...
One major understudied element of spaceflight effects on visual acuity is the hypergravity environment of launch. ISS biometric monitoring including high-resolution 3-Tesla magnetic strength MR imaging of head and orbits are only collected “prior to and assoon as possible after spaceflight” (Lee et al., 2020). Several functional barriers prevent in-vivo investigation of ocular performance during launch including lack of instruments aboard launch vehicles to perform necessary biomedical monitoring such as Amsler grid, ophthalmoscopy, tonometry, fundus photography, orbital ultrasound and OCT—all available on the ISS (Lee et al., 2020). Additionally, the necessity for astronautsto remain restrained to their seats for launch safety and perform vehicle-related activity during launch limit the scope of visual acuity monitoring that may be performed during launch.
To address this gap in spaceflight hypergravity effects on visual acuity, Cyclops is a proposed sounding rocket payload experiment investigating of the biomechanical effects of hypergravity on the SANS symptom of hyperopic globe flattening of an in-vitro B. taurusocular specimen. Cyclops will specifically test the hypothesis that launch and landing conditions contribute significant gravity-induced ocular pressure in addition toICP by observing whether the amount of globe flattening observed during a sounding rocket flight is on the order of overall globe flattening levels measured in SANS-affected astronauts.
Globe flattening shall specifically be characterized through repeated in-flight axial imaging of the specimen to produce a relationship between axial length change and hypergravity pressure(Sibony et al., 2023). An example of an ultrasound globe flattening observation is provided in Figure 1., though an in-vitro sample will allow for traditional optical imaging to measurement of globe flattening without need for ultrasound.
Figure 1. Schematic of hyperopic globe flattening to be measured with Cyclops. Adapted from
Velezet al., 2017.
The payload is designed to be approximately 10 lbs. and stored within in a standard 3U Cubesat dispenser (contained completely within dims ions of 10x10x30 cm). The payload is additionally designed to be able to integrate modularly with the rest of the vehicle, with minimal interference with launch operations.