Spock's home planet does not exist in our universe, but for Nimoy and many of his biggest fans, it is real. Perhaps only Leonard Nimoy knew how to sit shiva on Vulcan, but today that is what they are doing on that not-quite-real planet. I don't know how to speak Vulcan, but I suspect at a time like this the phrase they use there is "Alav Hashalom." Farewell, Leonard Nimoy. We will miss you here on Earth.