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The US chose Ariane 5 to launch the James Webb Telescope, says it all, don't you think? ;)

fransje26 3y ago
And the orbit injection was so precise that they greatly increased the theoretical lifetime of the mission, from an expected minimum of 5 years to well beyond 10 years.
panick21_ 3y ago
No it doesn't. Why do people keep repeating this? That not how anything works. The US 'chose' Ariane 5 because guess what, ESA paid for the launch. Yes ESA contribution to the James Webb project was partly the launch. And if you pay for it you get to select the rocket. And because its ESA, they selected Ariane 5. Had ESA not paid for it, an Atlas or a Delta vehicle had all the necessary NASA certifications to launch a payload of that class.
- WhereIsTheTruth 3y ago
  Lies "We chose Ariane in the early 2000's for a combination of reliability (it was the only launch vehicle that met NASA's requirements for launching a mission like Webb) and for the value it brought via our international partnership." https://jwst.nasa.gov/content/about/faqs/faq.html#whyAriane5 https://jwst.nasa.gov/content/about/faqs/faq.html#whyAriane5
  - signatoremo 3y ago
    “it was the only launch vehicle that met NASA's requirements for launching a mission like Webb” The key word is “was”. Atlas V, Delta IV and Falcon Heavy would all have been suitable for the job. They just didn’t exist or just debut at the time NASA went with Ariane 5. Keep in mind JWST was supposed to launch early in 2010s, not a decade later. A big selling point for Ariane 5 is in the part that you left out: European Space Agency provided us a launch vehicle and associated services on a no exchange of funds basis. In exchange, NASA guaranteed European scientists a fraction of observing time on Webb (roughly 15%). Since architectural realities of Webb and international technology restrictions (plus industrial capabilities and strategic technology interests) meant we couldn't have a spacecraft bus or a sunshield or telescope parts from Europe, we asked for the launch vehicle, launch services and science instruments instead. Basically NASA got a launch vehicle without any money exchanged (as opposed to paying probably a billion dollar to ULA). This was crucial given the cost overrun of the program. Also NASA couldn’t use Europe’s technologies on the telescope itself for non-technical reasons, so a launch vehicle it was. Ariane 5 is an extremely reliable and capable vehicle, nobody can refute that.

And the orbit injection was so precise that they greatly increased the theoretical lifetime of the mission, from an expected minimum of 5 years to well beyond 10 years.

panick21_ 3y ago

No it doesn't. Why do people keep repeating this? That not how anything works. The US 'chose' Ariane 5 because guess what, ESA paid for the launch. Yes ESA contribution to the James Webb project was partly the launch. And if you pay for it you get to select the rocket. And because its ESA, they selected Ariane 5. Had ESA not paid for it, an Atlas or a Delta vehicle had all the necessary NASA certifications to launch a payload of that class.

WhereIsTheTruth 3y ago
Lies "We chose Ariane in the early 2000's for a combination of reliability (it was the only launch vehicle that met NASA's requirements for launching a mission like Webb) and for the value it brought via our international partnership." https://jwst.nasa.gov/content/about/faqs/faq.html#whyAriane5 https://jwst.nasa.gov/content/about/faqs/faq.html#whyAriane5
- signatoremo 3y ago
  “it was the only launch vehicle that met NASA's requirements for launching a mission like Webb” The key word is “was”. Atlas V, Delta IV and Falcon Heavy would all have been suitable for the job. They just didn’t exist or just debut at the time NASA went with Ariane 5. Keep in mind JWST was supposed to launch early in 2010s, not a decade later. A big selling point for Ariane 5 is in the part that you left out: European Space Agency provided us a launch vehicle and associated services on a no exchange of funds basis. In exchange, NASA guaranteed European scientists a fraction of observing time on Webb (roughly 15%). Since architectural realities of Webb and international technology restrictions (plus industrial capabilities and strategic technology interests) meant we couldn't have a spacecraft bus or a sunshield or telescope parts from Europe, we asked for the launch vehicle, launch services and science instruments instead. Basically NASA got a launch vehicle without any money exchanged (as opposed to paying probably a billion dollar to ULA). This was crucial given the cost overrun of the program. Also NASA couldn’t use Europe’s technologies on the telescope itself for non-technical reasons, so a launch vehicle it was. Ariane 5 is an extremely reliable and capable vehicle, nobody can refute that.