
1) Cool, very red celestial body 2) Sky spectral type 3) Spectral type 4) Very red heavenly body
Found on
https://www.crosswordclues.com/clue/nstar

NSTAR is a utility company that provides retail electricity and natural gas to 1.4 million customers in eastern and central Massachusetts, including the Boston urban area. NSTAR was formed in 1999 by the merger of BEC Energy and Commonwealth Energy System and currently has the following operating units: Boston Edison Company, Cambridge Electric Li...
Found on
http://en.wikipedia.org/wiki/NSTAR

DS1 firing its NSTAR ion propulsion system in a vacuum chamber at the Jet Propulsion Laboratory prior to launch An electron bombardment thruster – a type of ion propulsion system – developed by NASA and Hughes Research Laboratories (now part of Boeing). It was used to propel the Dee...
Found on
http://www.daviddarling.info/encyclopedia/N/NSTAR.html
No exact match found.