Space Mysteries

Space Mysteries

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Space Mysteries

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Presentation Transcript

1. Space Mysteries • Chris Egbert • Jon Pruett

2. If you were in space… Would this really happen?

3. The Idea • Hollywood films have always incorporated science in their productions. However, the question that always seems to arise is, how accurate are these scientific features? • The clip shown, from the movie “Mission to Mars” depicts a body that is instantly frozen in space. Using knowledge acquired in Heat Transfer class, our group will demonstrate the accuracy of the scene.

4. Known Values • G=1380 W/m2 (solar flux near earth) • skin=0.97 • skin=0.62 • kskin=0.37 W/m.K • =1000 kg/m2 (assume water) • Cp=4201 J/kg.K (assume water) • T=0 K • T0=310 K • D= 0.2 m (assume head only)

5. Equations •  Ts4 As=G Ac Ts=(G/4)1/4 space = 250k = -23ºC •  (Ts4 - T4)= Ts- T h=  Ts3 =0.86 W/m2.k • Bi=hD/6k =0.08 (use lumped) • T (273)=Cp/h . V/As ln (T-To/ T-T) =5.75 hrs. Disproved

6. Conclusion • This is one of the many science flaws found in Hollywood film. • Tune in next semester for another thrilling… SPACE MYSTERIES