Looking to buy a small or inexpensive TV and don't know where to start? These three TVs are each under $100 and among the most popular with Amazon users.

Using ideas borrowed from topological photonics, researchers in Singapore, France and the US have designed a compact antenna capable of handling information-rich terahertz (THz) signals. Reporting their results in Nature Photonics, the team, led by Ranjan Singh at the University of Notre Dame, say that with further refinements, the design could help underpin future sixth-generation (6G) wireless networks, allowing data to be shared at unprecedented speeds.

Archaeologists have uncovered evidence for repeated prehistoric occupation in the remote island cluster of Kitsissut, north of Greenland, indicating the first people in the High Arctic were skilled seafarers who had a profound impact on early Arctic environments.

Volcanic activity is not unique to Earth: traces of volcanic activity, such as lava tubes, have been found on Mars and the moon. Now, the University of Trento has demonstrated the existence of an empty lava tube even in the depths of Venus, a planet whose surface and geology have been largely shaped by volcanic processes.

Most shark fossils are just teeth—their cartilage skeletons usually decay long before they can fossilize. But in northwestern Arkansas, a series of geological sites known as the Fayetteville Shale has preserved dozens of rare, three-dimensional shark skeletons dating back more than 300 million years. In a new study published in Geobios, researchers reveal why: These fossils formed on a low-oxygen, highly acidic seafloor that preserved cartilage instead of destroying it.

Gas giants are large planets mostly composed of helium and/or hydrogen. Although these planets have dense cores, they don't have hard surfaces. Jupiter and Saturn are the gas giants in our solar system, but there are many other gas giant exoplanets in our galaxy and some are many times larger than Jupiter.

Using HARPS and HARPS-N spectrographs, astronomers have observed a nearby K-type star designated HD 176986, known to host two super-Earth exoplanets. The observations resulted in the discovery of another planet in the system at least several times more massive than Earth. The finding was detailed in a paper published January 28 in the Astronomy & Astrophysics journal.

Modern technologies increasingly rely on light sources that can be reconfigured on demand. Think of microlasers that can quickly switch between different operating states—much like a car shifting gears—so that an optical chip can route signals, perform computations, or adapt to changing conditions in real time. The microlaser switching is not a smooth, leisurely process, but can be sudden and fast. Generally, nearly identical "candidate" lasing states compete with each other in a microcavity, and the laser may abruptly jump from one state to another when external conditions are tuned.

Using an advanced machine-learning algorithm, researchers in the UK and Japan have identified several promising candidate locations for the long-lost landing site of the Soviet Luna 9 spacecraft. Publishing their results in npj Space Exploration, the team, led by Lewis Pinault at University College London, hope that their model's predictions could soon be tested using new observations from India's Chandrayaan-2 orbiter.

Pet owners want quick answers when their beloved cat or dog is sick. And if these furry friends are experiencing digestive distress, lethargy and fever, it's important to rapidly rule out serious illnesses like feline panleukopenia (also called feline parvovirus) and canine parvovirus. Now, researchers report improved lateral flow assays for at-home screening. In tests on veterinary clinic samples, the assays demonstrated 100% sensitivity and reproducibility for both parvoviruses.