Time dilation field probe
From The Stargate Omnipedia
Probe designed by the Atlantis expedition to enter and study a gas giant. The unit is divided into two portions, connected by a long, sturdy tether. While one end of the device enters the giant, the other end remains outside to record (or relay) data.
KEY EPISODE
Epiphany - At Zelenka's suggestion, Weir's Puddle Jumper attempts to launch their atmospheric probe into the time dilation field of the Cloister planet, but the unit is destroyed upon impact with the field.