Recent comments in /f/askscience

tomsing98 t1_j1t1uqj wrote

Reply to comment by Racklefrack in Why are there deserts near the coast? How come they don't get more rain, despite being near to a large body of water with plenty of sun and evaporation? by milton117

To expand on the rain shadow effect - air going up over a mountain range cools and water condenses out of the air, falling as precipitation. Then as it comes down over the opposite side, it warms back up and is at much lower humidity (since it lost water as precipitation, and since warm air can hold more water). So you're going to get much less condensing water/clouds/precipitation on the back side of the mountain range. If you have a prevailing wind such that this is mostly happening in the same direction, you'll have a rain shadow desert.

You can even get rain shadow deserts over the ocean, on the lee side of a mountainous island.

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athomasflynn t1_j1t1fgy wrote

Reply to In Sci-Fi the concept of eye-transplants is common enough - what would it take to actually be able to do it? by Daniel_Jacksson

We would need the ability to graft and/or regrow nerve tissue. Something has to carry the visual signals generated by the eye to the brain or its just a useless eye sitting in your head.

For an artificial eye (basically just a camera) we would need the ability to connect and interface electronic components with nerve tissue and the receiver would need to be able to produce a signal that the brain can understand.

We will probably have eye transplants well before bionic eyes. When we do, what you're describing is basically something like a Bluetooth receiver connected directly to the optic nerve where the "eye" is a standalone, battery powered camera that just happens to sit in the eye socket most of the time. Useful, but it would probably be really disorienting when you take it out. I imagine most people would get motion sickness.

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Racklefrack t1_j1t0l23 wrote

Reply to Why are there deserts near the coast? How come they don't get more rain, despite being near to a large body of water with plenty of sun and evaporation? by milton117

One example is Nevada, which is relatively near the Pacific and is mostly desert or very desert-like, it sits in the "rain shadow" of the Sierra Mountains along the CA / NV border, hence, much less rain = desert.

There are probably dozens more explanations for other deserts both nearby and around the world.

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Dramatic-Move8793 t1_j1stzyf wrote

Reply to What happens if a mother‘a child has a non-compatible blood type? What will happen when she is pregnant? by thebookklepto

If the mother has Rh negative blood and becomes pregnant with a baby who has Rh positive blood, the mother's body will see those Rh antigens as foreign particles and will try to fight it off. Typically the first pregnancy is okay. But the mother's body will have built up an immunity against the Rh antigen by the second pregnancy.

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