"The SPHEREx mission <snip> will map the entire sky four times over two years, offering scientists a chance to study how galaxies form and evolve, and providing a window into how the universe came to be."<p>So each object will be scanned ~6 months from the previous scan. How much evolving within the universe will be noticeable within that 2 year run? My gut response is not much, but that's why we do the science to see the changes.<p>"designed to map the celestial sky in 102 infrared colors "<p>So I'm guessing the coolant used to make IR scanning possible will be the limiting factor on operational time span. This article didn't say where this satellite will be parked either, but wikipedia[0] shows it to be a geosync orbit. Would have been interesting to be able to design a replaceable coolant module to extend the observations to really make seeing the evolution possible. Obviously complexity adds to cost and design time, so of course they didn't. Just dreaming<p>As an example, the study of the stars orbiting around SagA* are very revealing, but have required > 10 years of observations.<p>[0] <a href="https://en.wikipedia.org/wiki/SPHEREx" rel="nofollow">https://en.wikipedia.org/wiki/SPHEREx</a>