argon electric propulsion
51Pebble bed reactor — Sketch of a pebble bed reactor in Italian …
52Vacuum — This article is about empty physical space or the absence of matter. For other uses, see Vacuum (disambiguation). Free space redirects here. For other uses, see Free space (disambiguation). Pump to demonstrate vacuum In everyday usage, vacuum is… …
53Oxygen — This article is about the chemical element and its most stable form, O2 or dioxygen. For other forms of this element, see Allotropes of oxygen. For other uses, see Oxygen (disambiguation). nitrogen ← oxygen → fluorine ↑ O ↓ …
54Dwayne A. Day — Dwayne Allen Day is an American space historian and policy analyst and served as an investigator for the Columbia Accident Investigation Board. Day works for the Space Studies Board of the National Research Council/National Academy of Sciences,… …
55Список лауреатов медали Румфорда — Не следует путать с Премией Румфорда[ru] …
56Manned mission to Mars — Concept for NASA Design Reference Mission Architecture 5.0 (2009) A manned mission to Mars has been the subject of science fiction, engineering, and scientific proposals throughout the 20th century and into the 21st century. The plans comprise… …
57Pioneer 10 — Künstlerische Darstellung der Pioneer 10 im Weltraum Künstlerische Darstellun …
58INS Hanit (503) — INS Hanit INS Hanit Banderas …
59Gas — This article is about the physical properties of gas as a state of matter. For the uses of gases, and other meanings, see Gas (disambiguation). Ga …
60oxidation–reduction reaction — ▪ chemical reaction Introduction also called redox reaction any chemical reaction in which the oxidation number of a participating chemical species changes. The term covers a large and diverse body of processes. Many oxidation– reduction… …
