EGU General Assembly 2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.

Interstellar Probe: Pushing the Frontier of Space Science

Pontus Brandt1, Kathleen Mandt1, Elena Provoronikova1, Casey Lisse1, Kirby Runyon1, Abigail Rymer1, Ralph McNutt1, Michael Paul1, and the The Interstellar Probe Study Team*
Pontus Brandt et al.
  • 1The Johns Hopkins University Applied Physics Laboratory, SRP, Laurel, United States of America (
  • *A full list of authors appears at the end of the abstract

An Interstellar Probe beyond our heliosphere in to the largely unexplored interstellar medium (ISM) would be the furthest and boldest step in robotic space exploration ever taken. A dedicated payload of in-situ and remote sensing instruments would uncover the new regime of physics at work in the heliospheric boundary region and offer the first external view of the global heliosphere that is currently missing in the family portrait of all other types of astrospheres observed. Beyond about 400 AU the Probe would reach the ISM and for the first time begin its sampling of the properties of the local interstellar cloud (LIC) that our Sun and neighboring star systems are immersed in.

An Interstellar Probe has been discussed since around 1960 in several NASA and international studies. The compelling science objectives have remained almost unchanged and are focused on understanding the plasma physics in the interaction region between the heliosphere and the ISM. Their importance have been amplified by the recent unexpected findings by the Voyager 1 and 2 spacecraft that are nearing their end of life at less than 150 AU from the Sun. Remote observations in Energetic Neutral Atoms (ENAs) by the NASA IBEX and Cassini missions have made the remarkable discoveries of ENA emission morphologies that have come as a complete surprise and still lack a satisfactory explanation. Hubble Space Telescope observations have now also made it clearer that the Sun is about to exit the LIC and perhaps already has, which is a unique event of astronomical scales that an Interstellar Probe could explore in-situ for the first time. In addition to these top-priority objectives, contributions of unprecedented science value to planetary sciences and astrophysics are possible including flybys of at least one Kuiper Belt Object, in-situ and remote observations of the dust debris disk, and the extra-galactic background light.

Here we review the outstanding questions and current state of understanding of the global heliosphere, the ISM and what planetary and astrophysics augmentations can offer. We summarize the compelling science case for an Interstellar Probe, including a range of possible science payloads and the associated operation scenarios. The results stem from the study of a Pragmatic Interstellar Probe currently underway, funded by NASA, and led by The Johns Hopkins University Applied Physics Laboratory with active participation from a large, international team of scientists and engineers. The study focuses on finding realistic mission architectures among a trade space of propulsion options, trajectories, risks and reliability challenges. The study considers operation out to 1000 AU, a survival probability of 85% over 50 years and electrical power of no less than 400 W at the beginning of mission. Over twice the speed of Voyager 1 (the fastest spacecraft currently) has already been achieved in the design using conventional propulsion, with a direct inject to Jupiter followed by a Jupiter Gravity Assist. In order to provide input requirements to the mission study, several possible payloads with different mass allocations and associated mission requirements, trade-offs and risks have been identified.

The Interstellar Probe Study Team:

Ahrens,Caitlin Alexashov,D. Alkalai,Leon Allegrini,Frederic Alterman,Ben Altobelli,Nicolas Alvarez,Erika Arnhof,Marlies Arnold,Steve Bailey,Elizabeth Baker,Daniel Bale,Stuart Baliukin,Igor Balogh,Andrew Bannister,Michelle Barabash,Stas Baranov,V. Batygin,Konstantin Bavassano,B. Beddingfield,Chloe Beichman,Charles Benecchi,Susan Benz,Willy Bergman,Jan Bert,Chris Bertaux,Jean-Loup Billings,Lee Blackwood,Gary Blanc,Michel Bock,Jamie Boschler,Peter Bougeret,Jean-Louis Bramanti,Cristina Brandt,Pontus Breitschwerdt, Brown,"Michael, Mike" Bruno,Roberto Burger,Adri Bzowski,Maciej Bzowski,Macek Cairns,Iver Casolino,Marco Cecconi,Baptiste Chalov,S. Chen,Christine Cheng,Andy Christian,Eric Clarke,John Cocoros,Alice Cohen,Christina Cooper,John Cooray,Asantha Coustenis,Athena Crary,Frank Creech,Stephen Curry,Shannon Czechowski,Andrzej Dalle Ore,Cristina Daly,Terik Dandouras,Iannis Decker,Rob Deleuil,Magali DelloRusso,Neil DeMajistre,Bob Derleth,Jason Desai,Mihir Domogal-Goldman,Shawn Dr. Ferreira, Dr. Alycia J. Weinberger, Draine,Bruce Droege,Wolfgang Dyson,Freeman Earle,Alissa Elliott,Heather Eriksson,Stefan Fahr,Hans Fast, Fichtner,Horst Fisk,Len Forsyth,R. Friedman,Louis Frisch,Priscilla Fujimoto,Masaki Funsten,Herbert Fuselier,Stephen Geiss,Johannes Genovese,Angelo Gerrish,Harold Gkioulidou,Matina Gladstone,Randy Glassmeier,Karl-Heinz Glocer,Alex Gloeckler,George Goldman,Shawn Greaves,Jane Greene,Jim Grundy,Will Gruntman,Mike Gulkis,Samuel Gurnett,Donald Hakimzadeh,Roshanak Hansteen,Viggo Harman,Sonny Hartman,Colleen Hayes,Jeff Heber,Bernd Higginson,Aleida Hill,Patrick Hill,Matthew Hillebrand,Lynn Ho,George Hofstadter,Mark Holler,Bryan Horanyi, Horanyi,Mihaly Horbury,T. Ip,Wing-Huen Izenberg,Noam Izmodenov,Vlad Janhunen,Pekka Johnson,Les Johnson,Lonnie Johnson,Perianne Kalirai,Jason Katushkina,Olga Keane,James Kezerashvili,Roman Kinnison,Jim Klecker,Berndt Kocharov,Leon Koehn,Patrick Kollmann,Peter Korreck,Kelly Kowalska-Leszczyńska,Izabela Krimigis,Tom Kunow,H. Kurth,William Kyrola,Erkki Lallement,Rosine Lammer,Helmut Lanzerotti,Louis Lavraud,Benoit Lee,Marty Lee,Gentry Leipold,Manfred Leisner, Leroux,Jakobus Levinson,Hal Li,Hui Lie-Svendsen,Oystein Liewer,Paulett Linsky,Jeff Lisse,Carey Livi,Stefano Lloyd,James Loeb,Avi Long,Kelvin Lubin,Philip Malhotra,Renu Mall,U. Mamajek,Eric Mandt,Kathleen Mann,Ian Mannheim,K. Marsch,E. Marsden,Richard Maruca,Bennett Mastandrea,James Mather,John Matloff,Gregory Mazur,Joseph McComas,David McKinnon,Bill McNutt,Ralph Melin,Henrik Merkin,Viacheslav Mewaldt,Richard Miles,David Millis,Marc Mitchell,Donald Moebius,Eberhard Moore,Jeff Morbedelli,Allessandro Mostafavi,Parisa Mousis,Olivier Murchie,Scott Napolillo,David New,Michael Nikoukar,Romina Noll,Keith Ogasawara,Keiichi Ogasawara, Opher,Merav Ord,Kim Park,Jeewoo Parker,Alex Paschalidis,Nikolaos Paty,Carol Paul,Michael Paxton,Larry Perrin,Mike Poppe,Andrew Porter,Simon Posner,Arik Protopapa,Silvia Provornikova,Elena Quemerais,Eric Quick,Lynnae Rahman,Ashique Rankin,Jamie Raouafi,Nour Rataj,Miroslaw Ratkiewicz,Romana Redfield,Seth Reed, Retherford,Kurt Richardson,John Rivkin,Andy Roberge,Aki Roelof,Ed Rogers,Gabe Runyon,Kirby Rymer,Abigail Ryschkewitsch,Mike Scherer,Klaus Schlei,Wayne Schmidt,Walter Schwadron, Schwieterman,Eddie Seager,Sara Short,Kendra Sigurdsson ,Steinn Silva,Clara Simon,Margaret Singer,Kelsi Slavin,James Slavin ,Jonathan Smith,David Smith,Joe Smith,Todd Smith,David Smith,Clayton Sorriso-Valvo,Luca Sotzen,Kristin Spilker,Linda Spitzer,Sarah Srama,Ralf Sreenivasan,Ranga St. Cyr,Chris Stansberry,john Stapplefeld,Karl Stark,Chris Sterken,Veerle Stern,Alan Stevenson,Kevin Stone,Edward Stough,Robert Strumik,Marek Summerer,Leopold Szabo,Adam Szalay,Jamey Torsti,Jarmo Trattner,Karl-Heinz Tucker,"Orenthal, O.J." Turyshev,Slava Ukhorskiy,Sasha Umurhan,Orkan Valtonen,Eino Velli,Marco Vernon,Steven Vertesi,Janet VonSteiger,Rudolf Wagner, Wahlund,Jan-Erik Wang,Linghua Wang,Chi Weaver,Harold Werner,Michael Westlake,Joseph White,Oliver Wicks,Robert Willems,Phil Wimmer-Schweingruber,Robert Witte,Mannfred Woch,Joachim Wood,Brian Wuerl,Adam Wurz,Peter Wyatt,Mark Yermolaev,Y. Young,Leslie Zank,Gary Zarka,Philippe Zelenyi,Lev Zemcov,Michael Zide,Alan Zimbardo,G. Zong,Q.

How to cite: Brandt, P., Mandt, K., Provoronikova, E., Lisse, C., Runyon, K., Rymer, A., McNutt, R., and Paul, M. and the The Interstellar Probe Study Team: Interstellar Probe: Pushing the Frontier of Space Science, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19605,, 2020

Display materials

Display file