Redshift is an important concept in astrophysics that describes how the light from distant objects is shifted to longer wavelengths as they move away from the observer. This effect is most commonly associated with the expansion of the universe, where distant galaxies move away from us, causing their emitted light to be redshifted.
In the scenario you described, you have a distant space object that is initially in a "stationary" frame of reference relative to the observer (scientist). If this object remains stationary in a local frame (or is relatively unchanged in its motion), the observer would not observe a redshift in its spectrum. The key points to consider are:
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Redshift from Motion: Redshift occurs when there is relative motion between the light-emitting source and the observer. If the distant object is moving toward the scientist, it will actually exhibit a blueshift (where the wavelengths are compressed and appear shifted toward the blue end of the spectrum) rather than a redshift.
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Stationary vs. Moving: If the object were stationary relative to the scientist and not moving away, the light it emits would retain its original wavelength, and no redshift (or blueshift) would be observed.
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Cosmological Redshift: If the object is very far away and is part of the expanding universe, even if it is not moving toward or away from the observer, the overall effect of cosmic expansion can cause us to observe redshift due to the expansion of space itself, shifting the light to longer wavelengths.
Thus, if you want to observe redshift in the spectrum of a distant space object, it typically involves either that object moving away from the observer (increasing distance) or the effects of the expanding universe, rather than it moving toward the scientist or being stationary.
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