1Ingo Gerth – Presentation at IGSS, Beihang University

MUSEMISSION TO THE

URANIAN SYSTEM

2Ingo Gerth – Presentation at IGSS, Beihang University

OUTLINE

1. Science case2. Architectural trades3. Spacecraft design4. Critical issues

3Ingo Gerth – Presentation at IGSS, Beihang University

MISSION STATEMENT

MUSE will explore the Uranian system• as an archetype for ice giants;• to give crucial answers about its current state and

evolution, and that of the solar system;• using an orbiter and a probe by 2044.

4Ingo Gerth – Presentation at IGSS, Beihang University

WHAT DO WE KNOW ABOUT URANUS?

• Voyager 2 fly-by in 1986– Ru = 14.5 Re

– Rotational period 17 hrs– 27 known satellites, 5 moons– Orbital period 84 years– 11 rings

• Largely unexplored

5Ingo Gerth – Presentation at IGSS, Beihang University

ROTATIONAL CONFIGURATION

Ecliptic

Rotation

B-Field

6Ingo Gerth – Presentation at IGSS, Beihang University

FIELDS OF STUDY

InteriorAtmosphere MagnetosphereMoons & rings

7Ingo Gerth – Presentation at IGSS, Beihang University

FIELDS OF STUDY

Rotation rateGravity field

Radio tracking Radiooccultation

Magnetometer

Camera

Size & shape Radius Electromagneticattenuation

Radio plasmawave package

ELF antenna

InteriorAtmosphere MagnetosphereMoons & rings

8Ingo Gerth – Presentation at IGSS, Beihang University

CONCEPTS

1.

2.

3.

4.

5.

6.

mp [kg] Probes Sub-sats Moon tour?

50 2 ✘ ✘

100 1 ✘ ✘

100 1 ✘ ✔

150 1 ✘ ✘

100 1 1 ✘

100 ✘ 1 ✔

9Ingo Gerth – Presentation at IGSS, Beihang University

TRADE-OFF

0%

20%

40%

60%

80%

100%

120%

140%

160%

100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0%

Nor

mal

ized

sco

re

Engineering weight

Flyby Small orb, / 2 probesOrbiter w/ probe and moons Orbiter w/ probeOrbiter, slave and moons Orbiter, slave and probe

10Ingo Gerth – Presentation at IGSS, Beihang University

TRADE-OFF

0%

20%

40%

60%

80%

100%

120%

140%

160%

100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0%

Nor

mal

ized

sco

re

Engineering weight

Flyby Small orb, / 2 probesOrbiter w/ probe and moons Orbiter w/ probeOrbiter, slave and moons Orbiter, slave and probe

MUSE CANDIDATE: Probe + Moon Tour

11Ingo Gerth – Presentation at IGSS, Beihang University

TRANSFER – INNER SOLAR SYSTEM

Earth GAs

Venus GA

LaunchSep. 26, 2026C3 = 12.4 km2/s2

M = 2553 kgAriane 5 ECA

12Ingo Gerth – Presentation at IGSS, Beihang University

OUTER SOLAR SYSTEM

Jupiter GA

Orbit insertionFebruary 2044TOF = 26 years∆Vtot = 2.16 km/s

Probe releaseNovember 2043

13Ingo Gerth – Presentation at IGSS, Beihang University

ARRIVAL AT URANUS

Orbiter

Probe

14Ingo Gerth – Presentation at IGSS, Beihang University

SCIENCE PHASESS

cie

nce

Ph

ase

1 -

US

O

Scie

nce

Ph

ase

2 -

MT

OPolar

60 Ru

15Ingo Gerth – Presentation at IGSS, Beihang University

SPACECRAFT DESIGN

4 ASRGs – 5 m antennta/7 kbps (20 AU) – 500 N bi-prop engine3-axis stabilised – 150 kg entry probe

16Ingo Gerth – Presentation at IGSS, Beihang University

SYSTEM BUDGETS

4,67,3

54,9

14,6

14,8

3,8% of total

Payload Launcher adapter Bus Probe System margin Excess

Item Mass w/ margin [kg]

Dry mass 2052

Propellant mass 2167

Launch mass 4219

AR 5 performance 4300

Excess capacity 81 (2%)

Electrical Power Subsystem

Source 4 ASRGs

P @ BOL 436 W

Peak power 361 W

Li batteries 40 kg/3374 Wh

ASRG failure 2786 Wh required

17Ingo Gerth – Presentation at IGSS, Beihang University

DESIGN DRIVERS

• Earth ↔ Uranus distance: 20 AU– Low solar flux: Radioactive power source– Low data rate

• Thermal discrepancy: Uranus ↔ Venus fly-by– Antenna as heat-shield

• Long mission duration– Extreme reliability requirements

18Ingo Gerth – Presentation at IGSS, Beihang University

CRITICAL ISSUES

• ASRG availability & launcher compatibility• System lifetime and qualification• Jupiter fly-by radiation environment• Cost: B€ 2.3, rough order of magnitude• Descoping options– Satellite tour– Fly-by instead of orbiter– Probe is a must

19Ingo Gerth – Presentation at IGSS, Beihang University

NEXT STEPS

• Contribution toUranus Pathfinder(Arridge et. al.)

• ESA L-Class proposed• Further consolidation• Collaboration!

20Ingo Gerth – Presentation at IGSS, Beihang University

SUMMARY

• First dedicated mission to study an icy giant– Improve understanding of Solar System formation

and exoplanets– Expand knowledge of Uranian system

• Detailed trade study to generate optimality envelope– Orbiter with probe and satellite tour selected

21Ingo Gerth – Presentation at IGSS, Beihang University

CREDITS

T. Bocanegra, C. Bracken, M. Costa, D. Dirkx, I. Gerth, K. Konstantinidis, C. Labrianidis, M. Laneuville, A. Luntzer, J. MacArthur, A. Maier, A. Morschhauser, T. Nordheim,

R. Sallantin, R. Tlustos

Supported by…

C. Arridge, T. Denk, C. Erd, P. Falkner, M. Hallmann, G. Kargl, M. Voller, and many others

22Ingo Gerth – Presentation at IGSS, Beihang University

MUSEMISSION TO THE

URANIAN SYSTEM