Which faster engines are scientists building for Mars, and how close are they?

"Nuclear thermal propulsion can potentially reduce the time of flight and spacecraft system mass needed for human spaceflight beyond cislunar space."

"Реактор прошёл значительную серию испытаний, но ни разу не испытывался на полную длительность работы."

"Mars mission aims for nuclear propulsion—on a tight deadline (2026)"

"the canonical problem for nuclear propulsion has always been that its benefits are shadowed by low technology readiness of a complex system."

"Внереакторные узлы были отработаны полностью."

"comprises a 42-MWt-capable nuclear reactor core to provide 9.4 kN thrust on demand at a specific impulse of 940 s."

"27 марта 1978 года — первый энергетический пуск первого реактора ЯРД 11Б91. Мощность: до 25 МВт (примерно 1/7 от проектной) , температура водорода — до 1500 градусов Цельсия , время работы — 70 секунд."

"Earth-to-Mars orbital transfers less than 100 days appear feasible assuming 680,000 kg of liquid hydrogen propellant and a vehicle dry mass of 83,000 kg that includes the 13,000 kg CCNTR system."

"The reactor also produces up to 100 kWe power for the spacecraft, eliminating the need for solar power generation and averting challenges associated with restarting a cold reactor for propulsive burns."

"эскизный проект космической энергоустановки с ГФЯР ЭУ-610 мощностью 3,3 ГВт"

"The split-sprint nuclear electric propulsion system offers trip times comparable to nuclear thermal propulsion (NTP) systems, while providing mission abort opportunities that are not possible with "reference" mission architectures."

"while current approaches use only chemical rockets, it is important to study how a hybrid architecture affects performance."

"Conventional chemical propulsion systems have limitations for deep space exploration due to their limited specific impulse and extended transfer durations, which constrain payload capacity and mission flexibility."

"The NEP development project plan proposed includes evolutionary technology development for nuclear electric propulsion systems that expands upon SP-100 (Space Power - 100 kw e) technology that has been developed for lunar and Mars surface nuclear power"

"However, ongoing research suggests that NTP could play a significant role in enabling safer and more efficient interplanetary exploration within the coming decades."

"chemical Isp = 455 s, NTP Isp = 900 s"

"System upgrades are expected to evolve that will result in even shorter trip times, improved payload capabilities, and enhanced safety and reliability."

"it usually involves a 6-9 month one way trip."

"Most of the effects of these hazards can be reduced by reducing the transit time to Mars."

"Non-nuclear technology development for the NEP system is estimated to cost about $721 M (1993 $)."

"Unlike conventional chemical rockets that produce their energy through combustion, the NTR derives its energy from fission of Uranium-235 atoms contained within fuel elements that comprise the engine s reactor core."

"and was assigned to Los Alamos National Laboratory."

"Phoebus 2A ran for 12 minutes at 4100 MW demonstrating sufficient power is available."

"The requirements of nuclear thermal propulsion (NTP) are examined with respect to a specific mission scenario derived from Stafford Committee recommendations."

"Most of the effort was directed toward developing a solid-core, nuclear thermal rocket and examining a high-power nuclear electric propulsion system."

"The engine requirements call for a 50-75-klb engine-thrust level, maximum single burn time of 0.6 hours, and a maximum total-mission burn time of 1.7 hours."

"The committee considered several concepts and eventually recommended that further work be performed in the areas of gas core fission rockets, inertial confinement fusion systems, antimatter based rockets, and gas core fission electric systems."

"Proven nuclear thermal rocket (NTR) technology, with its high thrust and high specific impulse (Isp ~900 s), can cut 1-way transit times by as much as 50 percent by increasing the propellant capacity of the Mars transfer vehicle (MTV)."

"This paper presents stage performance and requirements for a nuclear thermal rocket (NTR) Mars transportation system to support the human Mars mission of the SEI."

"For a crew of 6, a 475-day total-mission trip with a 90-day stay at Mars is possible."

"Following the committee's recommendations, some computational modeling work has been performed at Los Alamos in certain of these areas and critical issues have been identified."

"No large technology scale-ups in engine size are required for these short transit missions either since the smallest engine tested during the Rover program—the 25 klbf “Pewee” engine is sufficient when used in a clustered arrangement of three to four engines."

"The opposition class mission is associated with relatively short Mars stay times ranging from 30 to 90 days and total mission duration of 350 to 600 days."

"other mission-performance issues considered include propulsion-technology assumptions, triple-perigee earth-departure burns, and Mars parking-orbit selection"

"Although the initiative did not exist long enough to allow substantial technology development"

"The baseline Copernicus design is capable of 1-way transit times ranging from ~150 to 220 days depending on the particular opportunity. For the 2033 mission, 150-day transit times are possible."

"Cutting the transit times in half to 90-days increases the Mars stay time to ~673 days, but decreases the round trip time to ~853 days. The mission V budget however, increases by ~250 percent to ~15.175 km/s! While challenging, transit times this short are possible using NTP."

"The hydrogen propellant is then exhausted through a nozzle to realize specific impulses of 3000 s."