Here is the full list of all 15 Desert Bus VR achievements.
Drive ten miles
Play for 5 days
Kill a poor, innocent bug
Get towed all the way to the start
Drive one mile
Start the bus
Join a multiplayer game
Make it to Las Vegas
Make it back to Tuscon
Play for 10 days
Spend more time on the road than it took to program the game
Drive the equivalent length of Route 66 (2448mi)
Drive the distance from New York City to Los Angeles (2777mi)
Drive the equivalent length of Earth's circumference (24,901mi)
Ride along for a complete trip