Alpha Centauri Explorer

[vidar]

Just to have mentioned it. I do not believe Einstein before I see the effects.<br /><br />However, that is not relevant for ACE because it is now considered a light speed project.<br />

 

[vidar]

I might have been unclear.<br /><br />I think the Orion project could have succeeded in sending a ship in tremendous speed towards a star and maybe been halfway to a star by now. <br /><br />But the crew would be dead, the ship beaten bad and had no chance of returning home.<br /><br />The idea is to send some automated scouts, like ACE, ahead to clear out the worst dangers in the path and the place.<br />

 

[dragon04]

When you're travelling in interstellar space at relativistic speeds, there is no such thing as clearing dangers in the "path".<br /><br />Everything in space is moving at all times. And because everything is moving, the "path" is constantly changing.<br /><br />Avoiding asteroidal sized bodies at relativistic speeds is very unlikely due to the velocities involved versus detection of the body.<br /><br />Avoiding golf ball sized objects would be virtually impossible. Impact with an object the size of a grain of sand at relativistic speeds would likely be catastrophic to an unshielded ship.<br /><br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[vogon13]

Before I read the Dyson book on Project Orion, I thought it was totally nuts.<br /><br />It's not.<br /><br />Very much worth additional research. Potential of the concept is staggering. 25 million tons (50 billion pounds) launch mass of an interstellar vehicle.<br /><br />Many concerns I had about the technology (efficiency of the nukes, erosion of the pusher plate) have been addressed. <br /><br />Also, some of the 'rough edges' seem more tractable now.<br /><br />I may work up some ideas and start a (pro) Orion concepts thread here. Seems like turning SDC team loose on it would be rather fun. Don't worry, I don't plan on building any hardware.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[yevaud]

Hey, Tap_Sa: that was sooooo familiar. I'm going to assume you once read the book, "Tau Zero?" <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[john_316]

u wont need to build an orion....<br /><br />i still have several xjr-45 saucers for sale.....<br /><br />real cheap too...<br /><br />

 

[vidar]

You are right it is not about clearing the path. Finding the path is more what I was thinking of.<br /><br />For example, avoiding high risk areas like ‘asteroid belts’, ‘Kuiper belts’, planets etc should be avoided for the next vessels. Such should be mapped by the first one.<br /><br />This means that the safest path would not be straight through the planetary plane. Maybe that is not the shortest path for the star systems. Maybe the planetary planes are in a different angle than the straight line between the stars. <br /><br />I do not think the velocity determines how likely it is to hit objects.<br />

 

[tap_sa]

<font color="yellow">"I'm going to assume you once read the book, "Tau Zero?""</font><br /><br />You assumed right <img src="/images/icons/smile.gif" /> I read it maybe 20 or so years ago, nice piece of classic hard scifi. Another one that comes to mind from that time and genre is Dragon's Egg. Living slugs on a neutron star evolving at nuclear speed <img src="/images/icons/laugh.gif" />

 

[lunatio_gordin]

But then you have to deal with, are all stars oriented the same way? Surely not every ecliptic plane is parallel. what's to say that Alpha Centauri's not 90 degrees off from Sol? these sorts of things could be important too.

 

[vidar]

Curiosity killed the cat too.<br /><br />Yes, we are going there sometimes and yes it will be hazardous for the first ones.<br />That is a main reason that I suggest very small scouts in the first place.<br />We need a map.<br />

 

[vidar]

I saw the movie Deep Impact yesterday. <br />And I noticed that the ship they built to nuke the comet, is actually an Orion ship. <br />They do not say much about it, except that it was an old concept and then it takes of with a blast.<br /><br />That made the film even more interesting, seeing an Orion ship in action.<br />

 

[le3119]

Alpha Centauri lies in the Earth's southern sky, about 60 degrees south latitude, so that's about 60 degrees (give or take) off the plane of the ecliptic (the plane through which the planets generally travel). So we wouldn't have to worry about asteroids on our way out of the Sun system, but we don't know what Kuiper - Oort type debris would pose a hazard to us.

 

[vidar]

That is good, just go straight at it.<br /><br />Isn’t the Kuiper belt a belt, which means that it is like a ring in line with the planets?<br />This Oort cloud is about 50-100 AU (I think) and thereby not very dense. Then collision there is not likely there.<br /><br />At the Alpha Centauri side, we know nothing. This is the hazardous part I suppose. There is no reason to assume that there are no asteroids, comets, belts and rings in addition to the planets and moons. I suppose the ACE should slow down at a distance of 100 AU and start sending pictures.<br />Hopefully, and probably, it does not arrive not in the planets’ plane.<br />

 

[lunatio_gordin]

It would help if they didn't shut off Voyager and Pioneer, and we could actually see what's beyond the heliopause.

 

[le3119]

The Kuiper and Oort objects are not just in belts parallel with the plane of the ecliptic, especially the Oort cloud, it is literally a cloud surrounding the solar system, and may extend out to 1+ lightyears. We'd have to revolutionize space navigation.

 

[ehs40]

what keeps the oort cloud around if it is so far past the heliopause??

 

[dragon04]

"what keeps the oort cloud around if it is so far past the heliopause??"<br /><br />The Sun's gravity. Although a passing star or large body can perturb an Oort cloud comet and either send in in towards the solar system or off into interstellar space.<br /><br /><br />http://www.solarviews.com/eng/oort.htm<br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[vidar]

Assuming Alpha Centauri also has an Oort cloud, there is no ‘space’ between the stars at all. There are merely planet systems and clouds. I suppose one can view the Oort clod and Kuiper belt as the suns own ring system.<br /><br />However, browsing through some articles about the Oort cloud, I found that ‘the Oort Cloud is a hypothesized sphere of frozen objects thought to start at about 10,000 AU and extend to 100,000 AU, or 1.5 light-years from the sun.’ It is hypothesized, not proven to be a cloud rather than a ring. <br /><br />What is the reason for assuming that the Oort is a cloud that also appears between the sun and the star?<br />

 

[cyrostir]

another problem is getting the information back - would take reallllly long<br /><br />think of the information of voyager - coming at /> 5 kb per sec - and people think dialup is slow!!!<br /><br /> new information sending technologies will definately be required for this mission <br /><br /><br /><br />also<br />building this spacecraft in space would save launch costs - and fuel<br /><br />think if we started to build a base on the moon - a manufacturing plant possibly - (when we have the technology of course) - then we start a martian base - next an europian base - finally after many years of progress we have plants on a body for each major planet - including pluto - think of the benefits from launching from pluto or charon or even just our moon - no gravity so no massive fuel weightage....<br /><br />this is a little farfected, I understand - but bare with me- just thinking ahead

 

[thalion]

I don't think anyone else has brought up the issue of time. I fully support an interstellar probe (though my preferred target would be Sirius rather than Alpha Centauri--getting to study two stars very different from the Sun instead of two near Sun-clones), but we need to know that unless we're willing to go through the immense expense of adding more fuel or energy to slow the probe, we'll be looking at a close encounter mission that will probably generate its most useful results over a matter of hours, for all the decades spent getting there. A probe traveling at .05c would cross the length of our Solar System out to Pluto in less than 18 days, and halve that for .10c.

 

[vidar]

I am still trying to find a safe path.<br /><br />It seems to me that the comets are Oort objects that somehow have been knocked out of a circular orbit. If so, the Oort cloud can still be a ring in the planetary plane, with some rough object. Still the Oort can be a ring rather than a sphere, couldn’t it?<br /><br />Still there are dangers of collide with object in interstellar journeys. Particles however, I do not think is possible to avoid. But what density of particle can one expect to encounter? Is it like the density commercial jet planes in our atmosphere meet, is it like what supersonic planes higher up meet, or is it more like the density submarines meets in water?<br /><br />Assuming an ACE at c/10 meet density of molecules like jet planes in our atmosphere, could it be used for an advantage like jets use air or cars use turbo?<br />

 

[vidar]

Still 5Kb/s is also 18Mb/hour at 24h/7d. That can bring in a lot of good pictures during a day.<br /><br />But there is a relation of velocity and transmission, since the signals will be stretched out due to some luminous However, in place at Alpha Centaury, only the relative velocity between the stars will influence. <br />

 

[vidar]

There sure is need for a lot more effective propulsion than the ordinary chemical rocket jets. That would gain both interstellar and interstellar travelling. <br /><br />Pluto, and the other planets, is not in the direction of Alpha Centauri. I do not think an ACE should have such a double mission as both explore this system and the neighbour. Hopefully, it is possible to go straight at the star, without encountering any objects in the path.<br />

 

[vidar]

"Nanotubes" have 100 times the tensile strength of steel, but only 1/6 the weight.<br />http://science.nasa.gov/headlines/y2005/27jul_nanotech.htm<br /><br />This can be useful for protecting the hull.<br />

 

[kdavis007]

Sounds like a good idea.. However we need a ship that could take at least a month to get to Alpha Centauri...