For easy calculation, I chose an exactly 25% increase in wavelength, achievable if the cat is receding at 25 % of the speed of light.
Or vice versa for blueshift. For example, a low-pressure sodium lamp in old street lights is near-monochromatic at 589 nm (pale yellow), which will reach 678nm red at 15% redshift, while a CD infrared laser incoming at the same 0.15๐ speed will have the same apparent red light at 678nm but because of blueshift.
Well we are assuming the space cat (i.e. it is not an ordinary cat) is emitting a white light (it's a hot glowing cat!), that is, the peak is in the middle of the visible spectrum. The cat becomes closer to red as it moves away and to blue when it is moving towards us. If it goes fast enough, the peak shifts to IR (past the red) or UV (past blue/violet)
But yes, if it was a normal non-space cat, the peak would be in the IR normally (since cats are quite cool, in both senses of the word), and as it moves away the peak shifts to longer wavelengths, and as it moves towards us, it will go to shorter wavelengths, possibly becoming visible if fast enough.
This is true about cats' radiation but we usually mean reflectivity when describing a cat's color. This of course means there is a light source illuminating the cat and the wavelengths observed also depend on the properties of the light source.
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Depends on their response to wavelengths at rest, including IR (for blueshift) and UV (for redshift).
Redshift doesn't literally mean things appear red: the colors just remap, for example:
320 nm ๐ถ๏ธ โ 400 nm ๐ช
400 nm ๐ช โ 500 nm ๐ฉ
500 nm ๐ฉ โ 625 nm ๐ง
625 nm ๐ง โ 781 nm ๐ฟ (IR, CD laser wavenength)
For easy calculation, I chose an exactly 25% increase in wavelength, achievable if the cat is receding at 25 % of the speed of light.
Or vice versa for blueshift. For example, a low-pressure sodium lamp in old street lights is near-monochromatic at 589 nm (pale yellow), which will reach 678nm red at 15% redshift, while a CD infrared laser incoming at the same 0.15๐ speed will have the same apparent red light at 678nm but because of blueshift.
TL;DR
๐ณ๏ธโ๐ โ Blueshift
๐ณ๏ธโ๐ โ Redshift
Well we are assuming the space cat (i.e. it is not an ordinary cat) is emitting a white light (it's a hot glowing cat!), that is, the peak is in the middle of the visible spectrum. The cat becomes closer to red as it moves away and to blue when it is moving towards us. If it goes fast enough, the peak shifts to IR (past the red) or UV (past blue/violet)
But yes, if it was a normal non-space cat, the peak would be in the IR normally (since cats are quite cool, in both senses of the word), and as it moves away the peak shifts to longer wavelengths, and as it moves towards us, it will go to shorter wavelengths, possibly becoming visible if fast enough.
This is true about cats' radiation but we usually mean reflectivity when describing a cat's color. This of course means there is a light source illuminating the cat and the wavelengths observed also depend on the properties of the light source.
Wait, is the spacecat also a raycat? And also radioactive? This is going into the book of cryptids so make your answer weird
With respect, some space cats accelerate butthole first. You have neglected spacecat spin and axis of spacecat spin