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Originally Posted by Bob Kontak

This morning it was moving away from earth at 1.0551 miles per second. That's slightly over 3,600MPH. What happened to the 17K MPH?

Also the spacecraft is slowing down. Now it's 0.93 miles per second at 5:00PM.

What gives with the "slow" speeds? I'm guessing way easier to slow down?

Apollo took a couple days to get to the Moon so they weren't going 17k MPH either. Correct?

Nope, the 17k mph is almost certainly correct. Also the speed moving away from the earth (including the deceleration) is probably correct.

Imagine that you've got a weight on the end of a 6' string , and you're holding the string and spinning the weight around above your head, maybe 36 feet per minute in a circle. Also imagine that there's a tree 8' away. If you start slowly letting more string out, say 1" of string every 5 seconds. That would mean that the weight on the end of the string was approaching the tree at 1 foot per minute, but the weight on the end of the string is spinning at 36 feet per minute.

That's how Webb is approaching at one speed, but going another. Also, as the distance from the earth increases, the circumference of the orbit also increases, which means that it takes longer to complete and orbit and therefore the orbits are getting larger at a slower rate.