How long would a trip to mars take?

[ew1962]

I was just wondering how long a trip to mars would take?

 

[MeteorWayne]

Generally, using current technology (current rockets) it takes 6-8 months.<br />That assumes the launch takes place at the best time, when Earth and Mars are closest, every 2 years or so. <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[heyscottie]

A round trip will take somewhere around 2.5 years: 6-8 months travel there, about a year on the surface waiting for the next favorable planetary alignment, (and hopefully doing lots of science), and 6-8 months travel back.<br />

 

[ew1962]

Thanks everyone for the reply! Is there a space ship designed yet that could take people to mars or has one been designed?

 

[star_sirius]

Thanks heaps, there're awesome videos in that link: <img src="/images/icons/cool.gif" /><br /><br />http://video.google.com/videosearch?q=VASIMR <div class="Discussion_UserSignature"> <font size="0" color="#10bdee"><strong>A dazzling bluish luminosity from A distant south pacific.</strong></font><p><br /><img id="cb51e87e-8221-424c-8ff2-78c95122196c" src="http://sitelife.livescience.com/ver1.0/Content/images/store/11/15/cb51e87e-8221-424c-8ff2-78c95122196c.Large.jpg" alt="blog post photo" /></p> </div>

 

[ew1962]

Thanks! First time I have seen this. It is a great site.

 

[willpittenger]

However, a manned mission would probably take longer due to the vehicle being more massive. The return trip will be more so. That could take as much as 3 years. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[willpittenger]

<blockquote><font class="small">In reply to:</font><hr /><p>It's possible to get there faster, of course, but to do so requires that you sacrifice payload capacity.<p><hr /></p></p></blockquote><br />Or use some monster engines. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[qso1]

Shuttle_guy mentioned 39 days for VASIMR type propulsion. I've seen three months for VASIMR type propulsion but either way, its a heck of a lot faster than nuclear thermal which would get you to mars in the 6-8 month timeframe mentioned here.<br /><br />If they can actually get down to 39 days, mars will be much easier to deal with as a manned mission program. <div class="Discussion_UserSignature"> <p><strong>My borrowed quote for the time being:</strong></p><p><em>There are three kinds of people in life. Those who make it happen, those who watch it happen...and those who do not know what happened.</em></p> </div>

 

[docm]

I guess the trick is getting a reactor small & light enough it won't be a mass issue and powerful enough to drive the VASIMR(s) while not needing radiators the size of Rhode Island. The Brayton cycle would work for power generation (gas driven turbines) and pebble bed reactors are easy to fuel, gas cooled, simple & safe though they're weak on power density. <div class="Discussion_UserSignature"> </div>

 

[nyrath]

<blockquote><font class="small">In reply to:</font><hr /><p>However, a manned mission would probably take longer due to the vehicle being more massive.<p><hr /></p></p></blockquote><br />That turns out not to be the case. <img src="/images/icons/wink.gif" /><br />A Hohmann trajectory to Mars takes 8.6 months, regardless of how massive the vehicle is.<br /><br />If the vehicle is too massive for its engines to give it enough delta V to enter the Hohmann trajectory, it does <b>not</b> take longer to get there. Instead it cannot make the journey at all.<br /><br />http://www.projectrho.com/rocket/rocket3b.html

 

[willpittenger]

How far is VASIMR from being usable on a manned mission? That would have to include practical shielding for any required reactor. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[docm]

VASIMR is supposed to fly an LEO test mission by 2010 using a solar array. <br /><br />It recently ran for 4 straight hours and more tests, presumably longer, are due. They envision using it for boosting satellites to higher orbits first then space station reboosting. <br /><br />Wouldn't it be a hoot if they used it in a Bigelow propulsion bus? <img src="/images/icons/wink.gif" /><br /><br />Shielding for space reactors has already been looked at and largely solved. Contrary to what many believe it can be done with a relatively lightweight composite of high density polyethylene and/or various layered materials. <br /><br />Examples; lithium6 hydride-tungsten, boron10 carbide-tungsten and lithium6 hydride-beryllium. These shield both neutrons and gamma. <br /><br />The polyethylene and hydrides are high enough in hydrogen to act like water blankets if thick enough. <br /><br />Berylliums strong point is that it's a neutron reflector. Boron10 and Lithium6 absorb thermal neutrons as well as the spallation neutrons produced by protons hitting the polyethylene shielding. Carbon (in the carbide) is a neutron moderator. <br /><br />Tungsten is just plain DENSE and better than lead in high energy applications. In powdered form it can also be added to the polyethylene shields. <br /><br />These don't take levels down to zero, that would take meters of lead, but combined with other methods (put the reactor at one end of a longish ship & the hab at the other like Discovery) it's enough. <div class="Discussion_UserSignature"> </div>