For experienced users who already own a Raspberry Pi 4 or 5 unit, StellarMate OS is a complete software package ready for deployment on your Raspberry Pi. It is provided as a compressed OS Image file (.img.xz) that you can burn to an SD card and fire it up immediately to enjoy the full benefit of StellarMate software stack. The following packages are included in addition to the base OS:

• INDI
• KStars/Ekos
• PHD2
• Astrometry.net with index files.

Requirements

• Raspberry PI 4/5 with 4GB RAM or higher. Raspberry PI3 is not supported.
• A 32GB+ Class 10 MicroSD card is highly recommended.
• If using a DSLR camera, then you must first ensure the camera is supported before you proceed.

A 3A+ 5v power supply for Raspberry PI 4 and 5A+ 5v power supply for Raspberry PI 5 is required in order to properly operate StellarMate OS on Raspberry Pi 4/5. Using anything less than specified amperage would result in system instablities and possible corruption. Invest in a reputable power supply before you boot StellarMate OS.

Download

After your purchase, you will receieve a link in the email to download the image files. We offer two installation images depending on where you want to install to.

1. Install to Rasbperry PI SD Card

Since the file size is ~6.2 GB, it is highly recommended to use a dedicated download manager to download the file. After you download the file appropiate for your Raspberry Pi version, you can verify its integrity by computing its hash. Use Quick Hash GUI to verify the integrity of the image file. There are two files available for download:

• File: StellarMateOS_2.1.1_RPI.img.xz
• SHA256: 33b4c5d709f320f2cef4b1b2e21b8a6ac8e4029ddcce13005f0526ca32adff54

Raspberry PI Imager is a graphical SD card writing tool that works on Mac OS, Linux and Windows, and is the easiest option for most users. It supports writing images directly from the zip file, without any unzipping required. To flash SM OS image:

Do not customize any settings using Raspberry PI imager. Flash the image as-is without making any changes to the image otherwise it may fail to start.

• Download Rasbperry PI Imager and install it.
• Connect an SD card reader with the SD card inside.
• Open Raspberry PI Imager and select from your disk the downloaded StellarMate .xz image.
• Select the SD card you wish to write your image to.
• Click WRITE to begin writing data to the SD card.

2. Install to Rasbperry PI NVMe Disk

The Raspberry Pi NVMe image is designed for installation on Raspberry Pi devices equipped with NVMe disks. This installation method uses a graphical installer and requires a monitor, keyboard, and mouse.

Download:

• File: StellarMateOS_2.1.1_RPI_NVME.img.xz
• SHA256: 69f2e73142980ee91945f1d54fed6b1d6d44adf5d2c5f22dead621e8285cadf3

Flash the image to a USB drive or SD card (minimum 16GB) using Raspberry Pi Imager following the steps outlined above

Boot Order (if NVMe already has a bootable OS):

If an older OS is already installed and bootable on your NVMe disk, you must change the boot order to prioritize USB boot:

Set BOOT_ORDER=0xf164 then save and exit.

Installation:

• Using a USB drive: Remove any SD card from the Raspberry Pi, insert the USB drive, and power on
• Using an SD card: Remove all USB devices, insert the SD card, and power on
• Make sure the LAN cable is unplugged.

The graphical installer will load automatically. Follow the on-screen prompts to select your NVMe disk as the installation target. Once installation completes, remove the installation media (USB drive or SD card) and reboot.
If you need to download StellarMate OS again in the future, make sure you are logged in to the stellarmate.com website and then go to the Orders page. You should see a list of  your orders. Click on your order link, then scroll down to see the downloads. Make sure to download the SM OS version appropiate for your hardware platform.

Boot up

Once the image is burned to the card, insert the microSD card into Raspberry PI 4/5 and power it up.

Note: StellarMate can take up to 2 minutes before switching to HotSpot mode on first startup. By default, StellarMate runs on 5 Ghz WiFi. Your phone/tablet must support 5Ghz WiFi in order to connect to StellarMate. It is possible to configure StellarMate to run on 2.4Ghz afterwards, but it is not recommended.

Passwords

• The default StellarMate OS password is smate
• The default StellarMate WiFi HotSpot password is stellar@mate

Learning StellarMate

For new users, using StellarMate effectively can take a bit of a learning curve (like everything else) especially given the breadth of the features if provides. Here are some useful resources to get your started:

• First Time Setup tutorial.
• StellarMate Video tutorials.
• Ekos Video Tutorials.

What's new with SM OS 2.0?

1. Atomic Updates

Updates are delivered as complete, tested packages that are applied all at once—ensuring your entire system stays consistent. Delta updates mean only the changes are downloaded, saving bandwidth. If an update causes any issues, you can easily rollback to a previous version from the StellarMate App or StellarMate Tools. Perfect for remote setups where reliability is critical.

2. Integrity Checks

A service runs at every startup to verify all system files are intact and in working order. If any corruption or issues are detected, the system automatically recovers to ensure you always boot into a fully functional state. Your observatory stays reliable without manual intervention.

3. Native NVMe & SD Card GUI Installer

The new graphical installer makes setup effortless whether you're setting up a Raspberry Pi, Mini PC, or StellarMate Controller. Just follow the clear on-screen prompts—the installer handles all the technical details automatically. Installation is now point-and-click simple across all platforms.

4. Rolling OS with Latest Updates

Your system continuously receives the latest drivers for WiFi, cameras, mounts, and other peripherals without waiting for major OS releases. No more reinstalling a completely new OS every two years like with the old Debian-based system. Security updates, performance improvements, and new hardware support

5. Snapshots and Rollbacks

The system automatically saves its state before updates and configuration changes. If something doesn't work right, simply select a previous snapshot from the StellarMate App or StellarMate Tools to instantly restore your system to a working state. Experiment freely knowing you can always undo changes with ease.

Support

We are proud to offer top-notch support for our customers. Please make sure to check out the Frequently Asked Questions and Tutorial articles first. To report any issues with StellarMate or Ekos, please submit a ticket, and our support team will get back to you as soon as possible. Please make sure to submit the relevant logs to aid in diagnosing and resolving the issue efficiently.

Release History

•  
• v2.1.1 Release 2026-04-09
  • KStars 3.8.2 and INDI 2.2.0
  • Bug fixes and performance improvements.
• v2.0.1 Release 2026-03-18
  • Fixed bluetooth and GPS startup.
  • GAIA based astrometry files.
• v2.0.0 Release 2026-02-08
  • New StellarMate OS based on Arch Linux
  • KStars 3.8.1 & INDI 2.1.8 Flatpak