Update:
Interstellar space travel may be a little while off yet.
See here.
Yesterday was an interesting day in scientific news. First I read that it is now possible to use the Sun’s energy to propel a craft through space. This is an interesting idea, and even more interesting are the details of the project. It is a privately funded project and the rocket taking this ’sailing ship’ to space is an ex-intercontinental (are you allowed to put two prefixes on a word?) missile launched from a submarine.
A solar sail is pushed directly by photons, light particles from the Sun, reflecting off sets of large mirror-like sails. Because a solar sail carries no fuel and keeps accelerating over almost unlimited distances, it is a technology often pointed to that can propel interstellar travel into reality.
Reflected light pressure will push against Cosmos 1’s eight reflective blades, designed to adjust to the continuously changing orbital energy and spacecraft velocity. Cosmos 1 will be the first attempt to sail under sunlight pressure.
I have read a fair number of news articles on this (but not delved much further into the detail) and I see a problem with stopping this thing. Once it gets going there is no friction to slow it down so you’ll need a force in the other direction. I guess they aren’t looking to stop it at this stage, but these guys think it’s possible, not only to stop, but to turn around and come back!
After the crew explores the system for a few years (using their lightsail as a solar sail), it will be time to bring them back. To do this, a 100-kilometer-diameter (62-mile-diameter) return sail is separated from the center of the 320-kilometer rendezvous sail. The laser light from our solar system hits the ring-shaped remainder of the rendezvous sail and is reflected back on the return sail, sending it on its way back to the solar system. As the return sail approaches the solar system 20 Earth-years later, it is brought to a halt by a final burst of laser power. The members of the crew have been away 51 years (including 5 years of exploring), have aged 46 years, and are ready to retire and write their memoirs.
And why wouldn’t I believe them?
The second big thing, as the title suggests, is that it may soon be possible to reproduce without sex or birth. Exactly why you would want to forgo the first, I’m not sure.
Scientists have raised the possibility that fertilised human embryos might be created in a laboratory dish from artificial sperm and eggs before being implanted in the womb.
But as this article states, there is a fairly good reason for the idea (of course there might be a reason why people are unable to reproduce naturally, but I’ll leave that up to you to decide).
Monash researchers have developed a process that causes embryonic stem cells to develop into ovarian structures containing eggs.
Monash researcher Orly Lacham-Kaplan said the process could eventually be used to develop eggs for sterile women that contain the women’s own genetic material.
But, what about the birth thing you might ask? Well if you combine that technology with this one (which some are suggesting is the go)….
…science is closing in on an artificial womb that may make gestation possible outside a woman’s body.
The world could be an interesting place in 50 or 100 years, even more so than now! I hope I’m around to see it.
It occurs to me that, since the thrust is provided by photons reflecting off the sail, and since every photon hitting the return sail will have already hit the remains of the other sail, the two thrusts should cancel out. I’m sure they’ve thought it out, but, from what they said there, I really can’t see how the return sail idea is going to work.
greymullet
22 Jun 05 at 9:51 pm