Stephanie Olson is an astrobiologist and professor at Purdue University, US. From finding what chemical reactions are happening on far planets to guessing what conditions are needed for life to originate there, she does it all. But when she woke up one morning last week, Olson was alarmed to see that her dog Olive’s neck had turned green overnight.However, it did not take her long to remember that she is an early Earth geochemist and hence, she was equipped to uncover the mystery behind her pet’s green fur — green rust.
Once she figured out the reason, she took to Twitter to share this interesting incident. Moreover, she explained in a chain of tweets the reason behind this colouration. She also asked people for suggestions to get rid of the colour.
Olson explained: “The story begins with a lot of drool. Olive drools a lot. The pet is recently recovering from surgery, her drool needed to be isolated and hence, I attached a pet cone to the dog’s neck." According to Olson, dog drool contains iron porphyrin. When it comes into contact with oxygen, the iron reacts with oxygen forming very small particles of iron oxide, a process similar to rusting.
The dog was demoralised by the cone, so she slept on her stomach, which caused her drool-soaked neck to be isolated from the air in the room. Olive did not move while sleeping because she was sedated. This caused the bacteria in saliva to consume the little oxygen that she had in her neck fur. Lack of oxygen prevented rust in the dog’s neck fur, but it formed green rust, which is produced when rusting happens in low-oxygen environments.
I was alarmed to discover that my dog turned GREEN overnight. I had no idea why. But it turns out that, as an early Earth geochemist, I was perfectly prepared to find out! 🧵 pic.twitter.com/SnM3iwKXVM
— Dr. Stephanie Olson (@ExoStephO) July 18, 2021
After realising the reason, Olson looked at Olive’s neck and she found the red rust transitioning to green from her mouth to down her neck. She explained that the green rust was unusual because it was unstable in a normal environment. Olson ended her thread with a funny alternative theory — her dog was respecting her name Olive — a short form for Olivine, a green mineral.