Escapade Aircraft

Escape and Plasma Acceleration and Dynamics Explorers (EscaPADE) is a planned spacecraft mission to Mars consisting of two spacecraft known as ''Blue'' and ''Gold''. The mission, expected to launch in August 2024, is part of NASA's SIMPLEx program.

Mission

EscaPADE is led by Principal Investigator Dr. Robert Lillis and colleagues at the University of California, Berkeley. At a cost of US$79 million (including launch vehicle), the mission will demonstrate low cost planetary space exploration. The twin spacecraft will study Mars' unique magnetosphere and how solar wind contributed to the loss of most of the planet's atmosphere over solar system history. In February 2023, Blue Origin won a contract to launch the mission in 2024.

Instruments and science goals

The science goals of EscaPADE are to:
* understand the processes controlling the structure of Mars' hybrid magnetosphere and how it guides ion flows;
* understand how energy and momentum are transported from the solar wind through Mars' magnetosphere;
* understand the processes controlling the flow of energy and matter into and out of the collisional atmosphere.

Each identical EscaPADE spacecraft has a dry mass of ~200 kg, with a wet mass of <550 kg. The spacecraft bus is originally adapted from the Rocket Lab Photon third stage and is approximately 60 x 70 x 90 cm. The spacecraft is powered by two 480 x 70 cm solar array wings. Chemical propulsion is provided by thrusters from ArianeSpace. Reaction wheels, inertial measurement units, and star trackers are used to maintain orientation, with cold gas thrusters to desaturate the wheels. Communications are in X-band via a 60 cm diameter dish antenna. A 200 cm boom extends above the spacecraft, hosting the EMAG and ELP mNLP sensors.

There are three science experiments onboard each identical spacecraft, EMAG, EESA, and ELP. EMAG is a magnetometer that will measure DC magnetic fields up to 1000 nT, mounted at the end of the boom to reduce magnetic noise from the spacecraft. EESA is an electrostatic analyzer designed to measure the energies, fluxes, and masses of suprathermal ions from 2 eV to 20 keV and energies and fluxes of suprathermal electrons from 3 eV to 10 keV. It is mounted on the upper deck of the spacecraft bus, with a 240° x 120° field of view for electrons and 247.5° x 90° field of view for ions. ELP is a Langmuir probe, consisting of three separate sensors: the multi-needle Langmuir probe (mNLP) consists of 4 thin needles mounted in two pairs ~3/4 way up the boom and measures thermal electron density; the two planar ion probes (PIPs) are mounted on the instrument deck and measure thermal ion density, and the floating potential probe (FPP) is also mounted on the spacecraft deck, and measures changes in relative spacecraft electrostatic potential.

After launch, EscaPADE spend approximately six weeks in Earth orbit before executing a trans-Mars injection (TMI) in October 2024. The twin probes will reach Mars in September 2025 and go into a highly elliptical orbit. Over the following six months the orbit will be lowered and circularized until it reaches the nominal science orbit. Science Campaign A involves both spacecraft flying in the same orbit at varying distance from one another, ~170 x 8400 km (5.66 hours) with an inclination of 65 degrees. This will last approximately 6 months, at which time Blue will lower its apoapsis to 7000 km and Gold will raise its apoapsis to 10,000 km. With different orbital periods (4.9 and 6.6 hours), the orbits will precess (due to Mars' nonuniform gravity field) at different rates, and thus separate, allowing simultaneous measurements of distant parts of the Mars magnetosphere. This campaign will operate for approximately 5 months, until the end of the nominal science mission in early March 2027.

Further reading

ESCAPADE: A TWIN-SPACECRAFT SIMPLEX MISSION TO UNVEIL MARS’ UNIQUE HYBRID MAGNETOSPHERE

References

NASA space probes
Missions to Mars
2024 in spaceflight
{{Mars-stub