SpaceX F9 : Nusantara Satu (PSN VI)/GTO-1/SpaceIL : Feb. 21/22, 2019: Discussion

[punder]

GREAT headline from Eric Berger: "A lunar lander launches from Florida for the first time since Apollo 17"

https://arstechnica.com/science/2019/02/a-lunar-lander-launches-from-florida-for-the-first-time-since-apollo-17/

[gongora]

Perhaps we should have separate post launch mission threads for each payload?

Someone already started a SpaceIL thread:
https://forum.nasaspaceflight.com/index.php?topic=47217.0

[Firestorm76]

-FOR IMMEDIATE RELEASE-
Media contact: Zach Wallens, Puder PR, New York
[email protected]

WORLD’S FIRST PRIVATELY FUNDED LUNAR SPACECRAFT LAUNCHES SUCCESSFULLY ABOARD SPACEX ROCKET

...
The spacecraft successfully disengaged from the SpaceX Falcon 9 at around 60,000 kilometers above Earth’s surface...

Anyone want to let Mr. Wallens know that his fact is wrong about the separation being 60k kilometers altitude?  I believe the webcast showed that happening around 600 km.   We all know SpaceX rocks but a F9 cannot deliver payloads to at or above GEO (as this number indicates), directly!

[Comga]

-FOR IMMEDIATE RELEASE-
Media contact: Zach Wallens, Puder PR, New York
[email protected]

WORLD’S FIRST PRIVATELY FUNDED LUNAR SPACECRAFT LAUNCHES SUCCESSFULLY ABOARD SPACEX ROCKET

...
The spacecraft successfully disengaged from the SpaceX Falcon 9 at around 60,000 kilometers above Earth’s surface...

Anyone want to let Mr. Wallens know that his fact is wrong about the separation being 60k kilometers altitude?  I believe the webcast showed that happening around 600 km.   We all know SpaceX rocks but a F9 cannot deliver payloads to at or above GEO (as this number indicates), directly!

https://goo.gl/images/ftQ4Hk
Don't sweat the petty stuff. (And don't pet the sweaty stuff!)

[mn]

I'm trying to understand the reasons for waiting for S/C deployment after SECO 2.

At that point you are just floating freely, so why does it make a difference when you deploy? why do they wait x minutes after SECO 2 before deploying one payload and then another varying number of minutes before the next payload?

[lonestriker]

I'm trying to understand the reasons for waiting for S/C deployment after SECO 2.

At that point you are just floating freely, so why does it make a difference when you deploy? why do they wait x minutes after SECO 2 before deploying one payload and then another varying number of minutes before the next payload?

Likely due to making sure spacecraft separation distances are greater than minimal limits.  When they release a spacecraft, the pusher increases the released spacecraft velocity slightly and reduces the S2+remaining spacecraft velocity (equal and opposite reaction).  They wait until there's a certain distance/time and release their next spacecraft so they're not too close to each other.

[mn]

I'm trying to understand the reasons for waiting for S/C deployment after SECO 2.

At that point you are just floating freely, so why does it make a difference when you deploy? why do they wait x minutes after SECO 2 before deploying one payload and then another varying number of minutes before the next payload?

Likely due to making sure spacecraft separation distances are greater than minimal limits.  When they release a spacecraft, the pusher increases the released spacecraft velocity slightly and reduces the S2+remaining spacecraft velocity (equal and opposite reaction).  They wait until there's a certain distance/time and release their next spacecraft so they're not too close to each other.

A: That doesn't explain the wait before deploying the first (often the only) payload.

Edit: that wait was just over a minute so not really a 'wait'.

B: Iridium waited 100 seconds between deployments, here they waited over 10 minutes. I just can't imagine that's the reason.

[king1999]

NASA Administrator Jim Bridenstine comments in this press release doesn't even mentioned SpaceX...SAD!. 

Maybe no mention because  SpaceX was just the ride? In that case, it's progress? But who knows .

Yeah I noticed that too. A typical press release would mention the launcher by a few words (like "launched by a SpaceX Falcon 9 rocket"). There may be something going on with NASA reviewing "SpaceX culture" and AF reviewing "SpaceX certification process".

[lonestriker]

I'm trying to understand the reasons for waiting for S/C deployment after SECO 2.

At that point you are just floating freely, so why does it make a difference when you deploy? why do they wait x minutes after SECO 2 before deploying one payload and then another varying number of minutes before the next payload?

Likely due to making sure spacecraft separation distances are greater than minimal limits.  When they release a spacecraft, the pusher increases the released spacecraft velocity slightly and reduces the S2+remaining spacecraft velocity (equal and opposite reaction).  They wait until there's a certain distance/time and release their next spacecraft so they're not too close to each other.

A: That doesn't explain the wait before deploying the first (often the only) payload.

Edit: that wait was just over a minute so not really a 'wait'.

B: Iridium waited 100 seconds between deployments, here they waited over 10 minutes. I just can't imagine that's the reason.

Every webcast I've watched they've delayed deployment of the satellite, instead of immediate release.  The easiest explanation I can think of (just an educated guess) is to ensure proper orbit insertion.  If they need to relight S2 again to or use RCS to make minor adjustments, having the spacecraft attached to its ride is useful.  As for why they wait 10 minutes instead of 5, or some other random number?  Not sure on that one.  The major factors that change over time are the velocity of the spacecraft+S2 in their orbit (if elliptical), light/thermal changes with the sun, and tracking/overflight of earth tracking stations.

[ZachS09]

When the first GPS-III satellite launched last December, the satellite was deployed 47 minutes after SECO-2.

IIRC, the reason why is because the U.S. Air Force wanted ground coverage at the time of deployment.

https://forum.nasaspaceflight.com/index.php?topic=30912.msg1891709#msg1891709

[Stan-1967]

SpaceX, per their users guide, is also contractually bound to confirm payload separation, provide an orbit injection report that include ephemeris, payload environment, & any significant events or anomalies.   This would add some time after SECO to gather the data & make sure contractual obligations are met before the payload is released. ( hi Zuma..!) 

[johng]

Perhaps this is too late, but I have an observation of the launch that raises a question. 

I was viewing from the foot of the Garden Street Bridge (Max Brewer) in Titusville.  A few minutes into the launch myself and a few others observed a faintly green glowing object that appeared to be in fast fall/ freefall over the Cape.  The green glow and faint illumination reminded me of the thrusters on the Falcon 9 booster. 

Anyone know what that might have been?  The only thing I can think is that it was fairing related...

[DigitalMan]

Perhaps this is too late, but I have an observation of the launch that raises a question. 

I was viewing from the foot of the Garden Street Bridge (Max Brewer) in Titusville.  A few minutes into the launch myself and a few others observed a faintly green glowing object that appeared to be in fast fall/ freefall over the Cape.  The green glow and faint illumination reminded me of the thrusters on the Falcon 9 booster. 

Anyone know what that might have been?  The only thing I can think is that it was fairing related...

I was watching the launch with my binoculars, it looked clean the whole way.

[Prettz]

https://twitter.com/spacecoast_stve/status/1100433099685576704

#Falcon9 has been placed on the transporter. Unfortunately, I showed up too late for it to be included in my time lapse, but here’s a shot for y’all to see. @SpaceXFleet

I'm sorry... they're still removing the legs? Man oh man, what happened with that whole redesign?

[Kenp51d]

IIRC this boosters next flight is Dragon  abort test (flight#4). It is unlikely to survive the abort. So it makes great sense ($$$$ literally) to remove a la dinghy related hardware.

Ken

Sent from my SM-T590 using Tapatalk

[whitelancer64]

Perhaps this is too late, but I have an observation of the launch that raises a question. 

I was viewing from the foot of the Garden Street Bridge (Max Brewer) in Titusville.  A few minutes into the launch myself and a few others observed a faintly green glowing object that appeared to be in fast fall/ freefall over the Cape.  The green glow and faint illumination reminded me of the thrusters on the Falcon 9 booster. 

Anyone know what that might have been?  The only thing I can think is that it was fairing related...

How long did you see it? Was it flashing? It may have been a drone filming the launch if so. Or it could have been anything from a meteorite far off in the distance to a nearby firefly.

[ZachS09]

https://twitter.com/spacecoast_stve/status/1100433099685576704

#Falcon9 has been placed on the transporter. Unfortunately, I showed up too late for it to be included in my time lapse, but here’s a shot for y’all to see. @SpaceXFleet

I'm sorry... they're still removing the legs? Man oh man, what happened with that whole redesign?

I don’t know. Maybe they decided not to fold the legs back up after a few tests with certain boosters.

[teetlebomb]

Perhaps this is too late, but I have an observation of the launch that raises a question. 

I was viewing from the foot of the Garden Street Bridge (Max Brewer) in Titusville.  A few minutes into the launch myself and a few others observed a faintly green glowing object that appeared to be in fast fall/ freefall over the Cape.  The green glow and faint illumination reminded me of the thrusters on the Falcon 9 booster. 

Anyone know what that might have been?  The only thing I can think is that it was fairing related...

How long did you see it? Was it flashing? It may have been a drone filming the launch if so. Or it could have been anything from a meteorite far off in the distance to a nearby firefly.

I was in Titusville with my family for the launch. After MECO we got some [bad] video of the entry burn, as the moon started to rise. But that is obviously about six minutes after the launch.

[ulm_atms]

Perhaps this is too late, but I have an observation of the launch that raises a question. 

I was viewing from the foot of the Garden Street Bridge (Max Brewer) in Titusville.  A few minutes into the launch myself and a few others observed a faintly green glowing object that appeared to be in fast fall/ freefall over the Cape.  The green glow and faint illumination reminded me of the thrusters on the Falcon 9 booster. 

Anyone know what that might have been?  The only thing I can think is that it was fairing related...

Only two things "should" be falling off the rocket at that time.  The fairing and the stiffing ring for the 2nd stage nozzle.  Anyone think that ring could be it?  It should be going fast enough to vaporize when entering the atmosphere....pure shot in the dark here though....

[Jarnis]

I'm sorry... they're still removing the legs? Man oh man, what happened with that whole redesign?

The next flight of this booster will have no legs (in-flight abort) so taking them off makes sense. This case is no indication of if they could have folded them.