Q- Humanity's first interstellar flight pt 1

interstellar space travel is unmanned or manned travel between stars. The concept of interstellar travel in starships is a staple in science fiction. Interstellar travel is tremendously more difficult than interplanetary travel. Intergalactic travel, the travel between different galaxies, is even more difficult.

Many scientific papers have been published about related concepts. Given sufficient travel time and engineering work, both unmanned and generational interstellar travel seem possible, though representing a very considerable technological and economic challenge unlikely to be met for some time, particularly for manned probes. NASA has been engaging in research into these topics for several years, and has accumulated a number of theoretical approaches.

The main difficulty of interstellar travel is the vast distances that have to be covered. This means that a very high speed and/or a very long travel time is needed. The time it takes with most realistic propulsion methods would be from decades to millennia. Hence an interstellar ship would be much more severely exposed to the hazards found in interplanetary travel, including hard vacuum, radiation, weightlessness, and micrometeoroids. The long travel times make it difficult to design manned missions, and make a primarily economic justification of any interstellar mission nearly impossible, since benefits that do not become available for decades or longer have a present value close to zero.[quantify]

A significant factor contributing to the difficulty is the energy which must be supplied to obtain a reasonable travel time. A lower bound for the required energy is the kinetic energy e = ½ mv2 where m is the final mass. If deceleration on arrival is desired and this cannot be achieved by an atmosphere then the required energy is even more.

The velocity for a manned round trip of a few decades to even the nearest star is thousands of times greater than those of the present space vehicles. This means that due to the square law, millions of times as much energy is required. Accelerating one ton to one-tenth of the speed of light requires at least 450 PJ or 4.5 × 1017 J or 125 billion kWh, not accounting for losses. This energy has to be carried along, as solar panels do not work far from the Sun and other stars.

There is some belief that the magnitude of this energy may make interstellar travel impossible. It is reported that at the 2008 Joint Propulsion Conference, where future space propulsion challenges were discussed and debated, a conclusion was reached that it is improbable that humans will ever explore beyond the Solar System. Brice N. Cassenti, an associate professor with the Department of Engineering and Science at Rensselaer Polytechnic Institute, stated At least 100 times the total energy output of the entire world would be required for the voyage (to Alpha Centauri) [1]

A major issue with traveling at extremely high speeds is that interstellar dust and gas may cause considerable damage to the craft, due to the high relative speeds and large kinetic energies involved. Various shielding methods to mitigate this problem have been proposed[citation needed]. Larger objects (such as macroscopic dust grains) are far less common, but would be much more destructive. The risks of impacting such objects, and methods of mitigating these risks, have not been adequately assessed[citation needed].

It has been argued[by whom?] that an interstellar mission which cannot be completed within 50 years should not be started at all. Instead, the money should be invested in designing a better propulsion system. This is because a slow spacecraft would probably be passed by another mission sent later with more advanced propulsion.[2] On the other hand, Andrew Kennedy has shown [3] if one calculates the journey time to a given destination as the rate of travel derived from growth (even exponential growth) increases, there is a clear minimum in the total time to that destination from now. This is significant because voyages undertaken before the minimum will be overtaken by those who leave at the minimum, while those who leave after the minimum will never overtake those who left at the minimum. Any civilization traveling to an interstellar destination can look forward to a unique date that is best to leave, and one that is the most efficient with cost and time.

Intergalactic travel involves distances about a million-fold greater than interstellar distances, making it radically more difficult than even interstellar travel.

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[hellspawnds]

Narrator sounds horny

[AgrivatedKillah]

@GhostHunter1986 You're an idiot, they don't have the tech. If they had the tech..the person who came up with the means to travel would be the worlds richest person.

[Helge129]

@intushabitat It's not mathematically neglible. Light - that includes radio waves - is extremely fast, and only takes a fraction of a second to go between the GPS device and the sattelites. The distance, and thus possition, is calculated by how long the signal takes between 3 sattelites and the GPS device. The temporal effects due to the sats's distance from Earth and their speed need to be taken into account, or you get wrong distances and possitions.

[intushabitat]

@Helge129

Here's lorentz contraction equation: lo=l * square root of ( 1- v2/c2)

do the calculation to any given length and at these low speeds ull find it mathematically negligible

[Helge129]

@intushabitat I forgot to mention: Time dilation has very real effects. It has to be taken into account with GPS, else it gives wrong positional data.

[Helge129]

@intushabitat 150000 mph through unpowered gravitational slingshot. By unpowered I mean, its engines didn't accelerate it to that speed.

Matter can travel at that speeed.

[intushabitat]

@Helge129

I shouldn't have refered to time as a constant. it was just a joke.

[intushabitat]

@Helge129

Time dilation is negligible for common speeds. for that to happen a body has to travel at a speed very close to the speed of light. That's energy beyond one's wildest imagination.

1- Can matter travel at that speed?

2-Whats the record speed of a spacecraft? I'm not sure but I think it was Helios I & II 150,000 MPH

with these in mind , i believe time dilation in practice is surrealistic.

[Helge129]

@intushabitat That's actually wrong. It would get there in a few years, due to time dilation.

[Helge129]

@xenathegoat Yes, it is a human narrating it.

[xenathegoat]

that's not a human narrating. that's one of those computer voices. geez

[Th3Shadow0fDeath]

@AgrivatedKillah man the elliet are going to get you if you keep insulting ghost hunter's obviously very large intellect