JUMPER: JUpiter MagnetosPheric boundary ExploreR

R. W. Ebert1, F. Allegrini1, F. Bagenal2, C. Beebe1, M. A. Dayeh1, M. I. 

Desai1, D. E George1, J. Hanley1, P. Mokashi1, N. Murphy3, P. W. Valek1, 

D. Wenkert3, A. Wolf3, C.-W. L. Yen3

1SwRI, 2CU/LASP, 3NASA/JPL

Planetary Science Deep Space SmallSat Studies

Sunday March 18, 2018
• A Jupiter orbiting SmallSat mission concept.

• It rides to Jupiter on a primary spacecraft.

• Science focuses on Jupiter’s magnetosphere.

• Spacecraft details.

• ESPA-class.

• Solar powered.

• Direct-to-Earth (DTE) communications.

• Hydrazine propulsion.

• Final report delivered to NASA on 12/29/17. 

• 7 month project.

What is JUMPER?

A representation of the 

desired orbit for JUMPER. 
JUMPER focuses on two science topics:

1. The solar wind’s impact on Jupiter’s magnetosphere.

2. Mass and energy transport through Jupiter’s magnetosphere.

Jupiter’s Magnetosphere
How does the solar wind (SW) influence the configuration 

and dynamics of Jupiter’s magnetosphere? 

Science Question #1

Processes with evidence of SW influence

-Motion of Jupiter’s bow shock and 

magnetopause.

-Opening and closing of magnetic flux at 

the magnetopause.

- Transport of mass & energy into the 

magnetosphere.

-Variations in UV aurora brightness and 

morphology.

- Radio emission enhancements.

- Current sheet asymmetries in 

magnetotail.
How does the SW interact with Jupiter’s magnetopause? 

Delamere & Bagenal 2010 Ebert et al. 2017

Science Question #2
What are the flux and energy spectra of energetic neutral 

atoms (ENAs) escaping Jupiter’s magnetosphere? 

Mauk et al. 2004

Mauk et al. 

2004

Mitchell et al. 

2004

Science Question #3
Instrument Ion and Electron

Sensor (IES)

Magnetometer (MAG) Neutral Atom Imager 

(NAI)

Baseline

Design

Electrostatic Analyzer + 

Detector

Vector Helium 

Magnetometer

Single Pixel Imager

Operating 

Range/Resolution

4.3 eV/q – 17.6 keV/q

ΔE/E: ~8%

± 1000 nT

<20pT/√Hz at 1Hz

~0.5 – 10 keV

ΔE/E: ~50% 

Field-of-view 90° x 270° 3-axis 6.5° x 6.5°

Time Resolution 128s 1 - 60s 600s

Mass 2.2 kg ~0.74 kg 9.4 kg

Power 1.85 W ~ 3.6 W ~6 W

Heritage Rosetta/IES INSPIRE, CuSP, 

Europa/ICEMAG

TWINS, IBEX-Hi, IMAGE/

MENA, Cassini/INCA

JUMPER targets high heritage science instruments.

Science Payload
• JUMPER launches with primary 

vehicle.

• JUMPER’s interplanetary cruise is 

expected to last 2.5 years.

• Assuming ride w/ primary vehicle 

+ SLS Launch) 

• Primary spacecraft + JUMPER 

arrive at Jupiter.

• JUMPER rides with primary 

spacecraft through Jupiter orbit 

insertion (JOI). 

Mission Design

JUMPER Interplanetary Cruise
Mission Design
Mission Design
Spacecraft

Key Performance Characteristics

ESPA-Class Limits

Mass: 180 kg; 

Volume: 61 cm x 71.1 cm x 96.5 cm
- All communication is DTE (Navigation, Data Downlink & Uplink).

- The CDS consists of 

- IRIS Deep-Space Transponder.

- Solid-state power amplifiers

- Transmit antennas (x4).

- Low noise amplifiers.

- Receive antennas.

- Link budget analysis:

- 2 kbps with >3 dB margin using 12 W of transmission power (34 m DSN)

- 8 kbps can be achieved with the 70 m DSN.

Commun. & Data System
JUMPER hydrazine propulsion 

system (from Moog, Inc.)

- Orbit adjustments are made using a 

a monopropellant (hydrazine) blowdown

thruster system (Moog, inc).

- Total propellant mass is 22 kg.

- 336 m/s of ΔV for the mission.

Hydrazine Propulsion System
The EPS is build around a battery backed main 28V bus and consists of: 

Solar Arrays

- 12 (4 x triple deployed solar panels).

- 1944 cells at 29.5% efficiency

A peak-power tracker (PPT)

- 94% efficiency; supplies 60 W BOL (45 W EOL) 

to main 28V bus.

Low-voltage power supply (LVPS)

- Regulates low voltages for use by the SATYR single 

board computer & PPT. 

Batteries

- 640 Whr. of primary and secondary battery capacity.

Electrical Power System 
Flight Avionics Subsystems

SATYR Single Board Computer (SBC)

- Performs all on board processing.

- 4 GB of flash memory

Flight Software (FSW)

- Re-use of CYGNSS and CuSP FSW 

wherever possible.

Attitude Determination and 

Control System

- Uses COTS components.

- Star trackers are used for pointing.

- Magnetorquers to de-saturate reaction wheels.
Primary Spacecraft Accommodation
Launch Vehicle Interface
Separation Profile
Summary

- JUMPER is a Jupiter orbiting SmallSat mission concept to study (i) 

the solar wind’s influence on and (ii) the contribution from ENAs to 

mass loss from Jupiter’s magnetosphere.

- It rides to Jupiter with a primary spacecraft and uses a series of 

Ganymede and Callisto flybys to achieve its desired orbit.

- It has undergone a mission concept study through NASA’s PSDS3 

program.

- Mission details can be found in 2018 IEEE Aerospace Conference publication.

- This mission concept is applicable to other planetary systems.
Science Questions Mission Design

1. How does the solar wind (SW) influence the 

configuration and dynamics of Jupiter’s 

magnetosphere?

1. How does the SW interact with Jupiter’s 

magnetopause?

1. What are the flux and energy spectra of energetic 

neutral atoms escaping from Jupiter’s 

magnetosphere?

Spacecraft Key Performance Characteristics

Mission Summary