More science points!

[Rauko]

In ksp, when I send a sat, I put on it every single science gadget I have unlocked. What are the reasons it is not possible IRL? Economical? Weight? Others?

[UmbralRaptor]

The instruments are for fulfilling specific missions. (Exact type of instrument falls under the cost/weight issues you bring up, but first one needs a question to answer.)

[Superfluous J]

IRL there are almost literally an infinite number of science experiments that can be run. They put the ones on the probe that they think will give them the best bang for the buck, or that are there to find out specifically what they want to find out. And yes they put as many on as they possibly can.

If all they had were thermometers and barometers and things that detected graviolis then yes, they too would put every single science experiment available on every single craft they could.

Edited December 22, 2018 by 5thHorseman

[DDE]

On 12/22/2018 at 11:01 PM, Rauko said:

In ksp, when I send a sat, I put on it every single science gadget I have unlocked. What are the reasons it is not possible IRL? Economical? Weight? Others?

Sometimes temprature readings are just not valuable, there’s no such thing as Mystery Goo, and materials science is pretty indifferent to what you’re orbiting.

So every time you plan a mission you trim the list of instruments to those that would have utility. Furthermore, many such instruments are pretty picky about their manner of deployment (most notably, orbit), which restricts the range of selection even further. Some only have utility when targeting an atmosphere; others are blocked by an atmosphere.

If you want something closer to the IRL range of gadgets, look at DMagic Orbital Science and SCANSAT.

Edited December 24, 2018 by DDE

[pincushionman]

Also, since the scale of RL is 10x that of KSP, dV costs are accordingly higher. As a result, mass fractions for real craft are way, way worse. Compare the relative sizes of the Apollo/LM to the Saturn V, and a typical Mun lander to its corresponding launch vehicle; the extra constraints should be relatively apparent.

Compounding this is that while the spaceflight part of KSP is relatively accurate, the actual craft engineering is handwavey voodoo. Reaction wheels are overpowered, don’t saturate, and never fail, so we don’t need RCS most of the time or backups ever; solar panels always steer perfectly without wearing out; Kerbals don’t need food, water, air, or sufficient living space; that kind of thing. Getting materiel to other locations in the solar system is the easy part; getting it there and making sure it still works when it does is what’s difficult, expensive, and heavy.

[DDE]

2 hours ago, pincushionman said:

As a result, mass fractions for real craft are way, way worse.

Actually it cuts both ways. From what I understand, Kerbal rockets have an abysmally high share of dry mass, negating some of the dV advantage.