External Control
AstroHelm can act as a telescope that external software connects to. Once linked, your planetarium or imaging application can display the current pointing position and send GoTo commands.
To connect two nearby iPhones or iPads running AstroHelm, see Remote (iOS).
How It Works
Section titled “How It Works”AstroHelm presents itself as a telescope using ASCOM (Alpaca), INDI, and LX200 on both iOS and Android. The iOS version also supports the Stellarium protocol. External software can read the current coordinates and send GoTo targets. When a GoTo command arrives, AstroHelm displays the target on screen so you can manually slew to it using the onscreen directions.
Enabling the Server
Section titled “Enabling the Server”- Open Settings → External Control and toggle on the switch.
- Note the IP address and port shown beneath the toggle. The IP address is the four numbers separated by dots before
:(for example,192.168.1.123), and the port is the four or five digits after:. Enter both in your client application.
Networking
Section titled “Networking”Using Another App on the Same Android Phone
Section titled “Using Another App on the Same Android Phone”On Android, enabling External Control keeps plate solving and the telescope servers running in the background while you use another astronomy app, such as SkySafari or Stellarium Mobile. Keep the screen on: plate solving and external control pause when the screen turns off. You can stop External Control from its notification or from AstroHelm’s settings.
Connecting Devices
Section titled “Connecting Devices”All servers run over Wi-Fi. Your smartphone running AstroHelm (the server) and your device running external software (the client) must be on the same local network. A home network typically satisfies this requirement, but for field use it may not be practical.
There are a few alternatives:
Mobile Hotspot
Section titled “Mobile Hotspot”If your observing site has cellular coverage, you can enable a mobile hotspot to put both devices on the same network.
- Client hosts the hotspot, server connects to it: Proceed as usual.
- Server hosts the hotspot, client connects to it: AstroHelm may not detect the correct IP address automatically. For an iPhone hotspot, try
172.20.10.1first. Android hotspot addresses vary by device. On the client, open the connected Wi-Fi network’s details and look for the Router or Gateway address — that is the server’s IP address.
Portable Router
Section titled “Portable Router”A portable router lets you run your own network in the field. Popular options include GL.iNet and UniFi.
Personal VPN
Section titled “Personal VPN”If both devices can reach the internet, a personal VPN lets them communicate across different networks. Tailscale is a popular free option.
Client Setup
Section titled “Client Setup”SkySafari
Section titled “SkySafari”SkySafari supports two modes: Go-to and Push-to. In Go-to mode you get slew controls (which have no effect on AstroHelm) and can send GoTo targets to AstroHelm. Push-to mode simply shows the current position. Use whichever mode suits your workflow — both read coordinates identically.
For Go-to mode, you can use ASCOM, INDI, or LX200 protocol.
For Push-to mode, create a telescope preset using “Other”. Choose either Equatorial Push-To or Alt-Az Push-To, depending on your mount. Choose Meade LX200 Classic as scope type.
Stellarium Mobile
Section titled “Stellarium Mobile”Stellarium Mobile uses the LX200 protocol. Under Observation Tools, enable Telescope Control and enter the LX200 IP address and port, then toggle the link on. You should see the reticle appear.
Note that telescope control requires the Plus version of Stellarium Mobile. Despite the name, Stellarium Mobile does not support the Stellarium protocol — use LX200 instead.
Stellarium Desktop
Section titled “Stellarium Desktop”In the plug-in manager, enable Telescope Control with Load at startup, then restart Stellarium. You can then add AstroHelm as a telescope using any protocol supported on your operating system.
To use the Stellarium protocol specifically with AstroHelm on iOS, select External software or a remote computer. For AstroHelm on Android, use ASCOM (Alpaca), INDI, or LX200, depending on what your Stellarium installation supports.
Coordinate systems: the Stellarium protocol uses J2000 coordinates; all other protocols use JNow.
Troubleshooting
Section titled “Troubleshooting”Client cannot connect
Section titled “Client cannot connect”- Confirm both devices are on the same Wi-Fi network. Some routers (especially public Wi-Fi) isolate clients - try disabling Client Isolation in your router settings.
- Verify the port number in the client matches the one shown in AstroHelm’s External Control settings.
- If your client supports multiple protocols, try switching to a different one.
Coordinates are wrong or stale
Section titled “Coordinates are wrong or stale”If your software has a refresh rate setting, try increasing it.