Project Lyra is a feasibility study of a mission to

interstellar object An interstellar object is an astronomical object in interstellar space that is not gravitationally bound to a star. Applicable objects include asteroids, comets, and rogue planets, but not a star or stellar remnant. This term can also be appli ...

s such as

ʻOumuamua Oumuamua is the first confirmed interstellar object detected passing through the Solar System. Naming of comets#Current system, Formally designated 1I/2017 U1, it was discovered by Robert Weryk using the Pan-STARRS telescope at Haleakalā O ...

and

2I/Borisov 2I/Borisov, originally designated C/2019 Q4 (Borisov), is the first observed rogue comet and the second observed interstellar interloper after ʻOumuamua. It was discovered by the Crimean Amateur astronomy, amateur astronomer and telescope make ...

, initiated on 30 October 2017 by the

Initiative for Interstellar Studies The Initiative for Interstellar Studies (i4is) is a UK-registered not-for-profit company, whose objectives are education and research into the challenges of Interstellar Travel. It pioneered small-scale laser sail interstellar probes (Project Dra ...

(i4is). In January 2022, researchers proposed that a spacecraft launched from Earth could catch up to 'Oumuamua in 26 years for further close-up studies.

Overview

Options suggested by i4is initially (which have now been superseded) for sending a spacecraft to ʻOumuamua within a time-frame of 5 to 10 years were based on a launch in 2021, and required travelling first to Jupiter to conduct a flyby, followed by a close solar flyby at 3 to 10 solar radii, in order to take advantage of the

Oberth effect In astronautics, a powered flyby, or Oberth maneuver, is a maneuver in which a spacecraft falls into a gravitational well and then uses its engines to further accelerate as it is falling, thereby achieving additional speed. The resulting maneuve ...

. Subsequent research revealed further launch possibilities, notably in 2030 or 2033, using the same scenario (except the 2030 launch has an additional Vinfinity Leveraging Maneuver), but with a total flight duration of 22 years. Thus, there are still future opportunities for a mission to 'Oumuamua. Furthermore alternative trajectory options were also explored by i4is, all of which utilized the much less technically challenging Jupiter Oberth rather than the previously assumed Solar Oberth. Launch years for these range between 2026 and 2033, depending on the chosen combination of gravity assists leading up to the Jupiter encounter. Alternatively i4is proposed more advanced options such as a

solar sail Solar sails (also known as lightsails, light sails, and photon sails) are a method of spacecraft propulsion using radiation pressure exerted by sunlight on large surfaces. A number of spaceflight missions to test solar propulsion and navigati ...

, laser sail, or

nuclear propulsion Nuclear propulsion includes a wide variety of propulsion methods that use some form of nuclear reaction as their primary power source. Many aircraft carriers and submarines currently use uranium fueled nuclear reactors that can provide propulsio ...

Solar Oberth

ʻOumuamua was at first thought to be traveling too fast for any existing spacecraft to reach. The

(i4is) launched Project Lyra to assess the feasibility of a mission to ʻOumuamua. Several options for sending a spacecraft to ʻOumuamua within a time-frame of 5 to 25 years were suggested. The challenge highlighted by i4is is to get to the asteroid in a reasonable amount of time (and so at a reasonable distance from Earth), and yet be able to gain useful scientific information. To do this, decelerating the spacecraft at ʻOumuamua would be "highly desirable, due to the minimal science return from a hyper-velocity encounter". If the investigative craft goes too fast, it would not be able to get into orbit or land on the asteroid, and would fly past it. The authors conclude that, although challenging, an encounter mission would be feasible using near-term technology. Seligman and Laughlin adopt a complementary approach to the Lyra study, but also conclude that such missions, though challenging to mount, are both feasible and scientifically attractive. One option suggested by i4is is using first a Jupiter flyby, followed by a close solar flyby at , in order to take advantage of the

. Subsequent proposals have relaxed the distance to up to . Initial research conducted by i4is indicated that a spacecraft with a mass of tens of kilograms, using a heat shield like that in the

Parker Solar Probe The Parker Solar Probe (PSP; previously Solar Probe, Solar Probe Plus or Solar Probe+) is a NASA space probe launched in 2018 to make observations of the Stellar corona, Sun's outer corona. It used repeated Gravity assist, gravity assists from ...

, atop a

Falcon Heavy Falcon Heavy is a super heavy-lift launch vehicle with partial reusability that can carry cargo into Earth orbit and beyond. It is designed, manufactured and launched by American aerospace company SpaceX. The rocket consists of a center core ...

-class launcher, with a trajectory including a powered Jupiter flyby and a Solar Oberth maneuver, was capable of reaching ʻOumuamua, had it been launched in 2021. However, subsequent investigations revealed further opportunities for missions to 'Oumuamua will be possible, using a Solar Oberth at , the soonest being in 2030/2033 – the choice of year depending on whether the trajectory exploits a 3 year leveraging maneuver or not. These involve flight durations in excess of 20 years which, although admittedly protracted, should be placed in the context of the

Voyager probes The Voyager program is an American scientific program that employs two interstellar probes, ''Voyager 1'' and ''Voyager 2''. They were launched in 1977 to take advantage of a favorable planetary alignment to explore the two gas giants Jupiter ...

, which launched over 45 years ago and are still to some extent operational today.

Jupiter Oberth

Further investigations conducted by the i4is Project Lyra team revealed that viable missions to 'Oumuamua exist in the future, with launch for example in 2028, and do not necessarily require a Solar Oberth, exploiting instead a powered flyby of Jupiter, alternatively known as a Jupiter Oberth.

Other options

More advanced options such as solar,

laser electric propulsion Laser propulsion is a form of beam-powered propulsion where the energy source is a remote (usually ground-based) laser system and separate from the reaction mass. This form of propulsion differs from a conventional chemical rocket where both energy ...

, laser sail propulsion based on

Breakthrough Starshot Breakthrough Starshot is a research and engineering project by the Breakthrough Initiatives to develop a proof-of-concept fleet of light sail interstellar probes named ''Starchip'', to be capable of making the journey to the Alpha Centauri st ...

technology, and nuclear propulsion have also been considered.

References

{{Reflist Spaceflight concepts Proposed space probes Hyperbolic asteroids Interstellar travel

External links

Initiative for Interstellar Studies

2D Animation of Project Lyra with Solar Oberth Manoeuvre

Institute for Interstellar Studies (US)

Principium – Quarterly Publication of i4is

Oumuamua: A Second Chance? A Personal Memoir