What is NEOCam's (now NEO Surveyor) strategy for scanning the sky? Need to consider in which coordinate system?

Question

In Survey Simulations of a New Near-Earth Asteroid Detection System it can be seen that Infrared astronomer Amy Mainzer gave the scanning strategy of the horizon in a paper, but I am very confused whether the scanning strategy of the sky is the same? In addition, how to connect solar elongation with ecliptic latitude?

The main problem is that I cannot figure out which coordinate system to convert the position of the asteroid to.

Fig. 3.— The basic element of the survey cadence is a “quad,” which consists of four observations taken over ∼9 hours. The green rectangle indicates the starting position.

Answer 1

See also:

• What is the name of the new NEO searching telescope "heavily based on" NEOCam? (now NEO Surveyor)
• Why has the Earth-Sun libration point L1 been chosen over L2 for NEOCam (now NEO Surveyor) to detect new NEOs?

above: Profoundly not-to-scale illustration of NEOCam in an orbit around the Sun-Earth libration point L1, about 1.5 million kilometers from Earth. Presumably Sun-shield and Earth-shield block light (both infrared and visible) from the Sun and the Earth in order for the instrument to work at cold temperature necessary to detect the faint infrared light radiated from NEOs.

above: Infrared astronomer Amy Mainzer illustrates how asteroids warmed by the sun will stand out more brightly in the infrared compared to reflected visible light from the sun. One coffee cup is black the other white in the false-color infrared thermal image. From here.

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If you move on to figures 5 and 6 of Mainzer et al 2015 Survey Simulations of a New Near-Earth Asteroid Detection System it seems it's fairly clearly explained.

NEOCam will be in a heliocentric orbit in resonance with the Earth, in other words, in a halo orbit around Sun-Earth L1.

The paper discusses how close it should look to the direction of the Sun.

The reference plane for these illustration is the ecliptic with the horizontal direction indicating angle to the left or right of the Sun. The vertical direction is perpendicular to the ecliptic.

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Fig. 5.— The survey pattern over ∼6 days for the L1 survey. Green indicates the starting field.

Fig. 6.— The entire cadence takes ∼22 days to execute, switching back and forth on either side of the Sun for the L1 survey, and proceeding in a continuous sweep for the Venus-trailing survey.