Hanka, designated PX8-987 by the Tau'ri, was a planet in the Milky Way galaxy, which held a Stargate. The entire population was wiped out by the Goa'uld Nirrti when she released a Engineered Virus into the planet's water and ground.
As a result, everyone died, including Stargate Command team SG-7, leaving a young twelve year old girl named Cassandra as the only survivor. SG-1 brought her back through the Stargate and Cassandra nicknamed "Cassie" now lives on Earth.
A large sign is on display near the Stargate which announces "Welcome to Hanka" and bears the symbol of SG-7. It identifies the presence of the "Douglas Mclean Memorial Observatory" and names SG-7's late commander as "John Smith".