How does NASA sends photos from outer space to Earth and how long do photos from Jupiter take to reach Earth?

Answer 1

The simple answer is, over a radio transmission containing the picture information and between 35 and 52 minutes depending on how far away we are from Jupiter at the time. NASA has employed many different techniques to send pictures back from spacecraft over their history. Some early lunar photos were actually taken with a film camera and robotically developed in the spacecraft while it orbited the moon. The photos where then moved in front of a special TV camera and sent back to earth over a radio transmission, much like how Television signals get to your TV. Eventually tube based cameras wee used to capture reasonably higher resolution photos almost like one still frame from a video camera. Most of the wonderful images from older missions to planets like Jupiter are actually many small photos assembled into one "high-resolution" mosaic. As digital cameras have improved over time they are now used in spacecraft to capture digital pictures and send the data back to earth as a computer file. The photos are taken and stored inside the spacecraft, on a digital tape as late as the 1990s and now on solid state storage, and sent back to earth over the data uplink. This is essentially a radio transmission that is sending computer information instead of a voice transmission or a TV picture, much like a compute modem connects over a telephone line. If you were to listen to it, it would sound like the white noise or the screeching, hissing noise computer modems make when dialing into to their internet provider. The uplinks are getting faster as technology increase and while you could say it's similar in ways to wireless data services like WiFi laptops or 3G cell phones, the connection speeds are still much slower. How long does the transmission take to reach earth? This depends on where Earth is in it's orbit and where Jupiter is in it's orbit. At times we are as close as 390,000,000 miles from Jupiter and at times we are as far away as 570,000,000 miles. This means transmissions from Jupiter take between 35 and 52 minutes to reach earth.