Photo from SpaceX webcast of the Psyche launch from Pad 39A. Love my cup of morning coffee
Mission Rundown: Falcon Heavy 7 - Psyche
Written: October 13, 2023
Psyche’s six year journey
SpaceX will be launching the Psyche mission for NASA on a Falcon Heavy rocket. This Falcon Heavy is composed of a new block 5 center core ‘B1079-1’ and the two flight proven block 5 side boosters; B1064-3 and B1065-3.
Psyche launched at 10:19 EDT - 14:19 UTC on October 13, 2023. The Falcon Heavy will be lifting off from Launch Complex 39A at the Kennedy Space Center in Florida.
Graphic from Flight Club showing FH8 ascent profile with booster separation, boostback, reentry and landing burns, while the core booster continues until MECO, stage separation and 2nd stage ignition. Fairing jettison isn’t shown like the fairing recovery area and the core booster crash site
After burning for about 2 minutes and 29 seconds, the side boosters will separate from the core booster and return to Florida and land on LZ-1 and LZ-2 at CCSFS.
The core booster will keep burning for about 1 minute and 20 seconds before shutting down and separating from the second stage, which will continue burning until reaching orbit velocity and coast to the continent of Africa and the Equator.
The core booster will crash about 1500 Km downrange in the Atlantic Ocean. Compared to FH3 with STP-2 with its attempt to land on OCISLY some 1236 km downrange, that extra burntime gives a 21% increase in range and thereby performance of its payload.
The Falcon Heavy is scheduled to fly two more missions this year. The USSF-52 mission was scheduled for launch on or about June 23, but that was delayed along with the NASA Psyche asteroid probe launch which was targeted for july.
Map made by Raul from the NGA notice. Side booster will land on LZ-1 and LZ-2. Fairing recovery zone is 1600 km downrange. The Core booster crash site is only ~1500 km downrange
Photo of Falcon Heavy 8 viewed in details - A contemporary graphic picture can be found here
Falcon Heavy will have completed its eighth mission since the first testflight.
SpaceX did perform a static fire test of the Falcon Heavy 8 with Psyche at 09:00 EDT on September 30, 2023 while waiting for its launch out of Cape Canaveral.
Falcon Heavy is constructed by joining of three Falcon 9 boosters side by side with a central long mission duration second stage carrying the payload into orbit.
The side boosters B1064 and B1065 will after detachment do a ‘boost back’ burn to Cape Canaveral. A re-entry burn will slow down the boosters and protect them from heating, and a landing burn to land the side boosters at Landing Zones 1 and 2, from where they will be made ready by minor refurbishments in preparations for their fourth flight.
The center core B1079-1 is flying bareback without landing legs; grid fins and using an old white interstage just like on the previous three Falcon Heavy missions. The center core will be expended to offer additional performance to the payload.
After second stage separation the Merlin vacuum engine ignited followed by the payload fairing separation. The second stage first burn will inject Psyche into a near-circular low-Earth parking orbit. The second stage doesn’t have a mission extension package since the second stage is painted all white.
That extension package is a gray stripe, which helps keep the RP-1 warm in sunlight, an increased number of composite-overwrapped pressure vessels (COPVs) for pressurization control, and additional TEA-TEB canisters for 3-5 relights of the vacuum engine.
After a 46 minute long coast period halfway around the world, the Mvac’s second burn will inject Psyche into a heliocentric orbit. Psyche will after deployment use its own onboard ion propulsion to intercept the asteroid Psyche after a six year journey.
The fairings are both new, flying for the first time on this mission, and will be recovered ~1553 km downrange by recovery vessel Bob, who will lift both fairings out of the water and sail them back for refurbishment. SpaceX recovery vessel Bob is named after Demo-2 Astronaut Bob Behnken.
The Psyche Payload
The science satellite was built by Jet Propulsion Laboratory − JPL − on contract by NASA and launched on SpaceX Falcon Heavy FH8 on October 13, 2023 at 10:19:43 EDT.
NASA is sending the spacecraft to an asteroid named Psyche, which orbits the Sun between Mars and Jupiter, to learn how Earth and other rocky planets formed.
This will be the first mission to an asteroid with substantial amounts of metal, as previous missions have explored asteroids made mostly of rock or ice. The asteroid Psyche may be part of the interior of a planetesimal, a building block of a rocky planet. By studying it, scientists seek to determine whether the asteroid was a planetary core.
Attached to the Psyche spacecraft is a technology demonstration, NASA’s Deep Space Optical Communications. This experiment will test the ability of lasers to transmit data at increased rates beyond the Moon.
High-bandwidth optical communications to Earth will be tested during the first two years of the spacecraft’s journey to Psyche. While the optical communications demonstration is hosted by Psyche, its transceiver will not relay Psyche mission data.
The Psyche mission will journey to a unique metal-rich asteroid, also named Psyche, which orbits the Sun between Mars and Jupiter. The asteroid is considered unique, as it appears to largely be made of the exposed nickel-iron core of an early planet – one of the building blocks of our solar system.
NASA Space Operations are unwrapping the Psyche satellite for an inspection. The main parabolic disk is visible and it will keep contact with Earth. The cold gas thrusters are placed in pairs. Source
Deep within rocky, terrestrial planets, including Earth, scientists infer the presence of metallic cores, but these lie unreachable far below the planet’s rocky mantles and crusts. Because we cannot see or measure Earth’s core directly, the mission to Psyche offers a window into the history of collisions and accretion that created terrestrial planets.
NASA’s Launch Services Program at Kennedy Space Center in Florida will manage the SpaceX launch service. The mission is led by Arizona State University. NASA’s Jet Propulsion Laboratory is responsible for the mission’s overall management, system engineering, integration, testing and mission operations.
Maxar Space Solutions is providing a high-power solar electric propulsion spacecraft chassis.The Psyche spacecraft’s nitrogen cold gas thrusters are used to orient the spacecraft in any direction to support the demands of science, power, thermal and other instruments, such as spacecraft orientation and momentum management.
The parameters were recently adjusted in response to updated, warmer temperature predictions for these thrusters. Operating the thrusters within temperature limits is essential to ensure the long-term health of the spacecraft.
Falcon Heavy rocket
SpaceX photo of FH3 STP-2 hanging under the loft cranes in the Horizontal Integration Hangar
Falcon Heavy stands 70 meters tall, weighs about 1.4 million kg at liftoff, and produces a thrust of approximately 22,241 kN from its 27 Merlin 1D engines. The rocket is capable of delivering 63.8 tonnes to low Earth orbit and 26.7 tonnes to geostationary transfer orbit.
Falcon Heavy is a partially reusable heavy-lift launch vehicle designed and manufactured by SpaceX. It is derived from the Falcon 9 vehicle and consists of a strengthened Falcon 9 first stage as the center core with two additional Falcon 9-like first stages as strap-on boosters. Falcon Heavy has the highest payload capacity of any currently operational launch vehicle, and the third-highest capacity of any rocket ever to reach orbit, trailing the Saturn V and Energia.
The combined thrust of the Falcon Heavy 27 Merlin 1D# is 2/3 of the first stage thrust of the five F1 engines on the Saturn V rocket that lifted mankind through the atmosphere on its way to the Moon. This means that Falcon Heavy is almost capable of a Lunar mission like the Apollo Saturn V was. Two launches of Falcon Heavy should be able to do it.
Falcon Heavy consists of a structurally strengthened and therefore heavier Falcon 9 as the "core" component, with two additional Falcon 9 first stages without interstages but with nose cone acting as liquid fuel strap-on boosters, which is conceptually similar to Evolved Expendable Launch Vehicle (EELV) Delta IV Heavy launcher.
The rocket was designed to meet or exceed all current requirements of human rating. The structural safety margins are 40% above flight loads, higher than the 25% margins of other rockets. The Falcon 9 tank walls and domes are made from Aluminium–lithium alloy. SpaceX uses an all-friction stir welded tank. Falcon Heavy was designed from the outset to carry humans into space and it would restore the possibility of flying crewed missions to the Moon or Mars.
The interstage, which connects the upper and lower stage for Falcon 9, is a carbon fiber aluminum core composite structure. Stage separation occurs via reusable separation collets and a pneumatic pusher system. The second stage tank of Falcon 9 is simply a shorter version of the first stage tank and uses most of the same tooling, material, and manufacturing techniques. This approach reduces overall costs during production.
The Falcon Heavy includes first-stage recovery systems, to allow SpaceX to return the first stage boosters to the launch site as well as recover the first stage core following landing at an Autonomous Spaceport Drone Ship barge after completion of primary mission requirements. These systems include four deployable landing legs, which are locked against each first-stage tank core during ascent. Excess propellant reserved for Falcon Heavy first-stage recovery operations will be diverted for use on the primary mission objective, if required, ensuring sufficient performance margins for successful missions.
The nominal payload capacity to a geostationary transfer orbit (GTO) is 8,000 kg (18,000 lb) with recovery of all three first-stage cores versus 26,700 kg (58,900 lb) in expendable mode − They all get expended downrange. The Falcon Heavy can also inject a 16,000 kg (35,000 lb) payload into GTO if only the two boosters are recovered.
The second stage isn’t painted partial gray to prevent the RP-1 from freezing solid during the several hours long transfer trip to its geostationary orbit position. The Sun’s heat will not easily be reflected by the gray paint thus transferring surface heat to the RP-1.
After the deployment there will probably not be enough propellant in the second stage tanks to deorbit. The eight Falcon Heavy second stage will probably be the 35th large piece of space debris that will take eons to deorbit on its own.
2nd stages used on GTO missions usually remain in the highly elliptical transfer orbit with a perigee just a few hundred km above the Earth. The low perigee means it experiences significant drag and the orbit will decay within a year or two, until it reenters.
FH8's second stage current 1.0AU x 2.5AU x 1.1o heliocentric orbit stretches from beyond Earth's orbit past Mars orbit. When reaching Mars the satellite Psyche will accelerate using Mars gravity influence sphere to intercept the asteroid Psyche.
The 2nd stage is with its avionics package in itself a satellite bus, what's missing is solar panels for power supply, gyroscopes for orientation, various military/science instruments and maybe even Hall effect thrusters to perform maneuvers.
SpaceX is the first entity ever that recovers and reflies its fairings. After being jettisoned, the two fairing halves will use cold gas thrusters to orientate themselves as they descend through the atmosphere. Once at a lower altitude, they will deploy drogue chutes and parafoils to help them glide down to a soft landing for recovery.
Lately it’s apparent that the fairings are actively being aiming for the droneship in order to speed up the recovery process and cut corners of the time table. The fairing is actively breaking its speed and turning back before deploying its parachute at the last moment.
Another solution is a ‘vertical’ boost lifting the fairings apogee so the ballistic trajectory is changed aiming for a landing nearer the droneship. It’s equivalent to raising the angle on a water hose giving the water stream an higher arc but giving it a shorter reach.
It’s not clear whether or not the cold gas nitrogen thrusters alone are capable of doing a ‘boost back’ or a ‘push up’ so the fairings can alter their forward momentum mid-flight.
There are three known types of 34 x 17 foot fairings used by SpaceX to protect payload during ascent through the atmosphere. The first type had 10 evenly spaced ventilation ports in a circle on the bottom part of the fairings. This type was not aerodynamic enough to carry a parachute and ACS - Attitude Control System.
The aerodynamic balance during descent must have made them prone to stalling, or they burned up too easily. ACS gas tanks, flight orientation computers and ACS thrusters must have helped with these problems during development of type 2 fairings.
Comparison of Type 1 and 2 with measurements based on pixels - Type 2 are 5-6 inches thicker
The second type is a slightly thicker fairing with only 8 evenly spaced ventilation ports in a circle on the bottom part of the fairings. The ventilation ports release the pressurized Nitrox gas during ascent, but let seawater in which makes it harder to refurbish the fairings after recovery from the ocean.
The new third type has 8 ventilation ports in pair’s near the edge of the fairings. Some old type 2 fairings have been rebuilt and reused in Starlink launches. That have been a test program to develop the type 3 fairings to prevent saltwater from the ocean from flooding and sinking the fairing, and makes refurbishment toward the next flight easier.
Falcon fairings halfs have been recovered and reused since 2019. Improved design changes and overall refurbishment procedures have decreased the effects of water landings and led to an increased recovery rate of fairings.
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