A "skull" on Mars and an illustration of an artificially stimulated retina NASA scientists have discovered a mysterious structure on Mars that may offer new insights into the Red Planet's watery past. The dark, pitted rock, nicknamed 'Skull Hill', was discovered by NASA's Perseverance rover as its searched for signs of ancient life in the hills and rocky outcrops of Mars' barren Jezero Crater — a bowl-shaped depression that scientists suspect once held a huge ancient lake . The rock stands out against the lighter-toned rock that surrounds it, leading scientists to suspect that it may not have formed there. Rather, it may have been transported on a Martian river or lake to its current position, billions of years ago. However, many questions still remain about the rock's origin and what it can tell us about the history of our cosmic neighbor. New color discovered In a study, scientists used a new way of displaying color imagery to push the boundaries of human vision. (Image credit: blackdovfx via Getty Images) A whole new dimension of vision could be just around the corner after scientists successfully hijacked the human eye to see a brand-new color called olo. The color, described by study participants as a "blue-green of unprecedented saturation," was made visible using a technique called "Oz" to stimulate a particular group of light receptors at the back of the participants' eyes. The researchers say their method could be developed to restore color vision in those with color blindness, and that it could potentially provide enhanced digital viewing experiences in the future. Discover more health news Sign up for the Live Science daily newsletter now Get the world’s most fascinating discoveries delivered straight to your inbox. Contact me with news and offers from other Future brands Receive email from us on behalf of our trusted partners or sponsors —Parasitic worm raises risk of cervical cancer, study finds —Simple blood test could reveal likelihood of deadly skin cancer returning, study suggests —How accurate are smart rings, and how do they compare to fitness watches? Life's little mysteries Pet cats, especially those with access to the great outdoors, sometimes bring their owners dead animals. (Image credit: zsv3207 via Getty Images) If you have an outdoor cat, you've probably been presented with "gifts" from your furry companion — usually in the form of dead birds and rodents. But have you ever wondered why they do this? Your cat had to use a lot of energy to capture this prize, so eating it themselves would be the most sensible action from a survival perspective. But experts say there are several hypotheses for why they continue this bizarre behavior. First quantum operating system The new operating system is the first in the world that allows quantum computers with different kinds of qubits to function together in a single network. (Image credit: Shutterstock) Scientists have made steps towards a quantum internet after developing the world's first operating system to facilitate connections between quantum computers. Operating systems, like Microsoft Windows and Apple iOS, manage and control our computers' hardware and software. They enable users to interact with applications and allow different devices to connect with each other. Most existing quantum computers are designed and built to carry out a specific function and use different kinds of quantum bits (qubits) to run their calculations. But now, a first-of-its-kind quantum operating system called QNodeOS has been developed to allow multiple quantum computers to connect and be controlled by a single central platform, regardless of the type of qubits they use. Discover more technology news —Schrödinger's cat-inspired quantum computing now 160 times more reliable thanks to new discovery —Dyson spheres could really exist — but there's a catch —'Beauty' particle discovered at world's largest atom smasher could unlock new physics Also in science news this week —Solar wind might be making water on the moon, groundbreaking NASA study reveals —Giant 'sea dragon' fossil could be largest mosasaur ever discovered in Mississippi —Parasitic worm raises risk of cervical cancer, study finds —Lion mauled gladiator to death 1,800 years ago in Roman Britain, controversial study suggests Science Spotlight Atlantic ocean currents regulate the climate, and they may be weakening, emerging research suggests. (Image credit: Nicholas Forder) The Atlantic Meridional Overturning Circulation, also known as the AMOC, is a large system of ocean currents that brings warm water from the tropics northwards and ferries colder water from north to south. The system, which acts like an enormous watery conveyor belt, ensures that the oceans are continually mixed and that heat is distributed around the planet. However, a mysterious "blob" of water in the North Atlantic that has puzzled scientists for decades could be an ominous signal that these essential currents are slowing down. So, what would this mean for us? Something for the weekend If you're looking for something a little longer to read over the weekend, here are some of the best long reads, book excerpts and interviews published this week. — Ancient DNA and modern genomes can reveal stories of past peoples, from the Iron Age to Chernobyl, geneticist says — What is the ancient Egyptian 'Eye of Horus' — and why is it found in so many burials? — A long-lost ice sheet could predict the future of New York City — one in which Lower Manhattan and Coney Island are 'perpetually submerged' Science in motion Scientists on an expedition to the South Sandwich Islands near Antarctica have revealed footage that is straight out of a horror movie: a deep-sea rattail fish swimming with two bloodsucking parasites latched onto either side of its head . The video, shared by the Schmidt Ocean Institute, shows the two parasitic crustaceans called copepods trailing alongside the rattail fish, their long egg sacs flowing behind them like a pair of pigtails. The footage was captured as part of an expedition to examine the seafloor and the diversity of weird and wonderful creatures that live down there. Follow Live Science on social media