Astra comes from the Greek astron, meaning "star" — the same root that gives "astronomy," "astrology," "astronaut," and "asterisk." The Latin phrase ad astra ("to the stars") gives Astra particular literary weight.
Astra is rising as part of the broader return of celestial names. Today it remains rare but distinctive.
Astra does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
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In Pythagorean numerology the letters of Astra reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.