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Ursprungligen postat av
Denom
Det finns stoft och små partiklar utspritt i rymden också, det är inte helt tomt.
Du menar i solsystemet. Vi har asteroidbältet, och liknande.
Varje planet har antagligen fungerat lite som en dammsugare av partiklar, och dessa har väl kolliderat med varandra genom årmiljarderna vilket bildat själva planeterna såväl som dess månar.
Men ju längre bort från solen man kommer desto färre partiklar finns det kanske.... mänskligheten har trots allt byggt flera sonder som färdats ut i solsystemet, och en som lämnat solsystemet, utan problem med några kollisioner med partiklar, trots oerhörda hastigheter och oerhörda avstånd.
Citat:
Bortom Pluto finns Kuiperbältet, en region fylld med små isiga objekt som liknar Pluto. Efter det kommer Oorts kometmoln, som sträcker sig mycket längre ut i rymden. Det finns också andra planeter och objekt långt bort, men de är ännu inte fullständigt utforskade.
Citat:
Using information on the bombardment of quartz (silicon dioxide) and measurements of the interstellar gas concentration, the authors performed some calculations to describe the damage that will occur during flight. They found that while hydrogen and helium are the most common atoms the spacecraft will encounter, heavier atoms—specifically oxygen, magnesium, and iron—will do the vast majority of the damage.
Dust presents a somewhat different problem. Small dust particles will essentially act like a simultaneous bombardment by a lot of gas atoms. That's because the energy binding things together in a dust particle is tiny compared to the energy of the collision itself, and the dust is largely composed of heavier atoms. But a sufficiently large dust particle will create a collision energetic enough to destroy a craft. And "sufficiently large" isn't very big; the authors estimate that it only has to be 15 micrometers across to kill off the craft. Fortunately, dust particles this size are rare, and the authors calculate the odds of running into one at 10^50 to one against.
Overall, the authors find the effect of gas to be minor and only likely to cause damage down to a depth of 0.1 millimeters. Dust, however, is a different story. It will evaporate about 1.5 millimeters off the surface of the spacecraft, and melting will happen at depths of up to 10 millimeters. When every gram counts, this could be significant.
That said, the authors suggest a few potential ways to lower the impact of this problem. The simplest is to just limit the cross-section of the craft in the line of travel, which would involve folding the solar sail it relies on for its initial acceleration—and possibly placing it behind a shield. The main body of the craft could also be shaped a bit like a bullet in order to limit the area that presents a dust target.
