ACCELERATE TO THE PLANETS
G-force to the planets in days.
CONSIDER THOUGHT EXPERIMENT:
Let a notional spaceship
accelerate at rate g (10 m/sec²)
between points within the Solar System.
Let a notional spaceship
accelerate at rate g (10 m/sec²)
between points within the Solar System.
During first half of journey,
g-force vessel gains so much speed,
that it must g-force decelerate
during second half.
g-force vessel gains so much speed,
that it must g-force decelerate
during second half.
Nicholas Copernicus (1473-1543) postulated the Sun as the center of the Universe. Born in Torun, Poland, Copernicus first studied astronomy and astrology at the University of Cracow (1491-94). After considerable more study in mathematics, medicine and law; he returned home for an extremely fruitful life. In 1514, he began to circulate in manuscript the 'Commentariolus' (A Brief Description), in which he criticised then prevalent Ptolemaic system for not adhering to the principle of uniform circular motions and offered instead his own system in which the earth and all the other planets rotate around the sun. By the 1530s, Copernicus's reputation as a skilled mathematician had even reached the ears of the Pope. Thus, the distinguished Professor Georg Joachim Rheticus (1514-1574), University of Wittenburg, included Copernicus on a tour of distinguished scholars and visited Copernicus in 1539. Thus, Rheticus reported Copernicus' heliostatic theory in his subsequent book, Narratio Prima (First Report on the Books of Revolution) in 1540 at Gdansk. Following the favourable reception of the Narratio Prima, Rheticus persuaded Copernicus to publish a full account. This became the De Revolutionibus Orbium Coelestium. | Of course, we currently use non-powered spacecraft to orbit throughout the Solar System. They routinely travel between planets via "transfer orbits", which take months and years. Furthermore, interplanetary trips must be timed to accommodate planetary positioning; such synchronization requirements can add years of further delay. Thus, human transport via transfer orbit is infeasible, and practical payloads are limited to Artificial Intelligence (AI) devices. Transfer orbits between planets at constant velocity will take months and years. This might work for robots and other AI devices; it probably would not work so well for humans. On the other hand, g-force spacecraft would enable humanity to routinely travel between planets within days. Such vessels would no longer be constrained to transfer orbits, and humans could routinely transit the planets in days and weeks. |
G-force acceleration will quickly take the vessel to enormous speeds; thus, such voyages must observe a flight profile:
| Copernicus ordered the planets and proposed the universe to be centered on Sol (our sun) versus Terra (our Earth) then considered as the center of the universe. Thus, Copernicus is often incorrectly portrayed as a controversial figure who advocated a heliocentric system for the express purpose of overthrowing existing systems and institutions. In fact, his monumental work follows parameters and data from Ptolemy, and it's even dedicated to the Pope in a fashionable style. He presents a model in which the earth rotates daily and orbits the sun, but the sun itself was not quite in the center of the universe. He established the order of planets and devised a system which accounted for the movements of planets without equants, but he was motivated by the desire to establish uniform circular motion, itself a classical ideal. Copernicus certainly believed that this was the true system of the physical universe, but this conviction was not shared widely by his peers for contemporary reasons. "On the Revolutions of the Heavenly Spheres" was published in March 1543 at Nuremberg. Copernicus died two months later. (For more.) |
EXAMPLE: After only 3.16 days, we reach midway (2.5 AU) of our 5 AU journey to Jupiter.
Max speed is at midway; vessel must slowdown for 2nd half.
|
Then, compute acceleration time: tAcc = √(2 × dAcc/g) = √(d/g) Finally, compute max velocity: VMax = tAcc × g | |||||||||||||||||||||||||||||||||
| 1) Since g-force vessels can travel AUs in days, describe acceleration value as g=.5 AU/day², a value very close to 10 m/sec2. 2) Vessel increases speed 864 kilometers per second (kps) for each day of g-force acceleration; thus, g = 864 kps/day. |
Accelerate to Very High Velocities. v = g * t = 864 km/sec per day. With constant g-force acceleration, vessel increases speed to several hundred times Earth's escape velocity (e = 11 km/sec). This is way too fast to do anything useful at our interplanetary destination; thus, the spacecraft must SLOW DOWN!!!
Thus, we need PHASE II. G-FORCE DECELERATION FROM MIDWAY TO JUPITER
|
---|
Typical | Accelerate | Max Velocity | Decelerate | Total | ||
---|---|---|---|---|---|---|
Dist. fm Earth | Dept to Midway | (at midway) | Midway to Dest | Travel Time | ||
d | dAcc | tAcc | VMax | tDec | tTtl | |
NEO |
1 AU
|
0.5 AU
|
1.4 dy
|
1,218 km/s
|
1.41 dy
|
2.83 dy
|
Mars |
2 AU
|
1.0 AU
|
2.0 dy
|
1,728 km/s
|
2.00 dy
|
4.00 dy
|
Jupiter |
5 AU
|
2.5 AU
|
3.2 dy
|
2,730 km/s
|
3.16 dy
|
6.32 dy
|
Saturn |
10 AU
|
5.0 AU
|
4.5 dy
|
3,864 km/s
|
4.47 dy
|
8.94 dy
|
Uranus |
20 AU
|
10 AU
|
6.3 dy
|
5,464 km/s
|
6.32 dy
|
12.64 dy
|
Neptune |
30 AU
|
15 AU
|
7.8 dy
|
6,693 km/s
|
7.75 dy
|
15.50 dy
|
Given | d / 2 | √(d/g) g= 0.5AU/day2 | tAcc×g g=864kps/day | √(d/g) tDec = tAcc | 2×√(d/g) tTtl = tDec + tAcc |
SUMMARY: Given the proper planetary alignment, a typical transfer orbit could take 7 months to travel to Mars. However, our thought experiments contends that g-force acceleration could reduce the travel time to a few days to any of the nearby planets.
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