Real astronomy, five sciences, two roles.
Astra Atlas computes every result from the actual positions of the planets. Three of these sciences map where your life leans across the Earth. Two tune that map to you, setting how loudly each place speaks. Here is what powers your map and how we hold ourselves to real numbers.
Read this first. Astra Atlas is for reflection and entertainment. It is not medical, financial, or life advice, and nothing here predicts your future or tells you what to do.
The astronomy is real and precise. The meanings people draw from it are a tradition and a lens, offered so you can think, not so you can obey.
Tropical natal chart
Your natal chart is the arrangement of the Sun, Moon, and planets at the moment and place you were born, read in the tropical zodiac. Tropical means the zodiac is anchored to the seasons, to the equinoxes and solstices, which is the frame most of the Western world reads by.
From your date, time, and birthplace we place every body in the sky and work out the houses and angles. This is one of the two readings that tune the map to you, weighting how loudly each place speaks. Everything else on the map is built on this foundation.
Astrocartography
Astrocartography maps where each planet was directly overhead, rising, setting, or at the lowest point, drawn as lines across the surface of the Earth. Ten bodies across four angles give forty lines in total.
Where you stand relative to those lines is the heart of the idea that a place can carry a different feeling of the sky for you than the place next door. It is one of the three readings that map where your life leans across the Earth.
Local Space
Local Space reads the sky as compass bearings from a single point on the ground, your birthplace. Each planet points in a direction, an azimuth, that you can follow across a map.
It is a close in companion to astrocartography, another of the three readings that map where your life leans: instead of lines wrapped around the globe, it gives you directions to travel from where you began.
Vedic (sidereal)
The Vedic system of India reads the sky against the fixed stars rather than the seasons. We use the Lahiri ayanamsa to shift into the sidereal zodiac, then add the nakshatras, the twenty seven lunar mansions.
On top of that sits the Vimshottari dasha, a timeline of planetary periods, and the lunar nodes Rahu and Ketu, whose lines are the third reading that maps where your life leans across the Earth. Together they give a second, independent reading of the same birth moment.
Bazi (Four Pillars)
Bazi, the Chinese Four Pillars of Destiny, expresses your birth as four pairs of elements drawn from the year, month, day, and hour. It is a different language for the same instant in time.
From the pillars it also reads a two sided directional lean, favorable one way and less so the other. With the natal chart it is one of the two readings that tune the map to you, adjusting how loudly each place speaks rather than drawing new lines.
Computed from real astronomical data.
Your positions are computed from real astronomical data, the same kind working astronomers rely on.
Under the hood we use Skyfield, an open source astronomy library, reading the public NASA/JPL DE440s planetary ephemeris. This is the same class of data professional astronomers use to point telescopes and plan missions. It is published openly by NASA and the Jet Propulsion Laboratory. Using public data is not a partnership, and it is not an endorsement of Astra Atlas by NASA or the Jet Propulsion Laboratory.
We hold the engine to a set of golden tests, reference cases checked against independent calculations. Across those tests our planetary positions agree to within a fraction of an arcsecond, far finer than anything that would change where a line falls on your map.
That is the whole promise. The numbers are honest. From real astronomy, not guesswork. What you do with the reflection is yours. See the full disclaimer.