they could use the very thick atmosphere as the surface of the olanet, wich is gas. Then the planet would be out of atmosphere and that would be gas than. So you would fly through Jupiter realistical.
that's from wikipedia:
Jupiter is 2.5 times the mass of all the other planets in our Solar System combined—this is so massive that its barycenter with the Sun lies above the Sun's surface at 1.068 solar radii from the Sun's center. Although this planet dwarfs the Earth with a diameter 11 times as great, it is considerably less dense. Jupiter's volume is equal to 1,321 Earths, yet the planet is only 318 times as massive.[5][21] Likewise, Jupiter has a radius equal to 0.10 times the radius of the Sun,[22] but is only 0.001 times the mass of the Sun.[23] A "Jupiter mass" (MJ or MJup) is often used as a unit to describe masses of other objects, particularly extrasolar planets and brown dwarfs. So, for example, the extrasolar planet HD 209458 b has a mass of 0.69 MJ, while CoRoT-7 b has a mass of 0.015 MJ.[24]
Theoretical models indicate that if Jupiter had much more mass than it does at present, the planet would shrink. For small changes in mass, the radius would not change appreciably, and above about four Jupiter masses the interior would become so much more compressed under the increased gravitation force that the planet's volume would decrease despite the increasing amount of matter. As a result, Jupiter is thought to have about as large a diameter as a planet of its composition and evolutionary history can achieve. The process of further shrinkage with increasing mass would continue until appreciable stellar ignition is achieved as in high-mass brown dwarfs around 50 Jupiter masses.[25] This has led some astronomers to term it a "failed star", although it is unclear whether the processes involved in the formation of planets like Jupiter are similar to the processes involved in the formation of multiple star systems.
Although Jupiter would need to be about 75 times as massive to fuse hydrogen and become a star, the smallest red dwarf is only about 30 percent larger in radius than Jupiter.[26][27] Despite this, Jupiter still radiates more heat than it receives from the Sun. The amount of heat produced inside the planet is nearly equal to the total solar radiation it receives.[28] This additional heat radiation is generated by the Kelvin-Helmholtz mechanism through adiabatic contraction. This process results in the planet shrinking by about 2 cm each year.[29] When it was first formed, Jupiter was much hotter and was about twice its current diameter.[30]
(
http://en.wikipedia.org/wiki/Jupiter#Mass)
Ok the Gravity isn't proportional to the mass because you are more far away from the center of mass on a bigger planet, but recognize: 96 is very less than that 1,321x318.
I read that 96 at some very reliable texts and in Orbiter jupiter has really a very more mass than earth:
earth:
; === Physical Parameters ===
Mass = 5.973698968e+24
;Size = 6.378165e6 ; equatorial radius
Size = 6.37101e6 ; mean radius
JCoeff = 1082.6269e-6 -2.51e-6 -1.60e-6 -0.15e-6
; harmonic coefficients for shape description
Jupiter:
; === Physical Parameters ===
Mass = 1.8986111e+27 ; mass [kg]
Size = 6.9911e+7 ; mean radius [m]
JCoeff = 0.01475 ; J2 coefficient for gravitational potential
AlbedoRGB = 2.02 1.99 1.86
