Space News & Blog Articles

An expanding universe complicates this picture just a little bit, because the universe absolutely refuses to be straightforward. Objects are still emitting light, and that light takes time to travel from them over to here, but in that intervening time the universe grows larger, with the average distance between galaxies getting bigger (yes, I know that sometimes galaxies can collide, but we’re talking on average, at big scales here).

I honestly don’t have a decent analogy for you to explain how the universe is expanding without a center and without an edge. It just does, whether we can wrap our minds around it or not. But I CAN give you a way to think about it.

Satellite megaconstellations are quickly becoming the backbone of a number of industries. Cellular communication, GPS, weather monitoring and more are now, at least in part, reliant on the networks of thousands of satellites cruising by in low Earth orbit. But, as these constellations grow into the tens of thousands of individual members, the strain they are putting on the communications and controls systems of their ground stations is becoming untenable. A new paper from Yuhe Mao of the Nanjing University of Aeronautics and Astronautics and their co-authors hopes to alleviate some of that pressure by offloading much of the control scheme and network decision-making logic to satellites themselves.

Let’s start out with something that we can say for certain: we live in an expanding universe. Every single day, the universe gets a little bit bigger than it was the day before. But right away, when we say something like “we live in an expanding universe” certain questions start to pop up, and they’re far and away the most common kinds of questions that I get asked. If the universe is expanding, then what is it expanding into? And what is it expanding from? Where’s the edge of the universe, and where is it’s center?

Human beings are pretty familiar with the concept of "ice ages." Not only is their ample physical evidence to suggest that glacial periods occurred during the Pleistocene epoch - which lasted from ca. 2.58 million to 11,700 years ago, there are even Indigenous oral traditions that speak of lake formation and dramatic climate shifts in the distant past. Far from being mere myths, these traditions are considered preserved accounts that are corroborated by scientific findings. However, the cycles of glacial and interglacial periods that characterize the Pleistocene were merely the latest in a long line of historical shifts in Earth's climate.