Why won't the following code work? Mouse.hit

This code is in a Local Script in a tool. It should create parts at the location of the mouse with the Object Hearts as a child of it. It creates the part with the child, but it spawns at 0,0,0. Any ideas?

local tool = script.Parent
local player = game.Players.LocalPlayer
local mouse = player:GetMouse()

local function onActivate()
    local character = tool.Parent
    local hit = mouse.Hit.p
    local part = Instance.new("Part", character)
    local hearts = tool.Hearts:Clone()
    part.Anchored = true
    part.Size = Vector3.new(1, 1, 1)
    part.CanCollide = false
    part.Position = Vector3.new(hit)
    hearts.Parent = part
end

tool.Activated:connect(onActivate)