nova
    n 1: a star that ejects some of its material in the form of a
         cloud and become more luminous in the process

Nova \No"va\ (n[=o]"v[.a]), n.; pl. L. Novae (n[=o]"v[=e]), E.
   Novas (n[=o]"v[.a]z). [L., fem. sing. of novus new.]
   (Astron.)
   A star which suddenly increases in brightness thousands of
   times, then fades back to near its original intensity. It may
   appear as a "new" star if its original brightness was too low
   for routine observation. A star which suddenly increases in
   brightness to many millions of times its original intensity
   is a supernova, and the postulated mechanisms for the
   increases of brightness of novae and supernovae are
   different.

   Note: The most important modern novae are:

   No"va Co*ro"nae Bo`re*a"lis[1866];

   No"va Cyg"ni[1876];

   No"va An*dro"me*dae[1885];

   No"va Au*ri"gae[1891-92];

   No"va Per"se*i[1901]. There are two novae called Nova
      Persei. They are:
   (a) A small nova which appeared in 1881.
   (b) An extraordinary nova which appeared in Perseus in 1901.
       It was first sighted on February 22, and for one night
       (February 23) was the brightest star in the sky. By July
       it had almost disappeared, after which faint surrounding
       nebulous masses were discovered, apparently moving
       radially outward from the star at incredible velocity.
       [Webster 1913 Suppl. +PJC]

Nova

    A minicomputer(?) introduced by Data General
   in 1969, with four 16-bit accumulators, AC0 to AC3, and a
   15-bit program counter.  A later model also had a 15-bit
   stack pointer and frame pointer.  AC2 and AC3 could be
   used for indexed addressing and AC3 was used to store the
   return address on a subroutine call.  Apart from the small
   register set, the NOVA was an ordinary CPU design.

   Memory could be accessed indirectly through addresses stored
   in other memory locations.  If locations 0 to 3 were used for
   this purpose, they were auto-incremented after being used.  If
   locations 4 to 7 were used, they were auto-decremented.
   Memory could be addressed in 16-bit words up to a maximum of
   32K words (64K bytes).  The instruction cycle time was 500
   nanoseconds(?).  The Nova originally used core memory,
   then later dynamic RAM.

   Like the PDP-8, the Data General Nova was also copied, not
   just in one, but two implementations - the Data General
   MN601 and Fairchild 9440.  Luckily, the NOVA was a more
   mature design than the PDP-8.

   Another CPU, the PACE, was based on the NOVA design, but
   featured 16-bit addresses (instead of the Nova's 15), more
   addressing modes, and a 10-level stack (like the Intel
   8008).

   [Speed, mini?]

   (2003-10-23)