Project Icarus Design Steps Up A Gear

Dear Friends,

We are pleased to inform you about progress on the Project Icarus interstellar starship design study, the collaboration between the British Interplanetary Society and the non-profit organisation Icarus Interstellar, Inc. Project Icarus was founded by Kelvin F. Long and Richard Obousy and launched back in September 2009 during a symposium at the BIS HQ in London.  The goal set was to redesign the 1970s BIS Project Daedalus spacecraft.

Since 2009 we have been through several phases under a rotating team management where the project leaders have been Kelvin Long, Richard Obousy, Andreas Tziolas and Pat Galea; the current project leader is Rob Swinney. Each one of these people has brought their own passion and unique style to the project, attempting to juggle difficult design issues while managing an international volunteer team.

Most of the work to date has been focused on research and the team has performed dozens of internal studies, written many internal reports, and published papers in journals such as the JBIS and Acta Astronautica. The team has examined propulsion issues, structural engineering, fuel acquisition, communications, reliability, science payload designs, and issues relating to SETI among other topics. This has all helped to facilitate one of the goals of Project Icarus: training up a new generation able to apply analytical skills to the hard engineering and physics problems associated with interstellar flight. The team have also performed extensive reviews of the original Daedalus design, validating many aspects but highlighting some that were in need of revision in the light of developments in technology and science.

The team made exceptional progress in understanding the variety of problems associated with interstellar flight, but progress on the actual design had been slower than hoped. Specifically, they had come up with various concepts for what the Project Icarus vehicle might look like, but at the time these were just ideas. One stumbling block had been the variety of fusion propulsion systems to choose from given the Project Icarus requirement to keep the system mainly fusion based, like Daedalus. The team counted no less than 20 ways of doing fusion propulsion and selecting the preferred one was not an easy task.  As a consequence the team were caught in a loop for some time; with differing opinions on what sort of propulsion system would be most appropriate for Project Icarus.

In an attempt to get out of this loop, and under the supervision of then Project Leader Pat Galea, the team went through the exercise of revisiting the original Terms of Reference (ToR) for the project released in 2010 (Long, et al, Project Icarus: Son of Daedalus – Flying Closer to Another Star, JBIS, 62, 11/12, pp.403-414, November/December 2009).  Following the first several years of research, the fresh look led to a sensible tweaking of the project ToR and further led to the creation of a set of higher level systems engineering requirements (see appendix).

Nonetheless, in an ideal world the team might produce a hundred different design configurations with variations on the propulsion type, fuels, deceleration mechanisms, and mission profile. This would allow a full scoping of the design space, informing the designers of the realistic engineering solutions. However, team resources were limited. In particular, as a volunteer group, available time was limited. So an alternative approach had to be found. 

Recently, Rob Swinney took over as the fifth project leader, and one of the activities he initiated was an internal design competition running from March to October 2013. The motivation for this competition was to catalyse further technical progress in the team whilst providing a step change in the decision process. The team divided themselves into several sub-teams with the aim of each designing a full concept vehicle configuration with significantly distinguishing characteristics (so as to separate the design solution options) and with an added twist – the sub-teams would be mostly blind to each other’s work during the internal competition process. This was to minimise influence over ideas, encourage innovative thinking, and to provide a friendly competitive element to galvanise some progress.  In this way if the designs were sufficiently different and developed to a high level, then the team as a whole could use this information to inform judgements on what the preferred design modes were for the mission, e.g., “If you do it this way, this is what it would take”.  The teams have now been hard at work for the last several months and are:


Concept Design Team A: Kelvin Long’s team includes Richard Osborne and Pat Galea.  The team is known as the Starship Resolution team and are looking at shock ignition ICF-based propulsion that utilises a combination of D/D and D/He3 fuel and will be effecting full deceleration of a 150 ton payload into the target system. The team is also looking at the adoption of a Medusa sail system to augment the deceleration burn.


Concept Design Team B: Milos Stanic is leading the ‘UltraD’ team doing a pulsed-pellet system with single-laser ignition of ultra-dense deuterium cores.  They consider that with the extreme density, a pellet of UDD could be ignited with a single 10 PW laser shot. Otherwise the team are starting with a top-down approach, specifying the mission envelope, and then iteratively building down to the necessary engine performance.  Milos is being assisted by Richard Hatcher and Mitchell Rodriguez.


Concept Design Team C: The ‘Z-pinch’ Team is led by Robert Freeland and supported by Stephen Baxter, Richard Obousy and Sett You. They are planning a Z-pinch scheme with LiD fuel and mag-sail augmented deceleration.


Concept Design Team D: A Plasma Jet Magnetic Inertial Fusion (PJMIF) variant known as the Icarus ‘Mark Series’ design team is led by Andreas Tziolas and includes the team members Haym Benaroya, Dimos Homatas, Andy Karam, Phillip Reiss, Adrian Mann, Divya Shankar, Tiffany Frierson, Kostas Konstantinidis, and Frederik Ceyssens. The team is supported by Jason Cassibry from the design consultants team (see below) for specific help on the propulsion system definition and requirements.


Concept Design Team E: Andreas Hein was a late entrant and is leading a student team mainly based at Munich University including Christian Buhler, Martin Langer, Nikolas Perakis, and Lukas Schrenk amongst others.  They have chosen a D/T fast ignition fusion propulsion scheme.


All the design teams will be able to call on the experience and support of other members of the Project and in particular a group known as the Concept Design Competition Consultants Team; Rob Adams, Adam Crowl, Jim French, Rod Smith, Brian Bixler and Jason Cassibry.  Adam Crowl is also the Primary Propulsion Module Leader for Project Icarus and with the consultants team will be monitoring the fusion propulsion trade space not covered by the design teams as part of an overall propulsion review.

The precise evaluation criteria were discussed and agreed upon by the Project Icarus Core Design Team although the criteria may still be further refined in agreement with the concept design team leaders. In the first instance the designs will be evaluated in how well they are judged to be able to meet the revised ToRs and other requirements.  But the design teams will be expected to carefully present the physics that support their scheme, and they will be expected to show how the engineering implementation is ‘demonstrated’ to an appropriate level for a concept design that is perhaps just an iteration away from being submitted for review as the Project Icarus Preliminary Design. If there was any doubt about the design methodology, the teams were to keep in mind the original Project Programme Document, which included instructions such as different design philosophies. Each team is expected to produce a concept design report aimed for publication in JBIS.  Engineering drawings will be drafted and rendered by the project team’s artist, Adrian Mann, to help visualise each of the machines.

Over 21st and 22nd October 2013, members of the Project Icarus Study Group will assemble at the BIS HQ in London. At this event the teams will take part in both private and public workshops and the preferred design will be announced. This should prove for an exciting event. It is likely however that the eventual Project Icarus design will be some combination of all of these design solutions, taking the best elements of each in order to produce a more optimised design for a starship which can take the original Project Daedalus study to the next level. Whatever the outcome, it is interesting to note that the Project Icarus Study Group will effectively be developing several design concepts for an interstellar probe. This takes us one step nearer to achieving this difficult ambition as we continue to reach for those distant worlds.

The Project Icarus Study Group, June 2013



Project Icarus will be well represented at the Icarus Interstellar Starship Congress, their first ever international assemblage of recognised interstellar space proponents, taking place at the Anatole Hilton in Dallas Texas, August 15-18th.

The Starship Congress will host interstellar organizations and distinguished speakers of the interstellar community. Registration is now open on the Icarus Interstellar website




The revised ToR is as follows:


  1. Project Icarus will build on the work of Project Daedalus, and will produce a design for an unmanned probe that is capable of delivering useful scientific data about the target star, associated planetary bodies, stellar environment, and the interstellar medium.
  2. The spacecraft will use current or near-future technology, and should be capable of being launched as soon as is credibly determined.
  3. The spacecraft shall reach its stellar destination within a century of its launch, and ideally much sooner.
  4. The spacecraft design shall allow missions to a variety of target stars.
  5. The spacecraft propulsion shall be mainly fusion based.
  6. The spacecraft shall decelerate for increased encounter time at the destination.


This is what the team is now basing their work on and some of the higher level decisions that have already been made include the following (along the lines of MoSCoW format; Must, Should, Could, Would):


  • The spacecraft shall be decelerated sufficiently to allow it to enter orbit around a star in the Alpha Centauri A-B system.
  • The spacecraft shall arrive at the destination system no later than 100 years after the craft is launched.
  • The spacecraft should be able to carry a payload of 150 tonnes, but shall be able to carry a payload of at least 100 tonnes and shall be decelerated with the main spacecraft. (The payload mass does not include structural elements of the craft.)
  • The mission shall have the capability to make scientific measurements of the interstellar medium during the cruise phase to Alpha Centauri.
  • The mission shall have the capability to make scientific observations of at least one star in the Alpha Centauri system from a distance of at least one AU.
  • The mission shall have the capability to place scientific payloads into low orbit of no more than 1,000 km periapsis about at least one planet in the system for the purpose of high-resolution remote-sensing observations of the atmosphere and surface.
  • The mission should have the capability to deploy sub-probes to make in situ investigations of the atmospheres and surfaces of at least four planets in the Alpha Centauri System, including the capability of making in situ measurements at multiple locations on the same planet.
  • The mission could have the capability to deploy sub-probes to make in situ investigations of the atmospheres and surfaces of planets orbiting different stellar components of the system


Each submitted concept design report is expected to cover a description of the mission architecture, including assembly, launch and mission profile. It will also include estimates for the vehicle performance, including any individual acceleration or deceleration stages. This includes delta velocities, exhaust velocities, mass ratios, and specific power. A table of system masses will be given. The vehicle propulsion, thermal, power systems, risk analysis, failure modes, fuel and acquisition method will be described. The teams will be required to give a justification for the key choices made and technological maturity, put in the context of the original Daedalus design and today’s current or near-term technology. Given time and in order to place some context on the problem the teams will attempt a preliminary estimate of costs and analysis of risks to those costs (relative costs if necessary).