spacemika

How does the New Horizons probe stay warm?

From reading specs, the probe is designed a bit like a thermos bottle to stay insulated and operate at room temperature, but what's the original heat source? Is it the same plutonium radiation that is used to power the probe?

Thank you!

What are some things that could go wrong during the qualification test? What would it look like?

Does the change from Mission to Mars to Return to the Moon impact the design or intended usage of SLS?

Is the drawn out SLS test schedule (over a year from last qualification test to this one; over a year from this month's qualification test to the test flight!) dictated by budget, technology, or a combination of both?

Related: Is SLS or Orion development setting the 2018 test flight? What happens if only one component is ready on time?