How to open .FITS files on Android
To open .FITS files on Android, android typically lacks standard FITS support in default viewers; for reliable viewing/analysis, move the file to a desktop and open it with DS9 or Python/Astropy.
Step-by-step instructions
- Android typically lacks standard FITS support in default viewers; for reliable viewing/analysis, move the file to a desktop and open it with DS9 or Python/Astropy.
Common issues
The file won’t open in my normal photo viewer
FITS is a scientific data format and is not broadly supported by consumer image apps, even though it can store images.
- Open it with a FITS-capable viewer such as SAOImage DS9.
- If you need to process the data, use Python with astropy.io.fits to read the HDUs and extract the image array.
Opens, but looks black/blank or the contrast is wrong
Astronomical FITS images often contain high dynamic range data, non-8-bit pixel types, or values that require scaling/stretching to display properly.
- In a FITS viewer (e.g., DS9), adjust the display scale/stretch (common for astronomical images).
- Check the header keywords and data type by reading the file with astropy.io.fits to understand scaling and value ranges.
Error reading FITS: corrupted/truncated file or invalid header
FITS readers expect a strict structure (HDU headers and data blocks). Interrupted downloads or partial transfers can break that structure.
- Re-download or re-copy the file from the original source and compare file sizes if possible.
- Try opening with another FITS reader/library; many tools rely on CFITSIO, which may provide clearer error messages.
- If you have access to the producer software/instrument pipeline, regenerate or re-export the FITS file.
The FITS file has multiple extensions and I can’t find the image/table I need
A single FITS file can contain multiple HDUs (primary HDU plus extensions like images or tables). Some viewers open only the first HDU by default.
- In DS9, browse/select different extensions (HDU list) to view the desired image/plane.
- In Python, use astropy.io.fits to list HDUs and select the correct extension by index or name.
Still can’t open your .FITS file?
Recover a deleted or lost .FITS file
If the file was deleted by mistake or the drive was formatted, data recovery software may be able to get it back. Stop writing to that drive right away, because new data can overwrite what you want to recover.
Windows software that recovers deleted or lost files from PCs and external drives such as HDDs, SSDs, USB drives and memory cards, after deletion, formatting or a crash.
Wondershare RecoveritWindows and Mac software that recovers deleted or lost files from computers and external drives such as HDDs, SSDs, USB drives and SD cards.
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Security note
FITS files are data files (headers + data blocks) and do not typically contain active content like macros, but they can still be risky if opened with vulnerable parsers—use well-maintained tools and libraries (e.g., established FITS viewers and Astropy/CFITSIO-based readers).