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CycleCalcs Astronomy

by cyclecalcs.comversion 1.1.0i★ –iRuns in the cloud
Registry namecom.cyclecalcs/astronomy

Install

Overview

Description from the maker (original English)

Read-only astronomy calculations: sun, moon, planets, eclipses, twilight and star positions.

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

  • Connection: Runs in the cloud
  • Transport: Streamable HTTP
  • Category: Other
  • You need to fill in: Authorization

Install

Pick the AI app you use, then copy the settings.

Before you install

Values marked secret are keys to your account. Never share them or paste them into a chat.

You need

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

This address needs a key in a request header, which the add-connector menu cannot set. Use Claude Code, Cursor or VS Code instead.

Run this in your terminal

claude mcp add --transport http astronomy https://www.cyclecalcs.com/mcp --header 'Authorization: your-value'

Fill in the empty values before running it.

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "astronomy": {
      "url": "https://www.cyclecalcs.com/mcp",
      "headers": {
        "Authorization": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "astronomy": {
      "type": "http",
      "url": "https://www.cyclecalcs.com/mcp",
      "headers": {
        "Authorization": "your-value"
      }
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This address needs a key in a request header, which the add-connector menu cannot set. Use Claude Code, Cursor or VS Code instead.

Your choice stays on this device in a cookie; no account needed.

Values you fill in

  • Authorization secret HTTP header
    Optional. Without a key, tools work up to 50 calls a day per network address; a key raises the daily limit. Bearer YOUR_KEY, where YOUR_KEY is a CycleCalcs API key from RapidAPI (the Basic plan is fr…

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Tool names and descriptions exactly as the server reported them on Nov 8, 2026. The maker wrote them, not us; we show them as plain text.

  • astro_sky_today

    One-call snapshot of the whole sky for a place and moment: moon phase and illumination, which planets are up and worth looking at, the next eclipse, and (with a location) sun times. Reach for this first when the question is broad, like "what is in the sky tonight". For solar-day

  • astro_sun

    The complete solar day for one location: sunrise, sunset, solar noon, day length, civil, nautical and astronomical twilight boundaries, and explicit polar day/night status at high latitudes. Location required. For a series, send start and end (step is whole days, e.g. "1d" or "7d

  • astro_moon

    The Moon at an instant or as a daily series: phase name and angle, illuminated fraction, distance, apparent size, libration, bright limb, and the next quarter phases. A location adds rise/set and altitude. For a calendar of new and full moons use astro_moon_phases; for the Moon's

  • astro_moon_phases

    Every new moon, quarter and full moon in a window (or the next few from a date): each with its exact instant, distance, apparent size, supermoon classification under both competing definitions, traditional full-moon name, and any eclipse falling on it. Use for "when is the next f

  • astro_positions

    Exact positions for up to 20 bodies at an instant or over a time grid: right ascension and declination in both J2000 and of-date frames, ecliptic longitude and latitude, distance, and, with a location, altitude and azimuth with refraction stated per field. With a location the pos

  • astro_rise_set

    Rise, upper transit, set and lower transit for one body at one location, with an explicit status at extreme latitudes (circumpolar, never rises) instead of missing values. Accepts fixed radec targets. For the Sun specifically, astro_sun returns richer twilight structure; for posi

  • astro_eclipses

    Solar and lunar eclipses: the next or previous from a date, or all in a range, with type, magnitude, obscuration, Saros series and global geometry. A solar eclipse also carries a computed hybrid flag and, when central, the duration, path width and Sun altitude at greatest eclipse

  • astro_dark_window

    The genuinely dark, moonless observing window for a night: astronomical night intersected with the Moon being down, ranked across up to 62 nights with a trend. The right tool for "when should I stargaze / photograph the Milky Way / observe deep-sky objects". Location required. Fo

  • observing_windows

    Is tonight good for observing here, and when? The clear, dark windows of tonight, and of the next nights the hourly cloud forecast covers, for one place: astronomical night with the Moon down (or up, with moon "any"), under the MET Norway cloud forecast. The windows are the ones

  • astro_planet_board

    All eight planets in one call for a date and optional location: constellation, magnitude, apparent size, elongation from the Sun, morning or evening sky, retrograde state with the next station, rise/set, and a worth-looking-tonight assessment. The right tool for "which planets ar

  • astro_planet_events

    Dated planet events. For Mercury and Venus, the apparition cycle: inferior and superior conjunctions, greatest eastern and western elongations, peak brightness (a Venus-only event: Mercury's brightness peaks behind the Sun where it cannot be seen), and the rare transits across th

  • astro_find_place

    Resolve a place name to coordinates, region, country, IANA timezone and a stable place_id, or reverse-look-up the nearest places to a lat/lon. Results are GeoNames data (CC BY 4.0); the response carries the required credit in its attribution field, which must be preserved when re

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 9, 2026

  • ! Caution

    Maker matches the repo

    The registry lists no source repo, so we cannot match the publisher (cyclecalcs.com) to the code

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • ✓ Pass

    Endpoint responds

    Responded in 461 ms (HTTP 200)

  • – Not applicable

    Sign-in with OAuth

    No sign-in needed

  • ✓ Pass

    No hidden instructions in tool descriptions

    Read 12 tool descriptions and found no hidden instructions to the AI

Compared with others in Otheri

  • More stars than 0% of the other 18703 servers in this category
  • Published to the registry more recently than 54% of the other 18703 servers in this category
  • Basic checks equal to or better than 37% of the other 18703 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is CycleCalcs Astronomy safe?

It passed 2 of 3 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

You need to fill in: Authorization

Does it run on my computer or in the cloud?

It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.

Is it still maintained?

The GitHub repo last changed –, and the latest version (1.1.0) reached the registry 39 days ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.

What can I use instead?

In the same category: Spec Driven Development, Remote Desktop Commander, awardlanes

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README from the maker

No README found in the repo

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