Unfortunately there’s more bad news to report on the clear skies front. A new paper, available in pre-print on arXiv from researchers at NASA’s Ames Research Center, reports that 73.3% of images the agency’s new SPHEREx space telescope collected between May and September of last year were contaminated by at least one artificial satellite trail. And it’s only going to get worse from here.
We witnessed a surprise outburst late last week, from a lesser known periodic comet. Posts flashed across message boards late last week, alerting comet watchers to a dramatic change in brightness for periodic comet 220P McNaught. Though it wasn’t on our list for bright comets to watch for in 2026, Comet 220P is now in range of binoculars or a small telescope, low to the east at dawn as it heads towards perihelion this coming weekend.
If we’re to reach another star, chemical propulsion will not get us there in any reasonable time frame. We’re going to need a different propulsion technology, and one of the most promising seems to be a solar sail. These giant reflective surfaces form the basis of many interstellar missions. Combined with giant lasers pushing them, they can be accelerated to speeds unreachable by any other current technologies. However, according to a new paper available on arXiv from Chao Shen and Jiaze Li of the Harbin Institute of Technology, once those missions start reaching a significant percentage of the speed of light they’re going to run into a drag force from the light itself.
Inflation is awkward, possibly not even a proper theory, and it has reigned over cosmology for forty years anyway. Here is what it claims, the flatness, horizon, and monopole problems it solves, the structure-formation prediction it nailed, and the deep problems it still cannot escape.
Scientists at the SETI Institute searched for technological signals from 3I/ATLAS, the third interstellar object observed in our Solar System. Using the Allen Telescope Array (ATA) at the Hat Creek Radio Observatory in Northern California, the team scanned a wide range of radio frequencies for signs of extraterrestrial technology and found none, as expected based on other astronomical observations showing that the object exhibits natural comet-like composition and behavior. “Eventually, our own Voyager spacecraft will be extraterrestrial artifacts in other stellar systems,” said Dr. Sofia Sheikh, lead author on the paper. “Given that, it is important that we understand the natural distribution of interstellar objects so that we will be able to identify any anomalies that could one day be signs of an artificial interstellar object.” The team observed 3I/ATLAS for more than seven hours with the ATA, covering 1 to 9 gigahertz. This broad range allows scientists to search for narrowband radio signals, which are not produced by in nature and would be evidence of technology.
A look at why a cyclic, eternally repeating universe is such an appealing idea, and why the first serious attempt to build one, Richard Tolman's 1930s model of endless big bangs and big crunches, collapsed under the weight of entropy. The Big Bang keeps demanding a beginning.
The first mission devoted to observing the Martian atmosphere and its evolution, NASA’s MAVEN (Mars Atmosphere and Volatile Evolution), has ended after more than 11 years in orbit at Mars and a decade beyond its primary, one-year mission.
