What ever happened to some of the older Martian orbiters?

[willpittenger]

This question concerns Mariner 9, the Viking orbiters, and any Soviet orbiters. Would those orbiters have crashed by now? Or could we expect to encounter them when we arrive at Mars? To some extent, we would have to deal with orbital debris. That might not seem to be a problem with the low number of objects compared to what we face here. However, at least we can track objects in LEO.<br /><br />How do you track an object orbiting Mars? Also, now that MGS appears to have died, what will happen to its orbit? I figure that if it were functioning, its thrusters would have maintianed that orbit for some time. But now... <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>

 

[brellis]

These spacecraft are built to last, that's for sure -- they pinged Pioneer 6 on its 35th Anniversary, and got a response just as they expected! <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[JonClarke]

Mars does not have mascons like the Moon, so orbits are more stable. But there is atmosphere drag, so eventually the satllites will enter the atmosphere. I have no idea generally what the predicted life of historical orbiters is. However, Carl Sagan once wrote that Mariner 9 would last for about 50 years before entering the Martian atmosphere. That means it and Mars 2 and 3 should last until 2021.<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[rybanis]

Thats amazing!<br /><br />I'm kinda curious as to how the Viking orbiters are doing (as it has been mentioned already). Would there be a place to look? <div class="Discussion_UserSignature"> </div>

 

[MeteorWayne]

From NASA/Missions/Past Missions/Viking 1<br /><br />"On 7 August 1980 Viking 1 Orbiter was running low on attitude control gas and its orbit was raised from 357 x 33943 km to 320 x 56000 km to prevent impact with Mars and possible contamination until the year 2019."<br /><br />Viking 2 "It was placed in a 302 x 33176 km orbit and turned off on 25 July 1978 after returning almost 16,000 images in 706 orbits around Mars. "<br /><br /> Viking Page <br /> <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>