Names to add to your shortlist
Altair
Altair had just 16 published U.S. births in 2025 at #5,618, putting this exact spelling deep into rare-name territory.
2025 U.S.: 16 births · #5,618Peak: 2024 · 26 births
Apollo
Apollo recorded 708 U.S. births in 2025 at #445; it is distinctive, although not among the statistically rarest choices on the site.
2025 U.S.: 708 births · #445Peak: 2022 · 820 births
Castor
Bold enough for a celestial shortlist, it gives the shortlist a different sound from today’s most common choices.
2025 U.S.: 21 births · #4,734Peak: 2016 · 29 births
Cosmo
Space-inspired without blending into the usual list, it stands apart without asking for a creative spelling.
2025 U.S.: 80 births · #1,934Peak: 2022 · 99 births
Elio
Elio reached its highest published U.S. count in 2025 with 818 births, so this uncommon spelling is currently at a historical high.
2025 U.S.: 818 births · #388Peak: 2025 · 818 births
Galileo
Galileo recorded 25 U.S. births in 2025 at #4,172, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 25 births · #4,172Peak: 2022 · 44 births
Helios
Helios reached its highest published U.S. count in 2025 with 58 births, so this uncommon spelling is currently at a historical high.
2025 U.S.: 58 births · #2,367Peak: 2025 · 58 births
Kepler
Space-inspired without blending into the usual list, it feels intentional rather than unusual for the sake of being unusual.
2025 U.S.: 25 births · #4,195Peak: 2016 · 42 births
Mars
Mars recorded 105 U.S. births in 2025 at #1,615, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 105 births · #1,615Peak: 2023 · 154 births
Oberon
Oberon had just 17 published U.S. births in 2025 at #5,544, putting this exact spelling deep into rare-name territory.
2025 U.S.: 17 births · #5,544Peak: 2021 · 37 births
Orion
Bold enough for a celestial shortlist, it is a strong candidate to test beside your surname.
2025 U.S.: 1,012 births · #334Peak: 2018 · 1,152 births
Phoenix
Phoenix recorded 1,027 U.S. births in 2025 at #329; it is distinctive, although not among the statistically rarest choices on the site.
2025 U.S.: 1,027 births · #329Peak: 2020 · 1,534 births
Rigel
Rigel had just 19 published U.S. births in 2025 at #5,158, putting this exact spelling deep into rare-name territory.
2025 U.S.: 19 births · #5,158Peak: 2016 · 34 births
Sagan
Sagan had just 17 published U.S. births in 2025 at #5,572, putting this exact spelling deep into rare-name territory.
2025 U.S.: 17 births · #5,572Peak: 2018 · 63 births
Sirius
Sirius recorded 33 U.S. births in 2025 at #3,500, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 33 births · #3,500Peak: 2022 · 61 births
Sol
Sol recorded 184 U.S. births in 2025 at #1,151, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 184 births · #1,151Peak: 1918 · 321 births
Solstice
Skyward and distinctive, it is a strong candidate to test beside your surname.
2025 U.S.: 8 births · #9,589Peak: 2022 · 10 births
Starling
Starling has a much stronger historical footprint than its current use: 26 births at its 1920 peak versus 13 in 2025.
2025 U.S.: 13 births · #6,753Peak: 1920 · 26 births
Titan
Titan recorded 151 U.S. births in 2025 at #1,295, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 151 births · #1,295Peak: 2017 · 421 births
Zenith
Zenith recorded 40 U.S. births in 2025 at #3,087, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 40 births · #3,087Peak: 2022 · 59 births
Zephyr
Zephyr recorded 169 U.S. births in 2025 at #1,203, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 169 births · #1,203Peak: 2022 · 195 births
Caelum
A cosmic choice with a clear sound, it has a clear rhythm that is easy to remember.
2025 U.S.: 97 births · #1,690Peak: 2025 · 97 births
Cyrus
Bold enough for a celestial shortlist, it stands apart without asking for a creative spelling.
2025 U.S.: 1,284 births · #268Peak: 2024 · 1,389 births
Aster
Space-inspired without blending into the usual list, it is a strong candidate to test beside your surname.
2025 U.S.: 43 births · #2,888Peak: 2024 · 46 births
Astro
Astro recorded 55 U.S. births in 2025 at #2,453, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 55 births · #2,453Peak: 2023 · 73 births
Sky
Sky recorded 101 U.S. births in 2025 at #1,661, keeping this exact spelling well beyond the most-used 1,000 boy names.
2025 U.S.: 101 births · #1,661Peak: 2014 · 124 births
Vesper
Vesper had just 8 published U.S. births in 2025 at #9,644, putting this exact spelling deep into rare-name territory.
2025 U.S.: 8 births · #9,644Peak: 2024 · 12 births
Lucero
Lucero had just 6 published U.S. births in 2025 at #11,475, putting this exact spelling deep into rare-name territory.
2025 U.S.: 6 births · #11,475Peak: 1991 · 21 births
Aquila
Skyward and distinctive, it feels intentional rather than unusual for the sake of being unusual.
2025 U.S.: 10 births · #7,713Peak: 2021 · 17 births
Janus
SSA published no 2025 count for Janus; this exact spelling had either zero to four U.S. male births nationally.
2025 U.S.: no published countPeak: 1997 · 6 births
The data line uses the exact spelling shown. “No published 2025 count” can mean the spelling had zero births or fewer than five, because SSA does not publish counts below five.
Celestial names range from subtle to bold
Elio and Cyrus can hint at a bright, skyward style without sounding like astronomy terms. Rigel, Kepler and Sirius make the connection much more direct.
Check the story behind the object
Astronomical names often come with mythology, science or historical associations. If one makes your shortlist, learn the specific reference so you know the story you are choosing.
Space-inspired does not always mean rare
Some celestial names have moved quickly into the mainstream. Current counts help you separate a cosmic style from actual rarity.
Roscoe's pick
Cosmo
Cosmo makes the space connection obvious, but its long history as a given name keeps it grounded.
More names to explore
Questions parents ask
Are rare celestial boy names always statistically rare?
Not necessarily. Style and measurable popularity are different. Each name card shows the exact-spelling 2025 U.S. count when the Social Security Administration published one.
Does a missing 2025 count mean nobody used the name?
No. The national public file omits names recorded fewer than five times for a sex in a year, so a missing count can mean zero or one to four births.
Should I avoid a name if it is rising?
Not necessarily. Popularity is only one part of choosing a name. Sound, family meaning, cultural fit and how the full name works matter more than chasing the lowest possible rank.
Will the same name be equally rare outside the United States?
No. Popularity varies by country, region, language and community. The figures on this site describe U.S. national data unless a page says otherwise.