Nicheloom

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An open source astronomy dashboard (https://caelus.siderealcode.net)

Details

External ID
45876401
Source
HN
Company
—
Product
—
Website domain
—
Launched
Nov. 10, 2025
Cohort
—
Upvotes
5
Upvotes percentile
0.0982532751091703
Tags
—
Fetched at
Sept. 7, 2026, 9:25 p.m.
Updated at
Sept. 7, 2026, 9:25 p.m.

Description

Hello HN! My name is Rémy and I recently published an astronomy dashboard where everything is open source: the code of the website, the framework it is based on and the library that computes astronomical data.For the last few years, I have been developing the Ruby library Astronoby (https://github.com/rhannequin/astronoby) with as much dedication and perseverance I could while I don't have any scientific academic background. My end goal was to use this library and build a website that not only provides as much data as possible, but let anyone access and understand how it was computed. This goal is on its was of completion with Caelus.Of course the website is still quite new and there are many features I will implement in the coming weeks and months, including the ability to set any date, having a global view of the Solar System, having an interactive sky chart, a tool to prepare your observation night, having the website in multiple languages, etc.I believe astronomical data should be universal and anyone should be allowed to easily access this data, manipulate it, understand how it was generated, and contribute to and with the community.My goal is to make this project truly collaborative. I am open to feedback, ideas, requests, bugs, everything, to offer the community open source astronomical data.Thank you all.Website: https://caelus.siderealcode.netSource code: https://github.com/rhannequin/caelus

Enrichment

Theme
astrology, spirituality, and lifestyle tools
Vertical
Horizontal
Function
Dev tools
Audience
Developer
AI stance
Not AI
Project type
Hobby / open-source project
Normalized one-liner
open source astronomy dashboard
Manually corrected
False

Could you build this?

Partial The web dashboard and visualizations can be easily vibe-coded, but high-precision astronomical calculations require specialized celestial mechanics algorithms and ephemeris tables.

What it would actually take: The front-end can be built with React/Next.js and charting/planetarium canvas libraries, but the backend requires precise astronomical calculation engines (like VSOP87, ELP2000, or SPICE kernels) to calculate ephemerides, celestial coordinates, and nutation/precession corrections. A developer must either implement or integrate complex celestial mechanics libraries and maintain reliable time standard conversions (UTC, TAI, TT).

Discussion

3 comments analyzed.

Competitors mentioned: Swiss Ephemeris, JPL Development Ephemeris (DE), IMCCE INPOP

Concerns raised: Data not particularly new/current

Competitors

Other products that read as similar to this one — 114 launches clear the similarity bar, closest 8 shown.

Attention rank: #114 of 115 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).

Looks like the first mover among its competitors.

Other launches for this product

Same idea, different domain

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