- NASA Evolutionary Xenon Thruster (NEXT)
- Heatshield for Extreme Entry Environment Technology (HEEET)
- Deep Space Optical Communications (DSOC)
- Light Weight Radio-isotope Heater Units (LWRHUS)
- Advanced Solar Arrays (ASA)
- Deep Space Atomic Clock (DSAC)
- Green Propellant
- Autonomous Landing and Hazard Avoidance Technology (ALHAT)
There is also a 1% incentive for a student collaboration, which is a student-based addition to the mission such as an instrument or support software that requires the mission to take place, and whose failure would not compromise the main mission.
There are numerous other changes in this AO compared to past ones for the Discovery program. However, it is possible that one factor that will distinguish this competition from past ones isn't in the AO, but instead is from a changed landscape in the potential sources of Discovery mission proposals. A number of private groups have been trying to implement what seem to be roughly Discovery-class missions:
- B612 Foundation Sentinel Mission to survey near-Earth asteroids
- Boldly Go Institute Sample Collection to Investigate Mars (SCIM) mission to skim the Martian atmosphere and return dust samples to Earth
- Mars One Mars lander
In addition, private organizations have been working on robotic spacecraft for asteroids (Planetary Resources, Deep Space Industries, etc) and the lunar surface (Astrobotic, Moon Express, etc). In some cases their systems appear to be smaller than Discovery class, intended more for industrial use than science, and at the stage of technology demonstration, but perhaps they could piggy-back on a larger Discovery mission proposal, or a "swarm" of them could combine to make a Discovery class science mission.
A group at NASA has also studied a concept for a "Red Dragon" Mars lander. One might imagine that, if the mission aligns well with SpaceX's long-term goals, SpaceX might be willing to put some resources into such a proposal, giving that proposal a leg up in a Discovery competition similar to the private efforts of B612, Mars One, and Boldly Go for their missions.
Do I expect this round of Discovery to be won by one of these private teams? Not really. If I had to guess, I would guess that the winner will be a traditional industry/academia/NASA Discovery team. However, I do expect this round to feature more serious non-traditional private participation in the competition than in the past. Participation in this round would enable the teams to refined their mission proposals while allowing them more time to accumulate their own funding and to develop their own technologies, making them stronger competitors in future Discovery rounds.