Does light refract when entering the Earth's atmosphere? If so, how different is the view on Earth than in space?
Yes, light does refract in earths atmosphere in much the same way way the view of asphalt is distorted on a hot summer day. Now the view on earth is basicly exactly the same as in space, but with some minor differences. First off the stars do not twinkle in space, this is because the stars from earth are refracting through the turbulent atmosphere. This is also one of the reasons why the Hubble space telescope is able to take such clear images of galaxies and nebulae, no atmosphere to get in the way. Another difference is that space is much darker than the darkest places on earth, so you could see many distant objects with the naked eye that would not be possible in a city on earth. The milky way, the andromeda Galaxy, bodes Galaxy, uranus, the zodiacal lights, would all be visible in the zero light pollution of space.
Hope this helps
It does indeed. Radio waves are not affected so much though, so try this little experiment.
Take an AM radio and tune it off station. All you will get is static.
Go out before dawn. Static.
The Sun will be below the horizon but dawn is Just brightening the sky. Static.
The Sun just starts to appear on the horizon. Static.
The Sun rises higher but has yet to fully clear the horizon. Static.
The Sun finally lifts clear of the horizon.... HUGE amounts of static.
Up until this final point the Sun has really been below the horizon but its light has been refracted by the atmosphere. Now the Sun is truly above the horizon and so its radio static can reach your receiver.
Now go and make yourself a nice cup of tea, warm up and reflect on what you have learned.
Enjoy your physics.
In a word yes. The closer to the horizon the greater the refraction.
Sailors taking star readings on sextants will not trust a reading below 45 degrees above the horizon.
Watching a sunset. When the bottom of the sun is touching the horizon as you see it.
It's already below the horizon but refraction is bending the light round the surface of the earth.
Light is refracted when traveling through air, water, or glass.
If you see the sun just barely touching the horizon, it is actually just below the horizon. Atmospheric refraction causes this, bending the light by half a degree-the width of the sun's apparent diameter.
The biggest effect of the refraction occurs near the horizon. If you were to watch the sunset, when it appears that the sun is just touching the horizon that is when it is actually just dropped below the horizon. Light from the sun is bent slightly around the curve of the Earth. This means that you see the sun when it is slightly below the horizon.