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Emily Lakdawalla • Jun 16, 2016
Timeline of Juno Jupiter Orbit Insertion events
Today NASA held a press briefing and released a press kit for the impending orbit insertion of the Juno spacecraft. The 35-minute orbit insertion burn is scheduled to begin July 5 at 03:18 UTC (July 4 20:18, PDT). Juno gets one chance at a successful orbit insertion; if it overshoots Jupiter, it goes into an inclined solar orbit that likely won't ever return to the giant planet. At the briefing today, project manager Rick Nybakken said that it would take at least 20 minutes of rocket firing for Juno to enter orbit successfully, and 30 minutes for it to enter a good science orbit. If something happens during orbit insertion, the spacecraft has an auto-restart capability that will allow it to try to recover from an anomaly and continue firing the rocket within 500 seconds.
Following is a timeline of orbit-insertion-related events that I cobbled together from the JPL media schedule and the press kit. All times are Earth Received Time; the actual events unfold 48 minutes earlier than these times, according to the spacecraft clock. A live broadcast will take place on NASA TV during orbit insertion. I'll be reporting live (mostly on Twitter) from the Jet Propulsion Laboratory. Go Juno!
| Event | Time (PDT) | Time (EDT) | Time (UTC) |
|---|---|---|---|
| Open main engine cover; main engine auto-restart enabled | 20 Jun | 20 Jun | 20 Jun |
| Open main engine propellant valves | 27 Jun | 27 Jun | 27 Jun |
| Pressurize propulsion system | 28 Jun | 28 Jun | 28 Jun |
| Science instruments turned off | 29 Jun | 29 Jun | 29 Jun |
| Spacecraft computer begins running orbit insertion command sequence | 30 Jun | 30 Jun | 30 Jun |
| Mission overview news briefing | 30 Jun 10:00 | 30 Jun 13:00 | 30 Jun 17:00 |
| Mission outreach briefing | 30 Jun 11:00 | 30 Jun 14:00 | 30 Jun 18:00 |
| Pre-orbit-insertion briefing | 4 Jul 09:00 | 4 Jul 12:00 | 4 Jul 16:00 |
| Begin transmitting tones; switch telecom to medium gain antenna | 4 Jul 18:13 | 4 Jul 21:13 | 5 Jul 01:13 |
| Begin slow, first turn of 15 degrees away from the Sun, toward orbit insertion attitude | 4 Jul 18:16 | 4 Jul 21:16 | 5 Jul 01:16 |
| Begin fast, large turn to orbit insertion attitude | 4 Jul 19:28 | 4 Jul 22:28 | 5 Jul 02:28 |
| NASA TV broadcast begins | 4 Jul 19:30 | 4 Jul 22:30 | 5 Jul 02:30 |
| Switch to toroidal low gain antenna | 4 Jul 19:41 | 4 Jul 22:41 | 5 Jul 02:41 |
| Begin nutation damping activity to remove remaining wobble | 4 Jul 19:45 | 4 Jul 22:45 | 5 Jul 02:45 |
| Begin fine-tune adjustment of the orbit insertion attitude | 4 Jul 19:50 | 4 Jul 22:50 | 5 Jul 02:50 |
| Begin approx. 5-minute spin-up from 2 to 5 rotations per minute | 4 Jul 19:56 | 4 Jul 22:56 | 5 Jul 02:56 |
| Jupiter orbit insertion burn begins | 4 Jul 20:18 | 4 Jul 23:18 | 5 Jul 03:18 |
| Start 35-minute main engine burn | 4 Jul 20:18 | 4 Jul 23:18 | 5 Jul 03:18 |
| Capture into Jupiter orbit achieved | 4 Jul 20:38 | 4 Jul 23:38 | 5 Jul 03:38 |
| Jupiter orbit insertion burn ends | 4 Jul 20:53 | 4 Jul 23:53 | 5 Jul 03:53 |
| Close propulsion pressurant valves, ending burn | 4 Jul 20:53 | 4 Jul 23:53 | 5 Jul 03:53 |
| Begin approx. 5-minute spin-down from 5 to 2 rotations per minute | 4 Jul 20:55 | 4 Jul 23:55 | 5 Jul 03:55 |
| Begin turn to sun-pointed attitude | 4 Jul 21:07 | 5 Jul 00:07 | 5 Jul 04:07 |
| Switch telecom to medium gain antenna | 4 Jul 21:11 | 5 Jul 00:11 | 5 Jul 04:11 |
| Begin transmitting telemetry (it could take 20 minutes or more to lock onto telemetry signal) | 4 Jul 21:16 | 5 Jul 00:16 | 5 Jul 04:16 |
| Post-orbit-insertion briefing | 4 Jul 22:00 | 5 Jul 01:00 | 5 Jul 05:00 |
| Capture Orbit Phase begins | 4 Jul 22:48 | 5 Jul 01:48 | 5 Jul 05:48 |
There will be no images taken during orbit insertion, because all of the instruments will be turned off. Read my JunoCam explainer for more about that.
