Because of the low production volume of orbiters, the Space Shuttle program decided to build a vehicle as a Structural Test Article, STA-099, that could later be converted to a flight vehicle. The contract for STA-099 was awarded to North American Rockwell on July 26, 1972, and construction was completed in February 1978. After STA-099’s rollout, it was sent to a Lockheed test site in Palmdale, where it spent over 11 months in vibration tests designed to simulate entire shuttle flights, from launch to landing. To prevent damage during structural testing, qualification tests were performed to a safety factor of 1. 2 times the design limit loads. The qualification tests were used to validate computational models, and compliance with the required 1. 4 factor of safety was shown by analysis. STA-099 was essentially a complete airframe of a Space Shuttle orbiter, with only a mockup crew module installed and thermal insulation placed on its forward fuselage.
Makemake is about a fifth as bright as Pluto. However, despite its comparative brightness, it was not discovered until well after a number of much fainter KBOs had been detected. Most of the scientific hunts for minor planets are conducted relatively close to the region of the sky that the Sun, Earth's Moon, and planets appear to lie in (the ecliptic). This is because there is a much greater likelihood of discovering objects there. Makemake is thought to have evaded detection during earlier searches because of its relatively high orbital inclination, as well as the fact that it was at its greatest distance from the ecliptic at the time of its discovery--in the northern constellation of Coma Berenices. The Face Behind The Veil. Titan is a little larger than Mercury--the smallest major planet inhabiting our Solar System. Indeed, Titan would have been classified as a major planet in its own right if it orbited our Sun instead of Saturn. The Huygens Probe images lifted the veil from the face of this distant moon-world, revealing a youthful surface that is both smooth and relatively free of impact craters. Huygens also found that this icy, hydrocarbon-saturated moon's climate includes those heavy rains of gasoline, as well as raging, roaring winds. Some of Titan's surface features were found to be hauntingly akin to certain surface features on Earth. Therefore, even though Enceladus is only Saturn's sixth-largest moon, it is amazingly active. Because of the success of the Cassini mission, scientists now know that geysers spew watery jets hundreds of kilometers out into Space, originating from what may well be a vast subsurface sea. These jets, which erupt from fissures in the little moon's icy shell, whisper a siren's song to bewitched astronomers. This is because the jets suggest that the icy moon may harbor a zone where life might have evolved. The jets dramatically spray water ice from numerous fissures near the south pole, that have been playfully termed "tiger stripes." The "tiger stripes" look like giant scratches made by a tiger's raking claws.