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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]
In physical cosmology, Big Bang nucleosynthesis (also known as primordial nucleosynthesis, and abbreviated as BBN) [1] is a model for the production of light nuclei, deuterium, 3 He, 4 He, 7 Li, between 0.01s and 200s in the lifetime of the universe. [2]
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.
The decay of the vacuum of space will occur if the Higgs field tunnels, like skipping the line, to a higher overall energy setting. Our universe has an overall equilibrium that will shred apart if ...
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.
Nucleosynthesis in stars and their explosions later produced the variety of elements and isotopes that we have today, in a process called cosmic chemical evolution. The amounts of total mass in elements heavier than hydrogen and helium (called 'metals' by astrophysicists) remains small (few percent), so that the universe still has approximately ...
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..
While Barbie added "astronaut" to her long list of careers in 1965 — four years before man landed on the moon — this marks the first time in the doll's 63-year history that Barbie dolls were ...