The 'Phaser' of Star-Trek fame is far from, and has been far from fantasy already, for a long(ish) time.
Notice the time-lapse photo, with 'star-drift' in the sky. So it's an image taken in low light or at night over a number of minutes. In other words this 'X-Files' style "Kill-Switch" episode type, potential space-based weapon, would not be visible in use. Probably not in pitch darkness, and at full 'Blast' kids.'
In physics, a FASOR is an acronym for Frequency Addition Source of Optical Radiation. It is a device similar to a laser where the emitted light is produced in a sum-frequency generation process from two laser sources that operate at a different wavelength. The frequencies of the sources add directly to a summed frequency. Thus, if the source wavelengths are λ1 and λ2, the resulting wavelength is ... ...
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But the ubiquitous question remains: Why would we ever want to take such weapons to outer space?