Good question!

We are glad we are launching at solar minimum because the structure in the solar wind is much simpler at solar minimum and we have a better chance of sorting things out!

Although the prime mission only extends to 2026, if the spacecraft and instruments are still operating ..and if NASA's budget permits ... the mission can be extended.

Paulett

From the point of energetic particles, we did want to launch into a more active period - but you go when NASA approves the mission and tells you you can go! We're going to learn a lot from Solar Probe no matter when it gets launched; and since this mission, in different forms, has been talked about and designed and pushed for more than 25 years it is thrilling that we finally have the technology to do it.

Generally for spacecraft missions, NASA only guarantees funding for the 'prime' mission, which is 7 years for Solar Probe. However, typically if the instruments and spacecraft are healthy and still obtaining useful data it is cheaper to keep operating them than it is to build another spacecraft. So, most of the NASA missions are well beyond their prime mission; for example, both the Advanced Composition Explorer and Wind spacecraft are more than 20 years old (and their prime missions were 3 years) and they are still going strong. So we're definitely hoping Solar Probe will continue to send us remarkable data well past its 7 year prime mission.

-Christina