, 180, and 270 degrees on Earth's' orbit for mining, and shielding humans and equipment
Tech to acceleration/decelerate at 1 gravity without need to carry fuel. (My main fiction.)
Direct line of flight

Space craft, tube shape, with decks perpendicular to line of flight.
Transport of crew, passengers, cargo: supplies, heavy tools,...

Mass: Similar to the Mont Oil Tanker(Knock Nevis, Jahre Viking, Happy Giant, Seawise Giant)
General Characteristics:
Tonnage: 260,941 GT (214,793 NT)
Length: 458.45 m (1,504 ft)
Beam: 68.8 m (226 ft)
Draught: 4.611 m (81 ft)
Capacity: 564,763 WT

Same mass, but dimensions reflecting the change in shape: Shorter length and larger diameter.

I am most interested in the duration of trips to the L4 point, and to 90 degrees forward Earth orbit,...Including the time to ramp up to 1g, the length of midpoint turnover, and the deceleration period.

Flights to all Lagrange points and to Mars L-points,... are of interest.
 
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  • #2
Fred Bobo said:
Including the time to ramp up to 1g, the length of midpoint turnover
This depends on your fictional method to accelerate.

L4 and L5 are 1 AU = 150 million km away, at a constant 1 g acceleration you can ignore orbital mechanics because you are much faster anyway. At a=1g you need ##T=\sqrt{2d/a} = 120,000 s = 34 h## to the midpoint and the same time afterwards, for a total of 68 hours or nearly three days (72 hours). Peak speed is 1200 km/s or 0.4% the speed of light.
 
  • #3
Thank you.

would there not be a period of ramp up that will not exist at the end? Trying to visual.

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how about L1-3 and the moon for a craft 1/10-20th the size? Daily/hourly transports to the destinations within a 24 hour duration.

================

I really wish i knew how to create a spread sheet with all the correct formulas.
 
  • #4
Also: what do think the minimum acceleration should be to maintain human body health?

I think long hauls will be best to be at 1g. Shorter trips, even repeated often, will be less injurious. Or else not.
 
  • #5
Fred Bobo said:
would there not be a period of ramp up that will not exist at the end? Trying to visual.
That depends on how your magic drive works. If it needs an hour or more to reach 1g then the trip gets a bit longer.

Chemical rockets can start within about a second.
Fred Bobo said:
how about L1-3 and the moon for a craft 1/10-20th the size?
Just plug in different values for d (half the length). a=10 m/s2.We don't know the effect of reduced gravity on humans for a long time. We know 0 g for a long time is not so good, we know 1 g is good. For a few days it doesn't matter.
 
  • #6
mfb said:
That depends on how your magic drive works. If it needs an hour or more to reach 1g then the trip gets a bit longer.

Chemical rockets can start within about a second.Just plug in different values for d (half the length). a=10 m/s2.We don't know the effect of reduced gravity on humans for a long time. We know 0 g for a long time is not so good, we know 1 g is good. For a few days it doesn't matter.

Thank you. more to think about.
 
  • #7
I'm not entirely sure you know what the terms you're using mean. Could you define (or better still, look up), please...

- 1 gravity acceleration : and what it means in terms of speed/velocity, and if there's a relation to mass/weight.
- ramp up
- turnaround : what it is and why it's used.
- LaGrange/LaGrangian/L points. (I'd suggest Wikipedia "LaGrangian points")

Basic kinematics formulae for distance, time, acceleration are also in Wikipedia (or here, it's a sticky post somewhere).

As DaveC points out, if you're going from Earth to L4 or L5, or other planets, at 1g, you don't have to worry much about orbital mechanics, because you're going (averaging) too fast for it to make much a difference, in an SF story where you'll presumably be saying "a few days" or "a couple of hours".

For messing about around the Earth<>Moon system, the grav sources are right in your face and the times are short (so massive velocities aren't built up), so yeah they'll make a difference there, as well as maybe throttling back a bit for passenger comfort in various circumstances.
 

Related to Duration: flights to L-4 point, and 90 degrees Earth orbit

1. What is the duration of a flight to the L-4 point?

The duration of a flight to the L-4 point, also known as the Lagrange point 4, varies depending on the spacecraft's speed and trajectory. On average, it takes about 3-4 days for a spacecraft to reach the L-4 point from Earth.

2. How long does it take to reach a 90 degree Earth orbit?

The duration of a flight to a 90 degree Earth orbit also depends on the spacecraft's speed and trajectory. On average, it takes about 1-2 days for a spacecraft to reach a 90 degree Earth orbit from Earth.

3. What factors affect the duration of a flight to the L-4 point?

The duration of a flight to the L-4 point can be affected by various factors, such as the spacecraft's speed, trajectory, and the gravitational pull of other celestial bodies. The presence of space debris and solar activity can also impact the duration of the flight.

4. How does the duration of a flight to the L-4 point compare to other space missions?

The duration of a flight to the L-4 point is relatively short compared to other space missions, such as missions to the Moon or Mars. This is because the L-4 point is relatively close to Earth, making it easier and quicker to reach.

5. Can the duration of a flight to the L-4 point be shortened?

Yes, the duration of a flight to the L-4 point can potentially be shortened by using more powerful propulsion systems or by taking advantage of gravitational assists from other celestial bodies. However, these methods may also require more resources and planning.

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