anti-sunward

adverb

an·​ti-sun·​ward ¦an-tī-¦sən-wərd 

¦an-tē-

variants or antisunward

astronomy

: away from the sun : in the direction of the anthelion

The most prominent optical feature of C/LINEAR was the tail of dust extending antisunward of the predicted position of the nucleus, which is also nearly due east.

—H. A. Weaver et al., Science, 18 May 2001

anti-sunward adjective

or antisunward

These forces accelerate the ions rapidly in the anti-sunward direction, producing the narrow tails often seen in comets.

—Daniel Boice et al., Encyclopedia of the Solar System, 1999

Word History

Etymology

antisun + -ward entry 2

First Known Use

1974, in the meaning defined above

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