@almaobservatory/astro

An Angular library for astronomical-related calculations. Hard-core calculations. This has been populated with a simplified version of the ICRS <-> galactic converter from ATC's NgOTv1 and ESO's sexagesimal converter.

Shared between ngOT and SnooPI.

What's inside

• Coordinate math — sexagesimal ↔ decimal, sky / rest reference-frame conversions, offset → absolute via Euler rotation (SLALIB-style routines)
• Unit and value conversions — frequency, velocity, angle, sensitivity, flux, line-width, redshift
• ALMA reference data — receiver-band table (getReceiverBandByNumber) and the 7-octile atmospheric-transmission dataset (OctilesMap)
• Angular pipes — RaPipe, DecPipe, DurationPipe, DataSizePipe, FormatNumberPipe
• Utilities — solar-system targets, calibration-query helpers, rectangle / pointing geometry, formatters

The full public surface is in src/public-api.ts.

Installation

npm install @almaobservatory/astro

@almaobservatory/model is a peer dependency and will be installed alongside. lodash is also a peer dependency.

Usage

import {
  getReceiverBandByNumber,
  OctilesMap,
  offsetToAbsolute,
  RaPipe,
  DecPipe
} from '@almaobservatory/astro';

// Look up ALMA Band 6
const band6 = getReceiverBandByNumber(6);
console.log(band6.rfmin, band6.rfmax); // 211, 275

// Median atmospheric-transmission curve
const data = OctilesMap[4];

// Offset → absolute sky position (uses SkyCoordinates objects from model)
const result = offsetToAbsolute(
  { longitude: { value: 10, unit: 'arcsec' }, latitude: { value: 0, unit: 'arcsec' }, type: 'RELATIVE' },
  { longitude: { value: 86.8, unit: 'deg' }, latitude: { value: -70.7, unit: 'deg' }, type: 'ABSOLUTE' }
);

// Use pipes in standalone components
@Component({
  imports: [RaPipe, DecPipe],
  template: `{{ raDeg | ra }}, {{ decDeg | dec }}`
})

Development

The library lives under projects/astro/ in the ngOT workspace. From the workspace root:

# Build the library to dist/astro
ng build astro

# Build + run the consuming app against the latest local build
npm run build-all

ngOT's own code imports from astro (path-mapped to dist/astro); you do not need to publish to npm in order to consume changes inside ngOT.

Publishing a new version

When astro changes and external consumers (SnooPI, etc.) need to pick up the new version, publish a new release.

# 1. Bump the version in projects/astro/package.json
#    (patch / minor / major per semver)

# 2. From the workspace root:
npm run publish-astro

# 3. Verify
npm view @almaobservatory/astro

The publish script builds, runs fix-dist-pkg-astro to tidy the dist package.json, and runs npm publish --access public. Requires npm credentials for the @almaobservatory org.

License

ALMA Observatory.