ONE SKY · SEVERAL CONVENTIONS
Change the reference.
Keep the trace.
Compare a tropical calculation and an explicit sidereal reading. The calculated sky stays the same; the chosen division and the symbolic texts are distinct. With a declared place, the ascendant and the houses are added to the calculation. No predictive cycle.
Start with a calculation
Enter a known date, time and time zone: ten positions are calculated on your device. You can also import a trace from the existing engine or explore the fictional example; the place and context of an imported trace are not carried over.
Unknown time: no instant is assumed. The offset applied is shown for checking; the historical daylight saving time rules are those of your browser.
No calculation loaded.
Which perspective would you like to compare?
Lahiri and Fagan–Bradley: single-point comparison available only for the fictional example of 1 January 2000 at 12:00 UTC. Neither extrapolation to births nor a complete traditional chart. The readings below are the same original leads applied to the selected sign; they do not reproduce a Vedic or Western school.
Ascendant and houses · optional
Enter the coordinates of the place corresponding to the instant shown, in decimal degrees: north and east positive, south and west negative. Without a place, only the longitudes are shown.
Search for a city to fill in the latitude, longitude and time zone in one go, or enter the coordinates by hand.
Twelve equal signs, anticlockwise; the numbers on discs refer to the table. Without a place: 0° Aries on the right. With a place: ascendant on the left, numbered house cusps at the centre.
| Body | Tropical | Selection | House | Astronomical constellation |
|---|
| House | Cusp | Bodies |
|---|
Aspects between the bodies
Orbs used: 8° for the conjunction and the opposition, 6° for the square and the trine, 4° for the sextile. Ascendant and Midheaven are included when a place is declared.
| Bodies | Aspect | Orb | Symbolic reading |
|---|
No aspect within the orbs used.
Today’s sky against this chart
These contacts describe a geometry of the sky; they do not announce any event.
| Bodies | Aspect | Orb | Symbolic reading |
|---|
Conventions and limits
Local computation: Astronomy Engine 2.1.19 by Don Cross, MIT licence retained in the code. Source of the stellar reference: ICRS J2000 coordinates of Spica, SIMBAD/CDS catalogue. UTC–TT conversion: IERS table, validity and limits stated in the check file.
The stellar reference fixes Spica at 180° in the sidereal zodiac. J2000 catalogue coordinates, without propagation of the star’s proper motion: this educational mode is neither a Lahiri nor a certified Fagan–Bradley implementation. A manual ayanamsa must match the displayed instant.
H9 multiplies longitudes by nine modulo 360. It is not a complete Vedic Navamsha chart. Astronomical constellations are not the twelve 30° signs.
Ascendant and houses: calculated only for a declared place, latitudes up to ±66°, in Placidus, Equal houses or Whole signs; results checked against Swiss Ephemeris 2.10.03 over 720 cases, difference below 0.01°. An error in the time or time zone shifts the Ascendant strongly. House placement by ecliptic longitude.
City list: city-timezones 1.3.4, MIT licence, bundled with the site; coordinates rounded to a hundredth of a degree.
Aspects and today’s sky: geometry calculated locally, with no forecast. Readings written from traditional associations. No demonstrated predictive value. Original reading assembled locally, with no AI interpreting private information.
Local processing, state kept in memory only. A download stays on your device; the site’s connection logs are separate. No payment.