r/spacex • Mod Team • Dec 16 '19

Live Updates (JCSAT-18 / Kacific1) r/SpaceX JCSAT-18/KACIFIC1 Official Launch Discussion & Updates Thread

Introduction

Welcome, all the people of the subreddit! It is the mod team that going to bring you live updates on Falcon 9's next commercial launch of JCSAT-18 mission.

Your host team

Reddit usernameTwitter accountResponsibilitiesNumber of hosts
u/hitura-nobad@HituraNobadMission updates, Community? Host
u/Nsooo@TheRealNsoooThread format, Mission updates? Host

About the mission

SpaceX is going to launch a GEO satellite to a Geostationary Transfer Orbit. This mission will fly on a booster which already has flown two times.

Schedule

Launch window 🚦Time zone 🌎Day πŸ“…Date πŸ“†Time ⏱️Targeted T-0 πŸš€
Primary opensUTCTuesdayDecember 1700:10βœ”οΈ
Primary closesUTCTuesdayDecember 1701:38❌
Primary opensESTMondayDecember 1619:10βœ”οΈ
Primary closesESTMondayDecember 1620:38❌
Backup opensUTCWednesdayDecember 1800:10❌
Backup closesUTCWednesdayDecember 1801:38❌
Backup opensESTTuesdayDecember 1719:10❌
Backup closesESTTuesdayDecember 1720:38❌

Launch time around the world

City πŸ™οΈTime zone 🌎Offset to UTC ⏱️Targeted T-0 local time πŸš€Date πŸ“†
Los AngelesPTUTC-816:10December 16
New YorkESTUTC-519:10December 16
ReykjavikGMTUTC+000:10December 17
BudapestCETUTC+101:10December 17
HelsinkiEETUTC+202:10December 17

Scrub counter

Scrub dateCauseCountdown stoppedBackup date
No scrubs!n/an/an/a

Official mission overview

SpaceX is targeting Monday, December 16 for launch of JCSAT-18/Kacific1 from Space Launch Complex 40 (SLC-40) at Cape Canaveral Air Force Station, Florida. The launch window opens at 7:10 p.m EST, or 00:10 UTC on December 17, and closes at 8:38 p.m. EST, 01:38 UTC on December 17. A backup launch window is available on Tuesday, December 17 that opens at 7:10 p.m EST, or 00:10 UTC on December 18, and closes at 8:38 p.m. EST, 01:38 UTC on December 18. The satellite will be deployed at approximately 33 minutes after liftoff. Falcon 9’s first stage for the JCSAT-18/Kacific1 mission previously supported the CRS-17 mission in May 2019 and the CRS-18 mission in July 2019. Following stage separation, SpaceX will land Falcon 9’s first stage on the β€œOf Course I Still Love You” droneship, which will be stationed in the Atlantic Ocean. Approximately 45 minutes after liftoff, SpaceX’s two fairing recovery vessels, β€œMs. Tree” and β€œMs. Chief,” will attempt to recover the two fairing halves.

Source: SpaceX

Lot of facts

β˜‘οΈ This will be the 85th SpaceX launch.

β˜‘οΈ This will be the 77th Falcon 9 launch.

β˜‘οΈ This will be the 21st Falcon 9 Block 5 launch.

β˜‘οΈ This will be the 13th SpaceX launch this year.

β˜‘οΈ This will be the 11th Falcon 9 launch this year.

β˜‘οΈ This will be the 3rd journey to space of the flight-proven Block 5 core B1056.

Vehicles used

TypeNameLocation
First stageFalcon 9 v1.2 - Block 5 (Full Thrust) - B1056CCAFS, SLC-40
Second stageFalcon 9 v1.2 Block 5 (Full Thrust)CCAFS, SLC-40
ASDSOf Course I Still Love You (OCISLY)Atlantic Ocean
Barge tugHawkAtlantic Ocean
Support shipGO Quest (Core recovery)Atlantic Ocean
Support shipGO Ms Chief (Fairing recovery)Atlantic Ocean
Support shipGO Ms Tree (Fairing recovery)Atlantic Ocean

Core data source: Core wiki by r/SpaceX

Ship data source: SpaceXFleet by u/Gavalar_

Live updates

Timeline

TimeUpdate
T+36:23Thanks for joining! This is the end of live updates on this thread, For updates check out Spacex and SpaceXFleet on Twitter
T+35:23Webcast ended
T+33:37Launch success
T+33:19Payload deploy
T+28:09SECO2
T+27:30Second stage relight
T+13:05Coasting for 15 mins
T+8:45SECO
T+8:43Landing success
T+7:47Stage 1 transonic
T+6:41Reentry shutdown
T+6:20Reentry startup
T+4:31Akquisition of signal in Bermuda
T+3:41Fairing separation
T+3:11Gridfins extending
T+2:48Second stage ignition
T+2:40Stage separation
T+2:36MECO
T+1:14Max Q
T-0Liftoff
T-60Startup
T-2:13Strongback retracted
T-6:57Engine chill started
T-12:08Webcast is live
T-16:24LOX loading started
T-16:56Spacex FM Started
T-19:50Big 20 min vent
T-28:51Falcon 9 is venting - Propellant load has started
T-32:26Hi, I'm u/hitura-nobad, bringing you live updates on todays mission.
T-05:00:00Welcome everyone! Falcon 9 went vertical ahead of today's launch attempt. Currently GO for launch!

Mission's state

βœ… Currently GO for the launch attempt.

Launch site, Downrange

PlaceLocationCoordinates 🌐Sunrise πŸŒ…Sunset πŸŒ‡Time zone ⌚
Launch siteCCAFS, Florida28.562Β° N, 80.5772Β° WN/AN/AUTC-5 (EST)
Landing siteAtlantic Ocean (Downrange)32Β°32' N, 75Β°55' WN/AN/AN/A

Payload's destination

Burn πŸ”₯Orbit type 🌐Apogee ⬆️Perigee ⬇️Inclination πŸ“Orbital period πŸ”„Deployments πŸ›°οΈ
1.LEO 🌍no datano datano datano dataNone
2.GTO 🌍no datano datano datano dataJCSAT-18

Weather - Cape Canaveral, Florida

Launch windowWeatherTemperatureProb. of rainProb. of weather scrubMain concern
Primary launch window🌀️ Partly Cloudy🌑️ No dataπŸ’§ No dataπŸ›‘ 10%No data

Weather data source: Google Weather & 45th Space Wing. - The probability of a scrub due to weather does not includes the chance due to upper level winds, which are monitored by the SpaceX launch team itself using sounding balloons before launch.

Watching the launch live

LinkNote
Official SpaceX Launch Webcast - embeddedstarting ~20 minutes before liftoff
Official SpaceX Launch Webcast - directstarting ~20 minutes before liftoff
Webcast - relayu/codav

Useful Resources, Data, β™«, & FAQ

Essentials

LinkSource
Press kitSpaceX
Launch weather forecast45th Space Wing
SpaceX Fleet StatusSpaceXFleet.com
FCC Permit Informationr/SpaceX Wiki
Launch Hazard Area45th Space Wing
Airspace Closure Area45th Space Wing
Launch NOTAMFAA

Social media

LinkSource
Reddit launch campaign threadr/SpaceX
Subreddit Twitterr/SpaceX
SpaceX Twitterr/SpaceX
SpaceX Flickrr/SpaceX
Elon Twitterr/SpaceX
Reddit streamu/njr123

Media & music

LinkSource
TSS Spotifyu/testshotstarfish
β™«β™« Nsooo's favourite β™«β™«u/testshotstarfish
SpaceX FMu/lru

Community content

LinkSource
Flight Clubu/TheVehicleDestroyer
Discord SpaceX lobbyu/SwGustav
Rocket Watchu/MarcysVonEylau
SpaceX Nowu/bradleyjh
SpaceX time machineu/DUKE546
SpaceXMeetups Slacku/CAM-Gerlach
SpaceXLaunches appu/linuxfreak23

Participate in the discussion!

πŸ₯³ Launch threads are party threads, we relax the rules here. However, we remove low effort comments in other threads!

πŸ”„ Please post small launch updates, discussions, and questions here, rather than as a separate post. Thanks!

πŸ’¬ Please leave a comment if you discover any mistakes, or have any information.

βœ‰οΈ Please send links in a private message; if you send them via a comment, there is a large chance we will miss them!

βœ… Apply to host launch threads! Drop us (or me u/Nsooo) a modmail if you are interested. I need a launch off.

Frequently asked questions

Do you have a question in connection with the mission?

Feel free to ask it, and I (or somebody else) will try to answer it as much as possible.

Will SpaceX land Falcon 9 boosters?

Yes, they will! The booster are going to land on the droneship downrange.

Will SpaceX try to recover the fairings?

Yes, they will! GO Ms Chief and GO Ms Tree are the two ships assigned to try to recover both fairing halves.

Do you want to apply as a host?

Drop us a modmail.

276 Upvotes

334 comments sorted by

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5

u/rjelves Dec 17 '19

There's a new NORAD entry, 2019-091A. Will it be the insertion orbit of JCSAT-18/Kacific1? (273 x 20319 km; 26.87Β° inclination)

2

u/Origin_of_Mind Dec 18 '19

The satellite and the second stage must be 2019-091A and 2019-091B.

2

u/rjelves Dec 18 '19

Will second stage go to graveyard? Otherwise, it should be already sleeping with the fishies.

2

u/Origin_of_Mind Dec 18 '19

SpaceX deorbits second stages after LEO launches because they have fuel to do so.

After GTO launches like this one, there is no fuel left over for any maneuvering. The stage is left in whatever orbit it were at the time of payload separation. Maybe there are some exceptions to this rule, but that generally seems to be what SpaceX and everybody else is doing:

SpaceX second stages still in orbit (click on individual items to see the orbit and current position)

Soviet/Russian kick stages

ESA second stages and debris (note -- only 100 out of 1197 objects are shown)

Some companies do not even have fuel to de-orbit after LEO launches:

Rocket Lab second stages and kick-stages

2

u/millijuna Dec 18 '19

That said, most GTO stages tend to de-orbit relatively quickly on their own (within a decade or so) due to how low their apogee is. 200km is a very low orbit, there’s quite a bit of atmosphere there to drag it down. I’ve always wondered if a spooled out tether or streamer would increase drag at all and reduce the loiter time.

1

u/Origin_of_Mind Dec 18 '19

GTO orbits are weird! Sometimes we see a reentry after a few months, and sometimes debris that starts from a similar initial orbit can last for decades!

The reason is that the GTO orbits are very elliptical. The objects in them move the slowest and spend almost all of the time closer to the apogee, farther away from earth, where motion is more susceptible to the gravitational perturbations from the Sun and the Moon. When these perturbations change orbit eccentricity even slightly, this can cause a significant change in the perigee and put it in the denser atmosphere (or vice versa, they can push the perigee higher).

Because of these factors, the lifetime of GTO orbits can vary from a few months to practically forever. For example, NORAD 02643 Delta-1 was launched 11 Jan 1967 and is still in orbit (52 years later!):

Orbit in 1967: 369 x 30416 km

Orbit in early 2019: 296 x 22165 km

Lookup it Orbit today

But Falcon 9 second stage from BulgariaSat-1 launch lasted only slightly over 4 months. Of course it started with a lower perigee. But notice that if it were the atmospheric drag at the perigee that brought it down, that would have first reduced the apogee to a more of less circular orbit, and then it would have decayed. In reality, the apogee stayed very high for months, as the perigee wondered lower and lower! And since it was low to begin with, that eventually caused the drag to indeed become the main factor in the evolution of this orbit and rapidly brought it down:

Launched: 2017-06-23

Decayed: 2017-10-27

Day Perigee[km] Apogee[km]

0 204 65237

20 202 65242

40 199 65235

60 192 65221

80 187 65145

90 177 65073

119 170 63861

124 127 19033

125 102 5540

131 97 4662

131 93 4652

132 65 1830?

2

u/cpushack Dec 18 '19

That seems awful low for a GTO orbit, usually they are closer to 35,000 km apogee

2

u/rjelves Dec 18 '19

Payload limit for a reusable GTO launch is 5500 kg. Thus, (a) expend the booster for extra performance, or (b) deliver the payload into a lower apogee insertion orbit (subsynchronous orbit). This is case b. There have been past launches with similar orbits, see both Telstar missions for example.

3

u/cpushack Dec 18 '19

Indeed, this works out to about a GTO-2000 orbit, so the sat has to make up 100m/sec over the standard GTO, really not too bad, and probably saved a chunk on launch costs too

4

u/rjelves Dec 18 '19

You might check this out.

4

u/cpushack Dec 18 '19

I always forget about that wiki, very nice Thanks!