Translation:The red stone is a very important object.
The PGM-11 Redstone was the first large American ballistic missile. A short-range ballistic missile (SRBM), it was in active service with the United States Army in West Germany from June 1958 to June 1964 as part of NATO's Cold War defense of Western Europe. It was the first missile to carry a live nuclear warhead, in the 1958 Pacific Ocean weapons test, Hardtack Teak. Chief Engineer Wernher von Braun personally witnessed this historic launch and detonation.
When an adjective is used attributively (= placed before the noun) with a definite noun, it takes what you know as the plural form - even in the singular.
et rødt hus (indefinite singular)
det røde huset (definite singular, attributive adjective)
huset er rødt (definite singular, predicative adjective)
"røde" would also be used for all plurals.