No Scarcity of Goals: Mission Hyreus (1993)

In Greek mythology Hyreus (pronounced “HY-ree-us”) is Orion’s father. College students within the College of Washington (UW) Division of Aeronautics and Astronautics had a unique tackle this obscure determine, nonetheless. The tip of the Chilly Warfare and efforts to rein in a galloping U.S. Federal deficit yielded a decline in aerospace spending within the late Nineteen Eighties/early Nineties. This led to “downsizing” and company mergers in aerospace trade. New hires slumped, confronting aerospace engineering college students with an unsure future.

Based on the 28 UW college students who contributed to the 1993 Mission Hyreus report, Hyreus (pronounced “HIRE-us”) was a mortal who succeeded in dwelling off the land within the barren underworld, and for that achievement was made the God of Gainful Employment. The scholars carried out the Mission Hyreus Mars Pattern Return (MSR) examine in UW’s House Techniques Design course as a part of the NASA/Universities House Analysis Affiliation (USRA) Superior Design Program (ADP). Dr. Adam Bruckner was their teacher. 

Hyreus was a follow-on to UW’s 1992 Mission Minerva NASA/USRA ADP examine, which proposed a piloted Mars expedition based mostly on the 1990 Martin Marietta Mars Direct plan. The Minerva examine had discovered possible Mars Direct’s reliance on Earth-return rocket propellants manufactured from martian assets, a method referred to as In Situ Propellant Manufacturing (ISPP). Within the Mars Direct, Minerva, and Hyreus plans, ISPP relied on carbon dioxide gasoline within the martian ambiance as a result of it’s available everywhere in the planet. Carbon dioxide makes up about 95 % of the martian ambiance, which is just about 1 % as dense as Earth’s ambiance. 

The UW college students emphasised a Sabatier/Reverse Water-Fuel Shift (RWGS) ISPP system, which might produce liquid methane gas and liquid oxygen oxidizer, although in addition they examined a carbon monoxide ISPP system. The UW college students defined that Hyreus aimed to display ISPP expertise in a crucial mission function at a comparatively low price forward of a piloted ISPP Mars mission. 

Assuming that Hyreus succeeded, the mission would exploit the mission-enhancement potential of ISPP by returning to Earth a Mars floor pattern with a mass of from 25 to 30 kilograms — that’s, another than 10 instances bigger than in most different MSR proposals. Evaluation of such a big pattern would allow scientists to find water deposits and search life on Mars, the scholars contended.

Hyreus Sabatier/Reverse Water-Fuel Shift (RWGS) In Situ Propellant Manufacturing (ISPP) system. Picture credit score: College of Washington Division of Aeronautics and Astronautics.

The 400-kilogram Sabatier/RWGS ISPP plant would wish a complete 122 kilograms of cryogenic liquid hydrogen feedstock introduced from Earth. The hydrogen would regularly boil and escape, so Hyreus would depart Earth with an additional 88 kilograms on board to make up for losses. 

The Sabatier/RWGS plant would absorb dust-laden martian air at a price of 9.6 kilograms per day. The air would go by a hydrocyclone mud filter to a compressor, then to a condenser that will liquify its carbon dioxide. Residual hint gases (nitrogen and argon) could be vented overboard, and the carbon dioxide could be pumped to the ISPP unit. There it could be mixed with 0.24 kilograms of liquid hydrogen feedstock per day to supply carbon monoxide gasoline and water. 

The plant would vent the carbon monoxide overboard and pump the water to an electrolyzer, which might break up it into gaseous hydrogen and oxygen. The oxygen, produced at a price of 4.62 kilograms per day, would go to a liquifier, then to its closing vacation spot within the Earth Return Automobile (ERV) oxidizer tank. 

The hydrogen, in the meantime, would go to the Sabatier reactor, the place it could be joined with martian carbon dioxide within the presence of a nickel or ruthenium catalyst to yield water and methane gasoline at a price of 1.15 kilograms per day. The methane would go to a liquifier, then to the ERV’s twin gas tanks. The water, in the meantime, would return to the electrolyzer. Over 1.4 years the Sabatier/RWGS ISPP system would produce 480 kilograms of methane and 1921 kilograms of oxygen for the ERV’s single rocket engine. 

The scholars discovered that the carbon monoxide ISPP system had two benefits over the Sabatier/RWGS system: it could want no Earth-supplied feedstock and could be smaller, less complicated, and fewer huge (simply 300 kilograms). Then again, the carbon monoxide and oxygen it produced constituted a propellant mixture much less environment friendly than methane/oxygen. This meant that the carbon monoxide ISPP plant would wish to fabricate 3440 kilograms of carbon monoxide and 1960 kilograms of oxygen to make up for the diminished efficiency.

Each ISPP programs would rely for electrical energy on a nuclear-fueled Dynamic Isotope Energy System (DIPS) connected to the ERV. The DIPS would additionally energy different MLV programs. The Sabatier/RWGS and carbon monoxide ISPP programs would draw from the DIPS 1.2 and 1.1 kilowatts of electrical energy, respectively. 

Touchdown its hydrogen feedstock and heavy ISPP unit on Mars would imply the Sabatier/RWGS Hyreus spacecraft would wish a sturdier lander construction, a bigger aerobrake, bigger parachutes, and extra touchdown propellant than the carbon monoxide Hyreus spacecraft. The carbon monoxide Hyreus would, however, want a bigger ERV to allow it to carry sufficient carbon monoxide/oxygen propellants to succeed in Earth. The scholars calculated that the Sabatier/RWGS Hyreus would have a mass of 4495 kilograms at launch from Earth; the carbon monoxide Hyreus mass would complete 4030 kilograms. 

Hyreus “raked sphere-cone” aerobrake. Picture credit score: College of Washington Division of Aeronautics and Astronautics.

At launch, the Hyreus spacecraft would comprise an aerobrake and a Mars Touchdown Automobile (MLV) bearing the Satellite tv for pc Commentary and Communication at Mars (SOCM) orbiter, Particular Planetary Commentary Transport (SPOT) rover, and the ERV. Hyreus would go away Earth between 22 Might and 20 June 2003 on a $400-million, 940-metric-ton Titan IV/Centaur rocket, essentially the most highly effective U.S. launcher anticipated to be obtainable. 

Two solid-propellant rocket motors would enhance the Titan IV off the launch pad, then the primary stage would kick in somewhat greater than two minutes after liftoff. Throughout first-stage operation, the 7.5-meter-diameter launch shroud would break up and fall away, exposing Hyreus atop the Centaur higher stage. After Titan IV second stage separation, the Centaur would fireplace to position itself and the Hyreus spacecraft into parking orbit 300 kilometers above Earth. 

The Hyreus aerobrake would come with two folding “flaps” in order that it may match inside the confines of the Titan IV launch shroud. After arrival in parking orbit, the flaps would hinge into place and lock to provide the 11.3-meter-long aerobrake its full 9.4-meter width. The scholars selected a “raked sphere-cone” aerobrake over one with a biconic form as a result of it could be 20% lighter and have an open again that will provide extra choices for deploying the SOCM orbiter. 

A second Centaur burn would push Hyreus out of parking orbit towards Mars, then the Centaur would detach and fireplace its engine a closing time to keep away from placing and contaminating the planet. Relying on the precise Earth launch date, Earth-Mars switch would final from 188 to 217 days. Hyreus would carry out course corrections through the switch utilizing the MLV’s 4 descent rocket motors. 

On 25 December 2003, Hyreus would enter the ambiance of Mars touring at 5.69 kilometers per second. Aerodynamic drag would sluggish the spacecraft so Mars’s gravity may seize it into the specified near-polar orbit. Hyreus would descend to an altitude of 55 kilometers, then would skip out of the ambiance and climb to apoapsis (the excessive level of its orbit) 2470 kilometers above Mars. There the MLV descent rockets would ignite briefly to elevate the spacecraft’s periapsis (the low level of its orbit) out of the ambiance to an altitude of 250 kilometers. 

Mars would rotate beneath the orbiting Hyreus spacecraft, regularly positioning the chosen touchdown web site in order that descent may start. A second apoapsis burn would put Hyreus on target for its second aerobraking maneuver, which might place it into an orbit with a 580-kilometer-high apoapsis and a periapsis beneath the martian floor close to the deliberate touchdown web site. 

Following the second apoapsis burn, Hyreus would deploy the 282-kilogram SOCM orbiter. After deployment, SOCM would fireplace thrusters to boost its periapsis to 580 kilometers and circularize its orbit. The solar-powered SOCM would carry a Floor-Penetrating Radar to hunt subsurface water and a wide-angle digital camera for monitoring climate on the MLV touchdown web site. The orbiter would transmit its knowledge to the MLV for relay to Earth. 

After the second apopasis burn, the Hyreus spacecraft would fall towards its touchdown web site. The scholars proposed three candidate websites inside 15° of the martian equator. Close to-equatorial websites have been most well-liked, they argued, as a result of the planet’s rotation would give the ERV an additional enhance when the time got here for it to elevate off from the planet. All the touchdown websites included clean areas massive sufficient to allow a protected off-target touchdown, in addition to quite a lot of sampling websites inside rover vary (~20 kilometers) of the MLV. 

The UW college students’ prime Hyreus touchdown web site was at 148.1° W, 13.8° S in Mangala Valles, a 350-kilometer-long outflow channel. Along with the channel itself, Mangala included younger volcanoes, historic rocks, and younger and previous influence craters. The primary backup Hyreus web site was at 63° W, 16° N in Valles Marineris, a system of vast, deep canyons with horizontally layered partitions. The second backup, at 45° W, 20° N, was in Chryse Planitia, an historic flood plain close to the positioning the place Viking 1 set down on 20 July 1976. The scholars famous {that a} go to to the derelict Viking 1 lander “would provide the possibility to get first hand evaluation of the aeolian and different climate results on the lander over the 20 years it has been there.” 

Hyreus Mars Touchdown Automobile (MLV) entry, descent, and touchdown. Picture credit score: College of Washington Division of Aeronautics and Astronautics.

Hyreus MLV in Mars touchdown configuration. The drawing is considerably inaccurate; by the point the MLV rested on its deployed touchdown gear on the floor of Mars the SOCM orbiter and parachute canister could be absent. Picture credit score: College of Washington Division of Aeronautics and Astronautics.

The aerobrake would sluggish the Hyreus MLV to a velocity of 220 meters per second 10 kilometers above Mars, then a tractor rocket would deploy the lander’s first parachute. Because it unfurled, explosive bolts would fireplace to jettison the aerobrake. 

Two extra parachutes would deploy eight kilometers above Mars. The parachute cluster would sluggish the MLV to 40 meters per second 500 meters above the touchdown web site. Explosive bolts would then fireplace to jettison the MLV’s higher structural body and the connected parachute cluster, exposing the ERV. 4 throttleable touchdown rockets would ignite a second later. 

The MLV would really feel a most deceleration of 6.5 instances Earth’s gravity as its 4 footpads contacted Mars. At landing, the MLV would have a mass of 2650 kilograms.

Mars floor operations would final from 547 to 574 days. The Hyreus mission would give attention to the three Mars floor actions. The primary, ERV propellant loading, would start instantly after touchdown. Controllers on Earth would take a look at and activate the Sabatier/RWGS ISPP plant. Valves would open to confess martian air into the hydrocyclone filter and launch hydrogen feedstock. The electrolyzer would swap on after it stuffed with water, then the Sabatier reactor would activate after it acquired adequate hydrogen from the electrolyzer. Until a malfunction occurred, the ISPP plant would fill the ERV’s propellant tanks with out human intervention after it was switched on.

The second main Mars floor exercise, pattern acquisition, could be the first job of the 185-kilogram SPOT rover. SPOT would comprise three sections one meter vast by 0.44 meters lengthy joined by ball-and-socket joints. Every part would come with one pair of 0.5-meter-diameter wire wheels. Hub-mounted electrical motors would independently energy the wheels on the entrance and center sections, whereas the wheels on the rear (“trailer”) part could be passive rollers.

Hyreus Particular Planetary Commentary Transport (SPOT) rover. Picture credit score: College of Washington Division of Aeronautics and Astronautics.

SPOT’s entrance part would carry a pair of cameras for science and navigation and a Distant Manipulator Arm (RMA) with 4 interchangeable sampling instruments. These would come with a scoop/grabber (“scoobber”). The trailer part would come with a big drill for subsurface sampling. After SPOT collected a pattern, it could seal it inside a Cylindrical Pattern Assortment Cell (CSCC) and place it right into a pattern storage bay in its entrance part. 

Upon return to the MLV, the SPOT RMA would hand the CSCCs one by one to an RMA on the MLV for switch to the ERV. The ERV would preserve the samples at martian ambient temperature to assist hold them pristine. 

The third space of Mars floor exercise could be MLV science. The MLV would carry 57.1 kilograms of science tools, together with three exobiology experiments, a seismometer (to be deployed by SPOT at the least 200 meters from the MLV in order that vibration from the ISPP system wouldn’t intervene with it), a digital camera, a climate station, a mass spectrometer, and an RMA with 18 interchangeable instruments.

After 1.4 years of operation, the Sabatier/RWGS ISPP plant would run out of hydrogen and shut down. Controllers on Earth would then put together the ERV for liftoff. The first launch window for Mars departure would span from 25 June to 21 July 2005. Within the occasion of difficulties (for instance, if ISPP wanted extra time than anticipated), then launch from Mars could be postponed till the 19 June-22 August 2007 launch window opened. 

Explosive bolts would sever connections linking the ERV to the MLV, then the ERV’s RL-10-derived engine would ignite to launch it right into a 300-kilometer round parking orbit about Mars. The ERV would orbit Mars till it reached the right level in its orbit for Mars-Earth switch orbit injection, then would ignite its engine once more to place itself on target for Earth. Throughout Mars-Earth switch, it could place itself in order that the Apollo-style bowl-shaped aerobrake on its Earth Return Capsule (ERC) would shade the samples from the Solar. 

Assuming an on-time launch from Mars, the Hyreus ERV would attain Earth’s neighborhood on 31 March 2006. If launch have been delayed to 2007, Earth arrival would happen on 29 April 2008. The battery-powered ERC would separate from the ERV, then the latter would fireplace its engine a closing time to bend its course away from Earth. This Contamination and Collision Avoidance Maneuver would, the scholars wrote, forestall Mars mud and potential microbes on the ERV’s exterior from reaching the homeworld. 

Shielded by its aerobrake, the Hyreus ERC would enter Earth’s higher ambiance at a velocity of 11.2 kilometers per second. Atmospheric drag would sluggish it to 7.8 kilometers per second in order that Earth’s gravity may seize it, then a quick rocket burn would circularize its orbit at 340 kilometers of altitude for restoration by a House Shuttle orbiter. 

The scholars acknowledged that direct ERC entry into Earth’s ambiance adopted by a parachute descent to the floor would price lower than orbital restoration by a Shuttle, however opted for the latter as a result of it could allow astronauts to securely examine the Mars samples exterior of Earth’s biosphere. If their preliminary evaluation indicated that the Mars samples posed a hazard to life on Earth, the Shuttle crew may connect the ERC to a Payload Help Module solid-propellant rocket motor and eliminate it in deep house. 

The UW college students introduced their Hyreus examine in July 1993 on the eighth NASA/USRA ADP summer time convention close to NASA’s Johnson House Middle (JSC) in Houston, Texas. Not coincidentally, NASA JSC and contractor engineers have been additionally learning ISPP MSR mission designs presently. They discovered the UW college students’ work sufficiently spectacular to ask for a briefing at NASA JSC. NASA engineers subsequently cited the Hyreus report in NASA ISPP MSR paperwork. The God of Gainful Employment smiled upon the Hyreus college students; a number of subsequently discovered jobs at NASA facilities and with aerospace contractors. 

Sources

“Mars Rover Pattern Return Mission Using In Situ Manufacturing of the Return Propellants,” AIAA 93-2242, A. P. Bruckner, L. Nill, H. Schubert, B. Thill, and R. Warwick; paper introduced on the AIAA/SAE/ASME/ASEE twenty ninth Joint Propulsion Convention and Exhibit in Monterey, California, 28-30 June 1993. 

Mission Hyreus: Mars Pattern Return Mission Using In Situ Propellant Manufacturing Last Report, NASA/USRA Superior Design Program, Division of Aeronautics and Astronautics, College of Washington, 31 July 1993.

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