Astronomy MCP Server vs HelioSPICE
A side-by-side look at the Astronomy MCP Server and HelioSPICE MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.
Verdict: choose Astronomy MCP Server for aerospace & astrodynamics work as a local process; choose HelioSPICE for aerospace & astrodynamics as a local process. You can also run both side by side in one mcpServers block.
Which MCP server should you choose?
Choose Astronomy MCP Server when
- You need dedicated capabilities in the Aerospace & Astrodynamics domain.
- You prefer a local stdio subprocess transport.
- Its auth model fits you: No auth required.
- You have the keys it needs:
ASTRONOMY_ENABLE_HORIZONS. - You want tools like
astronomy_get_sky_position, astronomy_get_rise_set, astronomy_get_moon_phase.
Choose HelioSPICE when
- You need dedicated capabilities in the Aerospace & Astrodynamics domain.
- You prefer a local stdio subprocess transport.
- You have the keys it needs:
XHELIO_SPICE_KERNEL_DIR. - You want tools like
get_ephemeris, compute_distance, transform_coordinates.
Feature & specification comparison
Rows where the two servers differ are marked.
| Spec | ||
|---|---|---|
| Category | Aerospace & Astrodynamics | Aerospace & Astrodynamics |
| Quality signal | 55/100 · Good | 47/100 · Fair |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Local subprocess (stdio) |
| Auth | No auth required | Not declared |
| Pricing | Free | Not declared |
| Required env vars | ASTRONOMY_ENABLE_HORIZONS | XHELIO_SPICE_KERNEL_DIR |
| Verified owner | Community listing | Community listing |
| GitHub stars | 3 | 0 |
| Directory activity | 3 views 0 installs 0 upvotes | 0 views 0 installs 0 upvotes |
| Tools | 7 | 6 |
| Full listing | View Astronomy MCP Server | View HelioSPICE |
Tools & capabilities
Astronomy MCP Server tools 7
astronomy_get_sky_positionApparent position of one body or named star: RA/Dec, alt/az, ecliptic, magnitude, phase, Sun elongation, constellationastronomy_get_rise_setRise, set, and transit times for a body, plus civil, nautical, and astronomical twilight for the Sunastronomy_get_moon_phaseIlluminated fraction, phase name, synodic age, and the next four quarter phasesastronomy_find_eventsNext eclipses, equinoxes, solstices, moon quarters, oppositions, conjunctions, greatest elongations, or apsidesastronomy_list_visibleWhat's up now: naked-eye bodies (and optional bright stars) above the horizon, ranked, with a sky-condition gateastronomy_get_ephemerisSmall-body or spacecraft ephemeris from JPL Horizons (opt-in)astronomy_get_satellite_passesVisible satellite passes from a CelesTrak element set propagated with SGP4 (opt-in)
HelioSPICE tools 6
get_ephemerisPosition/velocity — single time (inline) or timeseries (CSV)compute_distanceDistance between two bodiestransform_coordinatesCoordinate frame transformlist_spice_missionsSupported missionslist_coordinate_framesAvailable frames with descriptionsmanage_kernelsKernel cache management
Ready-to-paste client configs
Paste either block (or both) into your client config, e.g. claude_desktop_config.json or ~/.cursor/mcp.json. We only show a config when the install command is confirmed.
Astronomy MCP Server
{
"mcpServers": {
"astronomy-mcp-server": {
"command": "bunx",
"args": [
"@cyanheads/astronomy-mcp-server@latest"
],
"env": {
"ASTRONOMY_ENABLE_HORIZONS": "YOUR_ASTRONOMY_ENABLE_HORIZONS_HERE"
}
}
}
}
HelioSPICE
{
"mcpServers": {
"heliospice": {
"command": "uvx",
"args": [
"xhelio-spice"
],
"env": {
"XHELIO_SPICE_KERNEL_DIR": "YOUR_XHELIO_SPICE_KERNEL_DIR_HERE"
}
}
}
}
Frequently asked questions
Astronomy MCP Server is categorized under Aerospace & Astrodynamics and uses a local stdio subprocess. HelioSPICE belongs to Aerospace & Astrodynamics and uses a local stdio subprocess. Pick Astronomy MCP Server for aerospace & astrodynamics work and HelioSPICE for aerospace & astrodynamics.
Copy the mcpServers block from the config section on this page into your client's config (for example claude_desktop_config.json or ~/.cursor/mcp.json), then fully restart the client.
Astronomy MCP Server is listed as free. Auth: no auth required. HelioSPICE has no declared pricing — check the project's own site. If a server needs environment variables such as API keys, define them under the env key in your client's MCP config.
Yes. MCP clients support multiple servers: add astronomy-mcp-server and heliospice as separate keys in the same mcpServers object, and your assistant will call tools from either one.
On AllMCPs, Astronomy MCP Server has a quality signal of 55/100 (Good) with 3 views, 0 installs and 3 GitHub stars. HelioSPICE has 47/100 (Fair) with 0 views, 0 installs and 0 GitHub stars.