<story><title>House tells NASA to start planning two Europa missions</title><url>http://arstechnica.com/science/2016/05/house-budget-provides-260-million-for-two-life-tracking-europa-missions/</url></story><parent_chain></parent_chain><comment><author>Ankaios</author><text>Note that the text that came out of the subcommittee (&lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;appropriations.house.gov&amp;#x2F;uploadedfiles&amp;#x2F;bills-114hr-sc-ap-fy2017-cjs-subcommitteedraft.pdf&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;appropriations.house.gov&amp;#x2F;uploadedfiles&amp;#x2F;bills-114hr-sc...&lt;/a&gt;) mandates that NASA use the Space Launch System (SLS) to launch the missions.&lt;p&gt;SLS is a stunningly overpriced rocket that Congress is forcing NASA to build to keep former shuttle contractors and NASA centers employed. Congress is sending ~ $1.8 billion every year to states including Alabama, Florida, Utah, and Louisiana to develop it. There are very few payloads manifested for it. Launching the Europa missions on it would be a tremendous waste of money—the benefits would not warrant the cost.&lt;p&gt;It would be worth exploring the lobbying performed by SLS contractors including Boeing and Orbital ATK, as well as that of people close to the main NASA centers involved with SLS, the Marshall Space Flight Center in Alabama and the Kennedy Space Center in Florida.</text></comment>
<story><title>House tells NASA to start planning two Europa missions</title><url>http://arstechnica.com/science/2016/05/house-budget-provides-260-million-for-two-life-tracking-europa-missions/</url></story><parent_chain></parent_chain><comment><author>avz</author><text>While water is not uncommon in space, liquid water is a very rare. This is due to the fact that liquids in general can only exist in a relatively narrow range of temperatures and pressures (see phase diagram [1]).&lt;p&gt;Europa is one of the few places in the Solar system where we expect to find liquid water. One of the others is Mars, but most water there is solid - only small amounts of it occur in liquid form and only briefly. By contrast, Europa has a freaking underground ocean! Moreover, by some estimates it is larger in volume than all oceans on Earth combined [2].&lt;p&gt;Should we go check it out? Hell yeah!&lt;p&gt;[1] &lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Phase_diagram&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;en.wikipedia.org&amp;#x2F;wiki&amp;#x2F;Phase_diagram&lt;/a&gt;
[2] &lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;apod.nasa.gov&amp;#x2F;apod&amp;#x2F;ap120524.html&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;apod.nasa.gov&amp;#x2F;apod&amp;#x2F;ap120524.html&lt;/a&gt;</text></comment>