It clearly says it's an Atmel AVR programmer - why would you imagine it supports anything else?.https://www.electronicscomp.com/usb...Ozm7VpgBTVrGzZDvJnNpSwlHVE3zh8IQaAhpOEALw_wcB
I do not understand whether programmer given in link supports the AT89C51 device or not
But this datasheet for the AT89C51 from Atmel doesn't say anything about it being part of the AVR family.It clearly says it's an Atmel AVR programmer - why would you imagine it supports anything else?.
A word of caution with those programmers in general, if you ever get involved with older ICs / MCUs:So far I haven't found an 8 bit chip it doesn't program..
Your wife probably moved it!I had one of those back in the 90s and a UV eraser - used it mainly for UVEPROMS (UVPROMS?) and GALs. No idea where it went.