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 observatory location, sky location or WCS, and band or filter). All uploads will be required to accept a CC BY-SA or similar license that enables public sharing and reuse of all submitted data products. Trailblazer does not yet have plans for identifying linear features, matching satellite IDs to observed streaks, or measuring streak brightnesses.

Assembling a standardized dataset will enable these kinds of studies and inform more coordinated and planned observations and will better enable “dodging” or avoiding large numbers of satellites in certain situations. Planned observations of satellites are important to improve models, simulations, and satellite forecasting software, while avoidance includes preventing telescopes (both optical/NIR and radio) pointing in the direction of known satellites as well as determining retroactively if an observation suffers from satellite contamination.

1.2.2. Other satellite-impacted data in SatHub Astronomical Data Repositories

Trailblazer does not address all needs, including wavelengths outside visible/NIR, non-image data products, observations without a valid WCS, or file formats other than FITS (e.g., visual sightings or DSLR images). These kinds of observations also contain valuable information for characterizing satellite constellation populations and monitoring them over time. For example, preliminary studies (e.g., Tregloan-Reed et al., 2021) show that satellites darkened to meet the 7th V magnitude target from the SATCON1 Report tend to be significantly brighter in the NIR, but there are presently insufficient observations in other bands to write more specific darkening requirements for operators.

We propose that any new collection of images or data products affected with signatures of LEOsats coordinate with the existing satellite tracking community and make all data publicly accessible. A need exists for at least the collections outlined below.

1.2.2.1. Radio data affected by satellites

Radio observations are significantly impacted by emissions from satellites (see, e.g., the D&QS Report). Data products to collect may include FITS files/images, u,v interferometric data, time-ordered data, etc. Files should come with valid metadata to make it clear at which telescope, pointing direction, observing mode, and frequencies it was recorded. These may represent examples of ongoing interference from satellites, or transient events that have unknown sources. Ideally it would be known that the interference present in the data is caused by satellites, rather than terrestrial interference sources, but it is not always possible to guarantee this. When designing a campaign to collect impacted radio data, it is important to keep in mind that significant interference can occur at frequencies that satellites don't intentionally transmit at, because signals can be caused out-of-band by electronics on the satellite or poor filters for transmissions.

Radio astronomers may wish to gather information on bandwidth and time lost due to high power events (satellite crossing the main beam of a radio observatory) as well as residual radio frequency interference or signals originating in the side lobes of a radio observatory. We note that above frequencies of about 10 Rh