On January 11 2022 01:19 Lmui wrote: Some really good news about Webb.
Because of how good the performance from Ariane was, the lifespan of Webb before refueling is over 20 years. The odds of us having a good way to refuel it, or even outright replace it (Assuming starship or any other big rocket is available in 20 years) is a pretty good bet.
That's dope. If you can place it further into orbit and save it from burning as much fuel, then that fuel can be used to keep it alive longer. I didn't know a lot about the Ariane 5 but it's good that it overdelivered on launching the JWST. Waiting for summer to come to get any information is going to be harsh lol.
It's not just how much power it had, it's how precisely it delivered the power. The design of Webb meant that it could not, under any circumstance overshoot the L2 insertion. If it did, there is no way to turn Webb around and decelerate the vehicle. This meant Ariane needed to undershoot the L2 value, and have Webb's thrusters do the precision work. Ariane's engineers put the very best of the best into the vehicle, resulting in tighter error bounds for the vehicle than would otherwise be possible. That's paid off handsomely in getting it basically within spitting distance, so Webb had pretty much twice as much propellant as they were hoping for.
I wonder if the Ariane group had the same design philosophy (or most other space outfits for that matter) as SpaceX, where would they be at the moment? I know they do a lot of launches, but I haven't heard of their heavy lift vehicles or any other plans besides the 5. If they have precision like this, then I can only imagine if they took to making larger vehicles for more ambitious projects.
It's one thing that Falcon could not do as effectively. The Merlin vacuum has a minimum thrust of 360kN while the Ariane 5's second stage's maximum thrust is 62.2kN.
The acceleration rate is far slower with Ariane 5 compared to Falcon 9, so naively, falcon would be hard pressed to deliver it anywhere near as accurately.
The two organizations have different goals in the end though. SpaceX is private, so must either make money, or attract investment. Ariane is assured access to space for the European Union/France, and competition is a side effect. There's no market for an ultra-heavy lift vehicle, and no need to develop one yet. We know what SLS is like, and I doubt Ariane wants to touch that area. Ariane 6 is going to be interesting, because it's a culmination of nearly a decade of work alongside the emergence of SpaceX and cheap access to space.
On January 11 2022 01:19 Lmui wrote: Some really good news about Webb.
Because of how good the performance from Ariane was, the lifespan of Webb before refueling is over 20 years. The odds of us having a good way to refuel it, or even outright replace it (Assuming starship or any other big rocket is available in 20 years) is a pretty good bet.
That's dope. If you can place it further into orbit and save it from burning as much fuel, then that fuel can be used to keep it alive longer. I didn't know a lot about the Ariane 5 but it's good that it overdelivered on launching the JWST. Waiting for summer to come to get any information is going to be harsh lol.
It's not just how much power it had, it's how precisely it delivered the power. The design of Webb meant that it could not, under any circumstance overshoot the L2 insertion. If it did, there is no way to turn Webb around and decelerate the vehicle. This meant Ariane needed to undershoot the L2 value, and have Webb's thrusters do the precision work. Ariane's engineers put the very best of the best into the vehicle, resulting in tighter error bounds for the vehicle than would otherwise be possible. That's paid off handsomely in getting it basically within spitting distance, so Webb had pretty much twice as much propellant as they were hoping for.
I wonder if the Ariane group had the same design philosophy (or most other space outfits for that matter) as SpaceX, where would they be at the moment? I know they do a lot of launches, but I haven't heard of their heavy lift vehicles or any other plans besides the 5. If they have precision like this, then I can only imagine if they took to making larger vehicles for more ambitious projects.
It's one thing that Falcon could not do as effectively. The Merlin vacuum has a minimum thrust of 360kN while the Ariane 5's second stage's maximum thrust is 62.2kN.
The acceleration rate is far slower with Ariane 5 compared to Falcon 9, so naively, falcon would be hard pressed to deliver it anywhere near as accurately.
The two organizations have different goals in the end though. SpaceX is private, so must either make money, or attract investment. Ariane is assured access to space for the European Union/France, and competition is a side effect. There's no market for an ultra-heavy lift vehicle, and no need to develop one yet. We know what SLS is like, and I doubt Ariane wants to touch that area. Ariane 6 is going to be interesting, because it's a culmination of nearly a decade of work alongside the emergence of SpaceX and cheap access to space.
But isn't the thrust a matter of programming? As they've shown with Starship, they can toggle them on and off, use one engine if needed or use any combination. So couldn't SpaceX, with some engineering and programming ingenuity, accomplish something similar?
On January 11 2022 01:19 Lmui wrote: Some really good news about Webb.
Because of how good the performance from Ariane was, the lifespan of Webb before refueling is over 20 years. The odds of us having a good way to refuel it, or even outright replace it (Assuming starship or any other big rocket is available in 20 years) is a pretty good bet.
That's dope. If you can place it further into orbit and save it from burning as much fuel, then that fuel can be used to keep it alive longer. I didn't know a lot about the Ariane 5 but it's good that it overdelivered on launching the JWST. Waiting for summer to come to get any information is going to be harsh lol.
It's not just how much power it had, it's how precisely it delivered the power. The design of Webb meant that it could not, under any circumstance overshoot the L2 insertion. If it did, there is no way to turn Webb around and decelerate the vehicle. This meant Ariane needed to undershoot the L2 value, and have Webb's thrusters do the precision work. Ariane's engineers put the very best of the best into the vehicle, resulting in tighter error bounds for the vehicle than would otherwise be possible. That's paid off handsomely in getting it basically within spitting distance, so Webb had pretty much twice as much propellant as they were hoping for.
I wonder if the Ariane group had the same design philosophy (or most other space outfits for that matter) as SpaceX, where would they be at the moment? I know they do a lot of launches, but I haven't heard of their heavy lift vehicles or any other plans besides the 5. If they have precision like this, then I can only imagine if they took to making larger vehicles for more ambitious projects.
It's one thing that Falcon could not do as effectively. The Merlin vacuum has a minimum thrust of 360kN while the Ariane 5's second stage's maximum thrust is 62.2kN.
The acceleration rate is far slower with Ariane 5 compared to Falcon 9, so naively, falcon would be hard pressed to deliver it anywhere near as accurately.
The two organizations have different goals in the end though. SpaceX is private, so must either make money, or attract investment. Ariane is assured access to space for the European Union/France, and competition is a side effect. There's no market for an ultra-heavy lift vehicle, and no need to develop one yet. We know what SLS is like, and I doubt Ariane wants to touch that area. Ariane 6 is going to be interesting, because it's a culmination of nearly a decade of work alongside the emergence of SpaceX and cheap access to space.
But isn't the thrust a matter of programming? As they've shown with Starship, they can toggle them on and off, use one engine if needed or use any combination. So couldn't SpaceX, with some engineering and programming ingenuity, accomplish something similar?
No doubt Webb got the best efforts, but I don't believe Ariane 5 worked in a way much better than any of the competitors. Ariane 5 was chosen because it was the only one that fit the dimensions of Webb, even Falcon Heavy is a bit too thin.
On January 11 2022 01:19 Lmui wrote: Some really good news about Webb.
Because of how good the performance from Ariane was, the lifespan of Webb before refueling is over 20 years. The odds of us having a good way to refuel it, or even outright replace it (Assuming starship or any other big rocket is available in 20 years) is a pretty good bet.
That's dope. If you can place it further into orbit and save it from burning as much fuel, then that fuel can be used to keep it alive longer. I didn't know a lot about the Ariane 5 but it's good that it overdelivered on launching the JWST. Waiting for summer to come to get any information is going to be harsh lol.
It's not just how much power it had, it's how precisely it delivered the power. The design of Webb meant that it could not, under any circumstance overshoot the L2 insertion. If it did, there is no way to turn Webb around and decelerate the vehicle. This meant Ariane needed to undershoot the L2 value, and have Webb's thrusters do the precision work. Ariane's engineers put the very best of the best into the vehicle, resulting in tighter error bounds for the vehicle than would otherwise be possible. That's paid off handsomely in getting it basically within spitting distance, so Webb had pretty much twice as much propellant as they were hoping for.
I wonder if the Ariane group had the same design philosophy (or most other space outfits for that matter) as SpaceX, where would they be at the moment? I know they do a lot of launches, but I haven't heard of their heavy lift vehicles or any other plans besides the 5. If they have precision like this, then I can only imagine if they took to making larger vehicles for more ambitious projects.
It's one thing that Falcon could not do as effectively. The Merlin vacuum has a minimum thrust of 360kN while the Ariane 5's second stage's maximum thrust is 62.2kN.
The acceleration rate is far slower with Ariane 5 compared to Falcon 9, so naively, falcon would be hard pressed to deliver it anywhere near as accurately.
The two organizations have different goals in the end though. SpaceX is private, so must either make money, or attract investment. Ariane is assured access to space for the European Union/France, and competition is a side effect. There's no market for an ultra-heavy lift vehicle, and no need to develop one yet. We know what SLS is like, and I doubt Ariane wants to touch that area. Ariane 6 is going to be interesting, because it's a culmination of nearly a decade of work alongside the emergence of SpaceX and cheap access to space.
But isn't the thrust a matter of programming? As they've shown with Starship, they can toggle them on and off, use one engine if needed or use any combination. So couldn't SpaceX, with some engineering and programming ingenuity, accomplish something similar?
No doubt Webb got the best efforts, but I don't believe Ariane 5 worked in a way much better than any of the competitors. Ariane 5 was chosen because it was the only one that fit the dimensions of Webb, even Falcon Heavy is a bit too thin.
Thank you for the thread. Everyone but BO and Boeing it seems are good at getting their systems to orbit. And one would have to imagine, if Starship ever got out of regulatory hell, what they would be able to do with their system. That launch, in my opinion, is going to change everything.
On January 11 2022 01:19 Lmui wrote: Some really good news about Webb.
Because of how good the performance from Ariane was, the lifespan of Webb before refueling is over 20 years. The odds of us having a good way to refuel it, or even outright replace it (Assuming starship or any other big rocket is available in 20 years) is a pretty good bet.
That's dope. If you can place it further into orbit and save it from burning as much fuel, then that fuel can be used to keep it alive longer. I didn't know a lot about the Ariane 5 but it's good that it overdelivered on launching the JWST. Waiting for summer to come to get any information is going to be harsh lol.
It's not just how much power it had, it's how precisely it delivered the power. The design of Webb meant that it could not, under any circumstance overshoot the L2 insertion. If it did, there is no way to turn Webb around and decelerate the vehicle. This meant Ariane needed to undershoot the L2 value, and have Webb's thrusters do the precision work. Ariane's engineers put the very best of the best into the vehicle, resulting in tighter error bounds for the vehicle than would otherwise be possible. That's paid off handsomely in getting it basically within spitting distance, so Webb had pretty much twice as much propellant as they were hoping for.
I wonder if the Ariane group had the same design philosophy (or most other space outfits for that matter) as SpaceX, where would they be at the moment? I know they do a lot of launches, but I haven't heard of their heavy lift vehicles or any other plans besides the 5. If they have precision like this, then I can only imagine if they took to making larger vehicles for more ambitious projects.
It's one thing that Falcon could not do as effectively. The Merlin vacuum has a minimum thrust of 360kN while the Ariane 5's second stage's maximum thrust is 62.2kN.
The acceleration rate is far slower with Ariane 5 compared to Falcon 9, so naively, falcon would be hard pressed to deliver it anywhere near as accurately.
The two organizations have different goals in the end though. SpaceX is private, so must either make money, or attract investment. Ariane is assured access to space for the European Union/France, and competition is a side effect. There's no market for an ultra-heavy lift vehicle, and no need to develop one yet. We know what SLS is like, and I doubt Ariane wants to touch that area. Ariane 6 is going to be interesting, because it's a culmination of nearly a decade of work alongside the emergence of SpaceX and cheap access to space.
But isn't the thrust a matter of programming? As they've shown with Starship, they can toggle them on and off, use one engine if needed or use any combination. So couldn't SpaceX, with some engineering and programming ingenuity, accomplish something similar?
No doubt Webb got the best efforts, but I don't believe Ariane 5 worked in a way much better than any of the competitors. Ariane 5 was chosen because it was the only one that fit the dimensions of Webb, even Falcon Heavy is a bit too thin.
It really depends on exactly how precise other launchers are. Ariane 5 nailed every orbital parameter except semi-major axis, and that was barely off in favour of JWST (not sure about how much, but ballpark math puts it in the 1-2m/s of dV range (based on dv of hohmann transfer between lower/high semi-major axis). Not saying falcon couldn't have done that, but stopping within 1-2m/s is going to be easier with a lower thrust engine. For the other orbital parameters, I wouldn't be surprised if they could get within the same precision as Ariane, but the semi-major (velocity) is one that would be hard to match.
TAMPA, Fla. — SpaceX has dropped a plan to use Falcon 9 to launch the 30,000 satellites in its proposed second-generation Starlink broadband constellation, and is instead focusing on a configuration leveraging its upcoming Starship vehicle.
The decision follows development progress that SpaceX said exceeded the company’s expectations and means it could start “launching the Gen2 system as early as March 2022,” SpaceX lawyer William Wiltshire said in a Jan. 7 letter to the Federal Communications Commission.
Starship missions are subject to a favorable environmental review into SpaceX’s launch facility at Boca Chica, Texas, which the Federal Aviation Administration expects to complete Feb. 28.
SpaceX currently has FCC approval to deploy 4,408 satellites to low Earth orbit at an altitude of around 550 kilometers, and has launched more than half of them to date. The FCC has not yet approved SpaceX’s plans for the larger, second-generation constellation. SpaceX asked the FCC to expedite approval now that it has settled on the Starship-launched configuration.
“Just as terrestrial wireless networks meet customer demands by operating more than one generation of technology simultaneously, SpaceX plans to use both of its networks to provide superior service,” Wiltshire wrote.
“SpaceX will continue to maintain its first-generation system, launching replacement satellites as appropriate to sustain the orbits in which it operates, even as it conducts the initial deployment of the Gen2 system. To be clear, operating both systems simultaneously does not mean that SpaceX will necessarily operate all of the satellites under its authorizations at all times in all areas.”
He said a “SpaceX customer user terminal will be able to receive service from satellites of either system.”
In August, the company proposed two configurations for a follow-on network it originally submitted to the FCC in 2020, with both options designed to spread satellites more evenly across nine to 12 inclined orbits for denser and more consistent coverage — without needing additional spectrum or spacecraft.
The proposed Starship configuration, which SpaceX had earlier said was its preferred option, comprises 29,988 satellites at altitudes of between 340 and 614 kilometers across nine inclined orbits.
The now-abandoned Falcon 9 configuration would have spread 29,996 satellites across 12 orbital inclinations, at altitudes between 328 and 614 kilometers.
Amazon and other SpaceX rivals had called on the FCC to dismiss the amended plan, saying requesting permission for more than one configuration encourages speculative application behavior from future constellation operators.
TAMPA, Fla. — SpaceX has dropped a plan to use Falcon 9 to launch the 30,000 satellites in its proposed second-generation Starlink broadband constellation, and is instead focusing on a configuration leveraging its upcoming Starship vehicle.
The decision follows development progress that SpaceX said exceeded the company’s expectations and means it could start “launching the Gen2 system as early as March 2022,” SpaceX lawyer William Wiltshire said in a Jan. 7 letter to the Federal Communications Commission.
Starship missions are subject to a favorable environmental review into SpaceX’s launch facility at Boca Chica, Texas, which the Federal Aviation Administration expects to complete Feb. 28.
SpaceX currently has FCC approval to deploy 4,408 satellites to low Earth orbit at an altitude of around 550 kilometers, and has launched more than half of them to date. The FCC has not yet approved SpaceX’s plans for the larger, second-generation constellation. SpaceX asked the FCC to expedite approval now that it has settled on the Starship-launched configuration.
“Just as terrestrial wireless networks meet customer demands by operating more than one generation of technology simultaneously, SpaceX plans to use both of its networks to provide superior service,” Wiltshire wrote.
“SpaceX will continue to maintain its first-generation system, launching replacement satellites as appropriate to sustain the orbits in which it operates, even as it conducts the initial deployment of the Gen2 system. To be clear, operating both systems simultaneously does not mean that SpaceX will necessarily operate all of the satellites under its authorizations at all times in all areas.”
He said a “SpaceX customer user terminal will be able to receive service from satellites of either system.”
In August, the company proposed two configurations for a follow-on network it originally submitted to the FCC in 2020, with both options designed to spread satellites more evenly across nine to 12 inclined orbits for denser and more consistent coverage — without needing additional spectrum or spacecraft.
The proposed Starship configuration, which SpaceX had earlier said was its preferred option, comprises 29,988 satellites at altitudes of between 340 and 614 kilometers across nine inclined orbits.
The now-abandoned Falcon 9 configuration would have spread 29,996 satellites across 12 orbital inclinations, at altitudes between 328 and 614 kilometers.
Amazon and other SpaceX rivals had called on the FCC to dismiss the amended plan, saying requesting permission for more than one configuration encourages speculative application behavior from future constellation operators.
EPT
