69-year-old Carol Ambruster was an assistant professor of astronomy and astrophysics at Villanova University.
Police were called to the 5500 block of Wayne Avenue around 9:00 p.m. Monday.
They found Ambruster's body inside her second floor apartment.
She had been stabbed multiple times in the chest and neck. Medics pronounced her dead at the scene.
Police say Ambruster's male roommate called them after finding her body.
Detectives questioned him. They say they have no suspects in the killing.
"The door to her apartment, which is a heavy wooden door, does not appear to have been forced open," Chief Inspector Scott Small told Action News.
The murder weapon was found inside the apartment.
Police said there appeared to be surveillance cameras in the building and were hoping video would help lead to a suspect.