How dark is it within 40%-50% deep into Jupiter's radius?

Question

So lets say you have a flyby cam 40%-50% deep into Jupiter's radius (that's in the layer of liquid metallic hydrogen): Is it completely dark or are there enough lightnings and does Jupiter itself emit enough light in the visible spectrum to see at least somewhat roughly?

Answer 1

All objects glow due to their temperature- a phenomenon scientists call "black-body radiation".   In our day to day lives, however, this glow is not visible to us.   However, jf you could see in infra-red light (that is, light that is redder than the red we can see) you and I, simmering at human body temperature, would seem to dimly glow. (In fact, the military and police uses special equipment that pick up on this light that we cannot see with the unaided eye)  The warmer things get, the brighter they glow and the "bluer" they become.  

You can see this by doing an experiment:

Turn off all the lights in your kitchen at night.   Turn on your old fashioned electric oven burner and wait.  In a short while, you'll see the burner glow a very faint red.  As it heats up, its glow will become brighter and drift towards the orange.  If you had a mega-oven, capable of really high temperatures, your burner would, as it grew hotter and hotter, glow yellow, then white, and then blue-white, getting brighter all the while.  (It's a good thing ovens don't get this hot since your wallpaper would start to peel off and you'd get a heck of a sunburn from the ultra-violet light.)

What does this have to do with Jupiter?

If you could somehow survive the plunge deep into Jupiter's atmosphere, you would find the temperature slowly rising as pressures increased.  At the very center, the great gas planet is thought to be over 50,000 degrees F.  About halfway down, it's probably something close to half that.  However, 25,000 degrees F is more than enough to produce a brilliant blue white glow.    Given that the surface of the sun is only about 10,000 degrees F, that brilliant glow in the heart of Jupiter would appear brighter than our sun, and would to be coming from all directions.  Any lightning in the metallic hydrogen would be barely noticeable against all that glare.

Answer 2

Not sure, as no probe ever measured it.

According to the expected temperatures in that depth (10000K), it should emit significant black body radiation, but I don't know how emissive metallic hydrogen is. Liquid hydrogen is a clear liquid.