Modx evolution 1.02 error

I am getting the following error any ideas as to why?

« MODx Parse Error »

MODx encountered the following error while attempting to parse the requested resource:
« Execution of a query to the database failed - Table ’./stargate_kmagmodx/kmag_site_content’ is marked as crashed and should be repaired »
SQL: SELECT DISTINCT sc.id, sc.menutitle, sc.pagetitle, sc.introtext, sc.menuindex, sc.published, sc.hidemenu, sc.parent, sc.isfolder, sc.description, sc.alias, sc.longtitle, sc.type,if(sc.type=’reference’,sc.content,’’) as content, sc.template, sc.link_attributes FROM `stargate_kmagmodx`.`kmag_site_content` sc LEFT JOIN `stargate_kmagmodx`.`kmag_document_groups` dg ON dg.document = sc.id WHERE sc.published=1 AND sc.deleted=0 AND (sc.privateweb=0) AND sc.hidemenu=0 AND sc.id IN (1,270,427,2,3,4,26,6,7,546,1309,1858,15,16,46,111,1288,86) GROUP BY sc.id ORDER BY sc.menuindex ASC ;
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Parser timing
MySQL: 0.0036 s (0 Requests)
PHP: 0.1639 s
Total: 0.1675 s

Table ’./stargate_kmagmodx/kmag_site_content’ is marked as crashed and should be repaired

this tells you why. You need to repair the table. If your hosting control panel provides phpMyAdmin, you can do it from the Operations tab, near the bottom it’s in the Table Maintenance block.