Design status of the Mobile Asteroid Surface Scout (MASCOT)
for the Hayabusa-2 mission
J. Biele, S. Ulamec, Caroline Lange, Christian Krause, Tra-Mi Ho, Susanne Wagenbach, Lars Witte, Eugen Ksenik, Tim van Zoest and the MASCOT-Study Team
(4) System Requirements and Baseline Design
(1) Background
(1) MASCOT = “Mobile Asteroid Surface Scout“, strong
heritage from PHILAE (Rosetta Lander, launched
2004)
(2) Mobility by „hopping“ in µ-gravity
(3) Several proposals for asteroid missions (ESA’s Marco
Polo, Marco Polo R, JAXA’s Hayabusa-2 identified
interest in a dedicated lander for in-situ science  DLR
Bremen proposed MASCOT as a dedicated lander
(4) JAXA/ISAS: to launch Hayabusa-2
primary flight opportunity
• Mission: Launch 2014/15; Deployment June-August 2019, release alt. 100m
April 2019
south pole
iluminated
Aug. 2019
equinox
impact of penetrator (TBD)
HAYABUSA-2 sampling
dress rehearsals,
MASCOT deployment
June 2018 /
Sep. 2019
perihelion
HAYABUSA-2
arrival
90
Jan. 2019
apohelion
1999 JU3 orbit
in 2014/15 
(5) MASCOT now in Phase B, breadboards being built
Feb. 2019
global
characterization
completed
July 2018 / Nov. 2019
north pole iluminated
Nov. 2018
equinox
Aug. 2018 /
Dec. 2019 HAYABUSA-2
departure
(6) Adaptable to other missions to small bodies
[JAXA/ISAS]
[ESA]]
[JAXA/ISAS]
Fig.: Hayabusa-2 and MASCOT Mission Timeline
Fig.: Artists rendition of Marco Polo (left) and Hayabusa at ITOKAWA (middle and right)
(3) Target Body
• Mission duration: 16 hrs of on-asteroid operation
• Main functions:
• On-surface up-righting and mobility (incl. attitude determination) by internal torquer
• Mainly autonomous science measurements and operation without ground
interference
altitude
Home Position
20 km
1999 JU3
• C-type asteroid is likely to be a rubble-pile
• size of 1999 JU3 comparable to ITOKAWA
Fig.: Views of ITOKAWA (left) and
size comparision (bottom)
Deployment
Altitude
100 m
D Daytime Measurements
N Nighttime Measurements
Relocation
Up-Righting
SDL-Phase
On-Surface Operation
1 asteroid day
1st Science Cycle
D
N
N
D 2nd Science Cycle
Fig.: MASCOT On-Surface Operations
Abe, M., Kawakami, K., Hasegawa, S.
et al. 2008, COSPAR Scientific
Assembly, B04-0061-08.
Kawakami, K. 2009, Master's thesis,
University of Tokyo
Fig.: 1999 JU3 shape model and gravitational model
(2) Science Objectives
MASCOT was proposed to fill the gap between remote
investigations by the main-S/C and investigation of
returned samples
Remote:
• GLOBAL study of the target body
• Link to telescopic data
• Sampling site selection
Returned Samples:
• MICROSCOPIC study of the target body
• Link to meteorite/cosmic dust collection data
• Can use the most updated analytical facilities at
return
MASCOT:
• LOCAL study of the target body
• Cross-scale link between mother-S/C data and
sample analyses
• Sampling site investigation in-situ, analytical
capabilities
• Direct exploration of sub-surface information
(3) Payload (for MASCOT on H-2)
•
•
•
•
Wide Angle Camera to CAM (0.4 kg)
obtain multispectral images of the landing
site and provide geological context for
MASCOT PL
MicrOmega to imaging spectrometer (1,9
kg) to determine mineralogical
composition and characterize grains size
and structure of surface soil samples at μscale
Mid-IR thermal sensor Mara (0.12 kg) to
map NEA‘s surface temperature to
determine the thermal inertia 
Yarkovsky, YORP
3-axis fluxgate Magnetometer MAG
(0.15 kg) to determine magnetization of
the NEA  formation history
µOmega
MAG
• Payload: 4 instruments with 3 kg total mass including margins
• Configuration: Prismatic body with fixed instrument accommodation
• Structure: no boxes, but integrated structure (including common electronics
accommodation)
Figs.: MASCOT Design
• Highly integrated approach for all
subsystems, passive and low risk
system
• Thermal: mainly passive (i.e. using
coatings and MLI) with heating only
during cruise and for warm-up
• Communication: UHF-band using
synergies with the main-S/C
• Power:
Primary
battery
only,
210 Wh (LiSOCl2)
• Redundancy for onboard computer
• High degree of autonomy
• Long-lived version about same
mass
Fig.: MASCOT after eject from H-2
(MESS interface)
Tab. 1: Mass Budget
Contact
CAM
MARA
Jens Biele German Aerospace Center / DLR RB-MUSC
Linder Höhe 1, 51147 Köln / GERMANY
Telefone: +49-2203-601-4563; E-Mail: jens.biele@dlr.de
International Primitive Body Exploration Working Group 2011 Workshop