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Lithium is also found in brown dwarf substellar objects and certain anomalous metal-poor stars. Because lithium is present in cooler, less massive brown dwarfs, but is destroyed in hotter red dwarf stars, its presence in the stars' spectra can be used in the "lithium test" to differentiate the two, as both are smaller than the Sun. [12] [13] [15]
The present measurement of helium-4 indicates good agreement, and yet better agreement for helium-3. But for lithium-7, there is a significant discrepancy between BBN and WMAP/Planck, and the abundance derived from Population II stars .
Lithium burning is a nucleosynthetic process in which lithium is depleted in a star. Lithium is generally present in brown dwarfs and not in older low-mass stars. Stars, which by definition must achieve the high temperature (2.5 × 10 6 K) necessary for fusing hydrogen , rapidly deplete their lithium.
Values of S(E 0) are typically 10 −3 – 10 3 keV·b, but are damped by a huge factor when involving a beta decay, due to the relation between the intermediate bound state (e.g. diproton) half-life and the beta decay half-life, as in the proton–proton chain reaction.
For all of NASA’s high-tech advancements, it may surprise you to know that the agency used regular kitchen aluminum foil to save one of its most famous missions.
Batteries are used on spacecraft as a means of power storage. Primary batteries contain all their usable energy when assembled and can only be discharged. Secondary batteries can be recharged from some other energy source, such as solar panels or radioisotope-based power (), and can deliver power during periods when the space vehicle is out of direct sunlight.
NASA responded to news that Boeing aims to lay off up to 400 workers from its Space Launch System program. The SLS rocket plays a key role in the Artemis moon program, the agency said..
The third most common use of lithium is in greases. Lithium hydroxide is a strong base, and when heated with a fat, it produces a soap, such as lithium stearate from stearic acid. Lithium soap has the ability to thicken oils, and it is used to manufacture all-purpose, high-temperature lubricating greases. [21] [162] [163]