Once they have exhausted their supply of hydrogen through nuclear fusion, medium to low mass stars shed their outer layers to form a planetary nebula and evolve into white dwarfs.

Once the hydrogen fuel at the core is exhausted, a star with at least 0. 4 times the mass of the Sun expands to become a red giant, in some cases fusing heavier elements at the core or in shells around the core.

Once on the ground, snow can be categorized as powdery when light and fluffy, fresh when recent but heavier, granular when it begins the cycle of melting and refreezing, and eventually ice once it packs down, after multiple melting and refreezing cycles, into a dense mass called snow pack.

Once the mass is displaced from its equilibrium position, it experiences a net restoring force.

Once this happens, the links between scientific theory, engineering practice and mass production that measurement provides can be missing from the start on new work or eventually lost on old work.

Once inserted, the operational balloon would have a total mass of no more than and would remain operational for a week.

Once it reaches maturity, the Phoenix Force takes over its host, going on to cause mass destruction.

Once emptied, a mass sepulchre would be used again, but even then, the earth was already filled beyond saturation with decomposing human remains.

Once this had occurred, Napoleon would mass his reserves at the hinge of that right angle and launch a heavy attack to break the lines.

Once the system cools to normal temperatures and returns to ground states in terms of energy levels, there is less mass remaining in the system than there was when it first combined and was at high energy.

Once installed, Emulator was rarely removed as it could run the machine as desired and, as almost every machine function was used, it was physically heavy from the sheer mass of installed jumpers filling nearly the entire board.

Once understood, the conservation of mass was of great importance in changing alchemy to modern chemistry.

Once a star with about 0. 5 – 10 times the mass of the Sun has consumed nearly all the hydrogen at its core, it begins to evolve up the red giant branch.

Once the embryo has reached the blastocyst stage, it is composed of several parts, mainly the trophectoderm, the inner cell mass, and the primitive endoderm.

Once the critical mass is assembled, at maximum density, a burst of neutrons is supplied to start as many chain reactions as possible.

Once the mass of material is known, the particular type of anode is chosen.

Once the notion that the universe started with a rapid inflation nicknamed the Big Bang became accepted by the majority of scientists, the ultimate fate of the universe became a valid cosmological question, one depending upon the physical properties of the mass / energy in the universe, its average density, and the rate of expansion.

Once the cores are of sufficient mass ( 5 – 10 Earth masses ), they begin to gather gas from the surrounding disk.

Once that approval is obtained, the seeds are mass produced, and sold to farmers.

Once arctic air moves over an unfrozen ocean, the air mass modifies greatly over the warmer water and takes on the character of a maritime air mass, which reduces the strength of the high-pressure system.

Once an air mass moves away from its source region, underlying vegetation and water bodies can quickly modify its character.

Once the great mass of ice had melted, the subsequent unburdening of the Earth's crust resulted in a continuing rise in the land which is estimated to be of the order of 2 – 3 mm per year.

Once the digitization process is completed, automatic functions create new carrier database records, insert metadata, direct the new archive and browsing files to their final mass storage locations, and link files to the MARC based database for direct access.

Once glycogen is depleted the body begins to fuel the brain using ketones, while also metabolizing body protein ( including but not limited to skeletal muscle ) to be used to synthesize sugars for use as energy by the rest of the body.

Once in production, the 912E was powered by an 86 bhp 2. 0 L Volkswagen air-cooled engine, refined with a new Bosch L-Jetronic ( Air Flow Controlled ) fuel injection system.

Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula.

Once the universe had cooled sufficiently, half of the remaining half ( one quarter of the original energy ) of the intelligent beings ' fuel reserves would once again be released, powering a brief period of thought once more.

Once fuel, maintenance, and insurance costs are taken into account, the operating costs of an FSTD are usually substantially lower than the operating costs of the simulated aircraft.

Once vaporized, the fuel combines with oxygen in the atmosphere to form a flame.

Once the victims were no longer able to move, the soldiers covered their bodies with fuel and set the barns on fire.

Once the crack had penetrated the inner bore, fuel started leaking onto the road.

Once fuel, maintenance, and insurance costs are taken into account, the operating costs of an FSTD are usually substantially lower than the operating costs of a simulated aircraft.

Once the first line of containment is breached during a reactor plant accident, there is a possibility that the fuel or the fission products held inside can be released into the environment.

Once ready stocks of weapons and fuel are depleted, logistic concerns are often exported to civilian policy-makers.

Once the fuel elements of a reactor begin to melt, the primary containment has been breached, and the nuclear fuel ( such as uranium, plutonium, or thorium ) and fission products ( such as cesium-137, krypton-88, or iodine-131 ) within the fuel elements can leach out into the coolant.

Once delivered to site, it requires only the steam, water pipe work, fuel supply and electrical connections to be made for it to become operational.

Once separated and purified of any contaminants and impurities, the fuel or lubricant can be sold without further processing.

Once released, the engine runs at a more-or-less constant speed until the fuel runs out, or, if equipped, the fuel-shutoff is activated.

Once these determinations have been made, the operator develops a route that is the most time and fuel efficient while respecting all applicable safety concerns — thereby maximizing both the aircraft's and the airspace's overall performance capabilities.

Once the Earth Return Vehicle lands it is planned to use an onboard Sabatier reactor in order to create liquid oxygen and methane fuel for the return trip ; a second spacecraft, carrying the crew, would follow after.

Once installed, the waste heat generated by the fuel cell will be converted into hot water to be used in campus buildings.

Once a generator is running, it can power the complex without stopping as long as it has fuel.

Once full, they do not require more fuel when in orbit.

Once the fuel and oxidizer were being pumped and burning, the process was self-sustaining until engine shutdown.