Ascendant

Ascendant is an Effect-first TypeScript library for sidereal astrology. Start by calculating D1 and D9 for a UTC moment and location. The result contains shared Placements and cusp-aware Charts that you can reuse with the other calculation modules.

Install

bun add astro-ascendant effect@rc

1. Import the packages

This example uses Bun, KrishnamurtiVP291 ayanamsa, and Placidus houses (AstroParams.DefaultAstroParams).

import { BunRuntime, BunServices } from "@effect/platform-bun";
import { AstroParams, Chart, Swisseph } from "astro-ascendant";
import { Console, DateTime, Effect, Layer } from "effect";

2. Create the runtime layer

const runtimeLayer = Layer.mergeAll(
  BunServices.layer,
  Swisseph.SwissephLayer,
  AstroParams.DefaultAstroParams,
);

runtimeLayer provides the Bun services, Swiss Ephemeris implementation, and default astrological parameters at the root of the program.

3. Create the chart input

const input = Chart.ChartParams.make({
  moment: Chart.Moment.make({
    date: DateTime.makeUnsafe("2000-01-01T12:00:00.000Z"),
  }),
  latitude: 12.9716,
  longitude: 77.5946,
  sex: "Male",
});

ChartParams combines a UTC Moment with latitude, longitude, and optional birth sex.

4. Generate D1 and D9

Chart.generate always returns D1 first. Passing [9] adds the D9 divisional chart.

const examples = Chart.generate(input, [9]).pipe(Effect.provide(runtimeLayer));

5. Print the results

Use Console.table to inspect the shared placements and generated charts:

const examplesWithOutput = examples.pipe(
  Effect.tap((calculation) =>
    Effect.gen(function* () {
      yield* Console.log("Placements");
      yield* Console.table([
        {
          Point: calculation.placements.lagna.name,
          Longitude: calculation.placements.lagna.longitude,
          Retrograde: "—",
        },
        ...calculation.placements.planets.map((planet) => ({
          Point: planet.name,
          Longitude: planet.longitude,
          Retrograde: planet.is_retrograde,
        })),
      ]);
      yield* Console.log("Charts");
      yield* Console.table(
        calculation.charts.map((chart) => ({
          Division: `D${chart.division}`,
          HouseSystem: calculation.astroParams.houseSystem,
          Ayanamsa: calculation.astroParams.ayanamsa,
        })),
      );
    }),
  ),
);

6. Run the program

BunRuntime.runMain(examplesWithOutput);

calculation.placements contains the shared sidereal positions. Reuse it with the Dasha, Ashtakavarga, and Jaimini calculators.

Getting started