The most important times extracted from the tracking station timeline for today’s AOS: acquisition of signal. The usual disclaimer: All times subject to change! Today, CET = UTC +1 hour

UTC Event
10:00 WAKE UP (2:00 am PST)
14:35 NASA DSS-14 (Goldstone 70m) BOT (Begin of track) – watching for signal just in case
~17:00 Rosetta turns on S-band transmitter (45 min OWLT – one-way light time for signal to reach Earth)
After 17:30 – from this time on all Rosetta times estimated
~17:45 NASA DSS-14 captures carrier signal
~18:10 Uplink command to ROSETTA to turn on telemetry (i.e. start downloading data)
18:15 DSS-43 (Canberra 70m) BOT
~18:55 Rosetta turns on telemetry
~19:40 First telemetry data captured at DSS-14 and DSS-43
20:34 ESA DSA1 (New Norcia 35m) BOT
21:45 Turn off DSS-14 uplink transmitter
21:50 Turn on DSS-43 uplink transmitter
21:50 DSS-14 End of Track (EOT)

PS: Quick answer to @Chris_Bloke from ESA’s Daniel Firre, one of our tracking station experts.

From spacecraft to ground (and vice versa) we rely on space communication standard for packet telemetry and telecommand on top of CCSDS channel coding standard. For moving data around between the ground stations and the control center here in Darmstadt, we use CCSDS Space Link Extension standard implemented on TCP-IP.