How it's made
How a sky is made
A Celestial Portrait is a calculation before it is a picture. This is what happens between the moment you type and the print on your wall, and the sources behind it.
How a sky is made
One minute, in universal time
You give us a local date, a time and a place. We convert the local time to universal time using the IANA time-zone database, including the summer-time rules that applied in that place in that year. If the clocks went back and a time happened twice, or went forward and a time never happened, we ask you to check it instead of guessing.
The planets, from NASA JPL
The Sun, the Moon and the planets are computed with DE440s, the planetary and lunar ephemeris published by NASA's Jet Propulsion Laboratory, through the Skyfield astronomy library. We place them as they appeared from that point on Earth, at that minute.
The stars, from Hipparcos
Every star down to magnitude 5.6 comes from the European Space Agency's Hipparcos catalogue, at its apparent position for that night. Brightness sets each star's size and glow; nothing is scattered for effect, and no star is added.
Your horizon as the rim
The sky is projected from the point straight above you, with north at the top and east on the left, as it looks when you lie back and look up. The edge of the circle is your horizon. Constellation lines join real catalogue stars, and the Milky Way is modelled from its true galactic position.
Art around the facts
The watercolour wash and the paper texture are artistic layers, made once and set behind the sky. The calculated sky, the gold bezel and every line of text are drawn on top as precise vectors, never generated or retouched.
A certificate with every print
Each portrait comes with a three-page Astronomical Certificate & Sky Guide: the moment in universal time, the positions of the Sun, Moon and planets, the Moon's phase, how to read your map, notes on any uncertainty, the data sources and the print's own fingerprint.
The Celestial Portrait
The certificate, page by page
Every print comes with a three-page Astronomical Certificate & Sky Guide: the moment in universal time, the positions of the Sun, Moon and planets, the Moon's phase, and how to read your map.
If you don't know the time
We never pretend. Without a time there is no true horizon, so the print becomes a date edition: a chart centred on the Sun with the Moon's path across that day, and no rising sign.
And the readings
Your natal chart uses the same principle: positions computed for your minute and place, tropical signs and whole-sign houses. Aurora, Astralixa's digital astrologer, writes only from those computed facts, and every text is checked against your chart before you see it.
Sources
- NASA JPL DE440s planetary and lunar ephemeris (Park et al., 2021, The Astronomical Journal 161:105)
- ESA Hipparcos Catalogue (ESA 1997, SP-1200)
- Skyfield astronomy library (Brandon Rhodes)
- IANA time-zone database
- Constellation figures from d3-celestial (Olaf Frohn)
- Natal charts: Astronomy Engine (Don Cross)
Astrology and crystal content is symbolic and for entertainment purposes only. It does not predict events and is not advice.