100% | NASA | 4 | Earth Observing System org. |
41% | SETI | 4 | Org. seeking life beyond Earth |
40% | SETI | 4 | Org. concerned with life beyond Earth |
40% | NSA | 3 | Org. protecting U.S. information systems |
39% | ECM | 3 | System of organizing documents of an org. |
39% | CTA | 3 | Org. that operates the El train system |
39% | SEPTA | 5 | Org. that operates Philadelphia’s rail system |
38% | EPA | 3 | Org. created the same year as Earth Day |
38% | SUNS | 4 | Earth has one, other solar systems have multiple |
37% | MTA | 3 | Org. phasing out its MetroCard payment system by 2023 |
36% | RHESUS | 6 | Blood group system first observed in monkeys |
36% | EPA | 3 | Org. created the same year as the first Earth Day |
35% | MARS | 4 | Planet next to Earth in the solar system |
35% | UNIVERSE | 8 | Entirety of Earth, our solar system, and beyond |
35% | ECOSPHERE | 9 | Closed system that includes all life on Earth |
35% | GSA | 3 | School org. that might observe Day of Silence |
35% | EPA | 3 | Org. established eight months after the first Earth Day in 1970 |
34% | MARS | 4 | Red planet next to Earth in the Solar System |
34% | DST | 3 | Annual system that Puerto Rico doesn't observe: abbr. |
32% | EPA | 3 | Government org. created the same year as the first Earth Day |
31% | ECO | 3 | Earth-friendly prefix with "system" |
31% | SOLAR | 5 | ___ system (Earth's place) |
31% | SOLAR | 5 | __ system (Earth's place) |
31% | SOLAR | 5 | ___ system (Earth's home) |
31% | EPA | 3 | Government org. created the same year as the first Earth Day (Abbr.) |
29% | ECO | 3 | Earth-friendly prefix for "sphere" or "system" |
29% | LRT | 3 | Org. responsible for public bus and rail systems in the UK capital in the '90s (abbr.) |
29% | GPS | 3 | Navigational system involving satellites used to determine the position of a receiver on Earth |
28% | GALAXY | 6 | Milky Way ___, star system with Earth whose name translates to "Milky Way Milk" in Greek |
26% | WATCHING | 8 | Observing |