<story><title>China lands Chang&apos;e-4 on far side of Moon</title><url>http://www.planetary.org/blogs/jason-davis/change4-success.html</url></story><parent_chain><item><author>A2017U1</author><text>Copying earlier comment:&lt;p&gt;Wikipedia seems to say the rover mission duration is 3 months, yet the previous rover traveled for a year and transmitted a bit longer. The Chinese seemed quite coy about it failing last time (as with many things) so perhaps underpromising in this case?&lt;p&gt;This all preparation for China&amp;#x27;s planned permanent radio telescope on the far side which would be a huge boon for astronomers by escaping Earth&amp;#x27;s EM interference.&lt;p&gt;Also out left field is the 3kg &amp;quot;self sustaining&amp;quot; biosphere of silkworms and plants with a camera inside. Interested to see how long it survives.</text></item></parent_chain><comment><author>brainwipe</author><text>Regarding underpromising - there might be a little management of expectations but to paraphrase a friend in &amp;quot;the biz&amp;quot;: facing away from the Earth means that the stuff you need to be reliable jumps up in complexity and with that complexity comes a foreshortening of life. She then babbled incoherently in a way I enjoyed but didn&amp;#x27;t understand.&lt;p&gt;Love the idea of a dark side telescope!</text></comment>
<story><title>China lands Chang&apos;e-4 on far side of Moon</title><url>http://www.planetary.org/blogs/jason-davis/change4-success.html</url></story><parent_chain><item><author>A2017U1</author><text>Copying earlier comment:&lt;p&gt;Wikipedia seems to say the rover mission duration is 3 months, yet the previous rover traveled for a year and transmitted a bit longer. The Chinese seemed quite coy about it failing last time (as with many things) so perhaps underpromising in this case?&lt;p&gt;This all preparation for China&amp;#x27;s planned permanent radio telescope on the far side which would be a huge boon for astronomers by escaping Earth&amp;#x27;s EM interference.&lt;p&gt;Also out left field is the 3kg &amp;quot;self sustaining&amp;quot; biosphere of silkworms and plants with a camera inside. Interested to see how long it survives.</text></item></parent_chain><comment><author>sowbug</author><text>I&amp;#x27;d interpret the stated duration as a criterion for whatever budget they came up with. Building something that&amp;#x27;ll last 90 days in a harsh environment is a lot less expensive than one that needs to last at least a year. And assuming the folks monitoring the rover aren&amp;#x27;t working for free, the budget needs to include their cost of employment for a fixed amount of time.</text></comment>