Origins is a Mid IR to Far IR Astrophysics Flagship (multi-$B) Mission that has been studied over the last 2 years by NASA for potential flight in the mid 2030’s. The wavelength range of interest for this mission is 3 to 600 microns, with an objective of having a noise floor of the sky background for this range. This means cooling the telescope to nearly 4 K. The telescope size/collecting area is set by the proposed transiting exoplanet spectral survey at a minimum of 5 meters in diameter. This is about the size of the James Webb Space Telescope, but 10 times colder. This paper describes the architecture and selections made, and technology paths for cooling the telescope, instruments, and detectors to reach a sensitivity in the far-IR that is 4 orders of magnitude better than anything flown before.