A number of years back, while on Linux Mint 11, in the Software Store(not the actual name but you get the idea) I happened across Celestia, a fun little Astronomy program.  It seems as though it has been wiped out since then.  Is there somewhere I can get this program for installation in Ubuntu 18.04?  I really enjoyed this program, and would like to have it again.
Like the title said, I want to install Celestia. I already downloaded the packages  and then, I tried all the things that I found on some posts (also, they're outdated, cause the last one is for Ubuntu 16.04) but nothing works.  How can I install it on Ubuntu 18.04.1?
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Book about almost extinct warrior race with three castes: sen, kaa, ker The aliens in this book are an humanoid alien mercenary race, fighting for some other aliens, against humans?.   The Ker are the fighters, the sen are the wise ones, and the kaa the family/non-fighters.  Their clan gets almost wiped out because both their employers and humanity fear them, and the last survivors head towards their race' home planet, together with a human captive, who learns about their ways.  The other aliens are some blob-like aliens with little genetic variety.  Ring any bells? Changing geometry types from kml points Z to just points in QGIS How do I change geometry types from pointZ to point in QGIS from a kmz file? I want to make a generic class that accepts only serializable classes, can it be done with the where constraint?  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