Welcome to Photo of the Week. Today features a colorful lake made of toxic waste. Plus, get a glimpse of a newly discovered galaxy and a look at some exotic pets.

PHOTOGRAPH BY GHEORGHE POPA

The Roșia Poieni copper mine appears like a wound on Romania’s Apuseni Mountains. In 1987, President Nicolae Ceaușescu initiated the removal of residents from the neighboring village in order to create a place to discard the mine’s waste. What resulted was a viscous, artificial lake filled with water and sludge from the mine.

Pharmacist and nature photographer Gheorghe Popa grew up about two hours away by car and first encountered the dumping site in 2014. The unearthly scene mesmerized him: amid an otherwise picturesque mountain range, a lake tie-dyed in swirls of yellow, red, orange and turquoise. 

More images of unearthly beauty:
— See the Mississippi River's hidden history, uncovered by lasers 
— On the 'Island of the Colorblind,' paradise has a different hue 

PHOTOGRAPH BY WHALE RESEARCH SOLUTIONS

Chimpanzees use sticks to fish for termites and sea otters crack open clams with a rock. The whales in the photo above use bubbles to trap prey. What species of whale does this?

A. Beluga whale
B. Orca whale
C. Humpback whale
D. Sperm whale

PHOTOGRAPH BY ESA, EUCLID, EUCLID CONSORTIUM, NASA, IMAGE PROCESSING BY J.-C. CUILLANDRE, G. ANSELMI, T. LI 

3D MAP OF THE GALAXY: The team behind Euclid, a European Space Agency telescope, has an ambitious goal: to understand the hidden forces glueing the cosmos together and tearing the universe apart. After releasing their first treasure trove of data, Euclid has found a staggering 26 million galaxies, along with a host of hundreds of additional bizarre astronomic features.

BEFORE YOU GO: Holy cockatoo! See these photos of exotic pets and learn what happens when they outlive their owners...

Thanks for reading today’s newsletter, which was edited and curated by Jennifer Baik and produced by Amanda Williams-Bryant. Did someone forward this to you? Sign up here to catch next week’s Photo of the Week newsletter.