Paper: Easily Retrievable Asteroids Discovered
Easily Retrievable Objects among the NEO Population, arXiv.org
“Asteroids and comets are of strategic importance for science in an effort to understand the formation, evolution and composition of the Solar System. Near-Earth Objects (NEOs) are of particular interest because of their accessibility from Earth, but also because of their speculated wealth of material resources.
The exploitation of these resources has long been discussed as a means to lower the cost of future space endeavours. In this paper, we consider the currently known NEO population and define a family of so-called Easily Retrievable Objects (EROs), objects that can be transported from accessible heliocentric orbits into the Earth’s neighbourhood at affordable costs.
… Despite the highly incomplete census of very small asteroids, the ERO catalogue can already be populated with 12 different objects retrievable with less than 500 m/s of {\Delta}v. Moreover, the approach proposed represents a robust search and ranking methodology for future retrieval candidates that can be automatically applied to the growing survey of NEOs.”
It’s worth noting that even though the link is to the paper on arXiv, it has been submitted for peer review as well:
http://link.springer.com/ar…
pre-print submission to places like arXiv are becoming more and more common in the math and physics research communities.
And what exactly is the value of doing this? As opposed to
establishing a permanent presence on the moon?
—John
It all depends on what “this” is. The only purpose for the current asteroid retrieval and rendezvous mission seems, IMHO, is to give something for SLS to do (test its lackluster BEO abilities) until a Mars mission becomes feasible. I personally think that the asteroid mission would be wonderful if it focused on pushing forward resource extraction/utilization technologies for asteroids vice the vague “science mission” that is planned. Also, why can we not have both a moon base operation and NEO operations? Outside of limited funding there should be no reason they are mutually exclusive. Actually a NEO operation at one of the moon lagrange points could very well be beneficial to a (surface) moon base.
Baby steps?
Some unexamined assumptions:
– Visiting the Moon is important and contributes toward colonization of space
– Visiting Mars is important and contributes toward colonization of space
– Visiting an asteroid as an SLS mission isn’t a first step toward asteroid mining and ISRU
“Establishing a permanent presence in space” is a different goal than “establishing a permanent presence on the Moon”.
For the long term, the first goal is more important, and an automatic unexamined assumption that the second is important actually gets in the way of the first, whose importance is well-established and easy to prove.
We could establish a permanent, self-sufficient, Earth-gravity, radiation-shielded presence in space without ever going back to the Moon or Mars, and it may be much easier to do so.
I think there’s a slight error in the article. Asteroids and their like may have been discussed as a means of lowering cost to low earth orbit but that’s just wrong. The fact that current methods mean using one-off launch vehicles means you can’t influence cost very much.
Presumably the authors are referring to spreading the fixed costs of the launch companies across a number of launches however that’s really just wishful thinking. It didn’t work with the EELV program and you need to really get the launch rate up to get any meaningful reduction. Again, reducing the manufacturing and launch costs would help but none of the current crop are working on this. They’re interested in shareholder return, not cost reduction.
SpaceX is the only launch company seriously working on reusable launch vehicles and cost reduction overall. One reason why they have a launch manifest of something like 50 launches with more than 50% being strictly commercial. It’s also public knowledge that the existing players (ESA, ULA, China) can’t compete with their pricing.
They also aren’t driven purely by ROI. They’re stated long-term goal is to facilitate the human race into a multi-planet species.
That said, they do need to start flyiing those missions demonstrating the ability to launch consistently and successfully as well as maintain their pricing.
Discussed by whom? Asteroid-derived fuel is suggested as a way to reduce costs for trans-orbit flight, never for Earth launch to LEO.
(The article talks of the cost of reaching different asteroid targets from Earth, it doesn’t refer to asteroid refuelling or any similar advanced concept.)