Ephemeris MCP vs HelioSPICE
A side-by-side look at the Ephemeris MCP 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 Ephemeris MCP 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 Ephemeris MCP when
- You need dedicated capabilities in the Aerospace & Astrodynamics domain.
- You prefer a local stdio subprocess transport.
- You want tools like
get_planetary_positions.
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 | 49/100 · Fair | 47/100 · Fair |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Local subprocess (stdio) |
| Auth | Not declared | Not declared |
| Pricing | Not declared | Not declared |
| Required env vars | None listed | XHELIO_SPICE_KERNEL_DIR |
| Verified owner | Community listing | Community listing |
| GitHub stars | 4 | 0 |
| Directory activity | 1 views 0 installs 0 upvotes | 0 views 0 installs 0 upvotes |
| Tools | 1 | 6 |
| Full listing | View Ephemeris MCP | View HelioSPICE |
Tools & capabilities
Ephemeris MCP tools 1
get_planetary_positionsReturns precise Tropical Zodiac positions for all planets, Sun, Moon, and chart angles.
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.
Ephemeris MCP
{
"mcpServers": {
"ephemeris-mcp": {
"command": "uvx",
"args": [
"ephemeris-mcp"
]
}
}
}
HelioSPICE
{
"mcpServers": {
"heliospice": {
"command": "uvx",
"args": [
"xhelio-spice"
],
"env": {
"XHELIO_SPICE_KERNEL_DIR": "YOUR_XHELIO_SPICE_KERNEL_DIR_HERE"
}
}
}
}
Frequently asked questions
Ephemeris MCP is categorized under Aerospace & Astrodynamics and uses a local stdio subprocess. HelioSPICE belongs to Aerospace & Astrodynamics and uses a local stdio subprocess. Pick Ephemeris MCP 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.
Ephemeris MCP has no declared pricing — check the project's own site. 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 ephemeris-mcp and heliospice as separate keys in the same mcpServers object, and your assistant will call tools from either one.
On AllMCPs, Ephemeris MCP has a quality signal of 49/100 (Fair) with 1 views, 0 installs and 4 GitHub stars. HelioSPICE has 47/100 (Fair) with 0 views, 0 installs and 0 GitHub stars.