Space

The last of its kind? Space

The last of its kind?

Stellar streams consist of groups of stars moving in orbit together. They are usually remnants of small galaxies that were absorbed by larger galaxies or former star clusters. The Phoenix stream discovered four years ago is the latter. It was, as researchers show in an article in Nature, once a globular cluster, and a very special one at that. Globular clusters are special objects in themselves. Imagine the night sky full of gleaming stars shining much brighter than the brightest planets in our Solar System. The average distance between two stars of a globular cluster is only 0.1 light-years,…
How many planets fit into a star’s habitable zone? Life

How many planets fit into a star’s habitable zone?

The habitable zone of our Solar System is relatively narrow. Mars is at the very outer edge of it, while Venus, which orbits closer to the Sun than Earth, is not quite inside it. Of eight planets, only the Earth is at just the right distance from its host star. A ratio like this would naturally lower the chances of finding inhabitable worlds in the universe. But is the Solar System an exception or the rule? Astronomers have, in fact, found other star systems that give a rosier outlook. For instance, three planets are in the habitable zone of…
This star system will never be the Solar System Astrophysics

This star system will never be the Solar System

TYC 8998-760-1 might someday become something like our Sun. Right now, however, the young star is still a few billion years away from that. It’s been around for only about 17 million years. If it were the Sun, there would still be a long time before it would even be able to watch the dinosaurs. Nevertheless, the whippersnapper is still something special: astronomers using the European Southern Observatory’s (ESO) Very Large Telescope (VLT) photographed it and found two planets in its orbit. “Even though astronomers have indirectly detected thousands of planets in our galaxy, only a tiny fraction of…
Centaurs: they’ve been with us for a long time Space

Centaurs: they’ve been with us for a long time

We’ve been waiting for extraterrestrial visitors our whole lives – but in reality, they’re already here and have been with us for a long time. No, I don’t mean “Men in Black.” But it’s also not science fiction, it’s the truth. When astronomers discovered 2017 1I/ʻOumuamua, their surprise was enormous: we’d never seen an interstellar object inside our Solar System before. Or had we? We had. For some time, astronomers have known about asteroids that don’t orbit the Sun in the same plane as the planets (the ecliptic), but instead on orbits that are at a greater or smaller…
Meanwhile, in the outer edges of the Solar System Space

Meanwhile, in the outer edges of the Solar System

Gonggong, Quaoar, Orcus, Salacia, Gǃkúnǁ’hòmdímà, Leleākūhonua. You’ve probably never heard of the names of any of these worlds before (except for maybe Quaoar), but they are all very real celestial bodies that likely meet the definition of a dwarf planet and thus would have had the same claim to the title of “planet” as Pluto, right up until the time Pluto was demoted from planet status. The reason you won’t find them on any night-sky charts for amateur astronomers is because their orbits are so far away from the Sun that it was basically a miracle that any of…
In the orbit of two giants Astrophysics

In the orbit of two giants

Eta Carinae, approximately 7500 light-years from Earth, has everything that an astronomer could want. First, there’s the nebula surrounding Eta Carinae. The so-called Homunculus Nebula is still growing. It has the shape of two opposing cones, whose tips originate in Eta Carinae, and measures more than 0.5 light-years from end to end. From the propagation rate of up to 700 km/s, the existence of the nebula can be traced back to an outburst in the 1840s. Second, it is not just a single star, but a binary system consisting of two blue giants. The primary star has a mass…
When you gotta go, you gotta go, even on the Moon… Fun

When you gotta go, you gotta go, even on the Moon…

Space is harsh and uncomfortable. That’s true for all human bodily functions. But maybe you’ve spent some time thinking about this problem and you have an idea for the perfect space toilet? It could win you $20,000 if it meets the following specifications: General requirements Easy to use Odor control Usable for at least 14 days Usable for urine, feces, vomit, diarrhea, menses Usable by female and male users between 58 to 77 inches tall and 107 to 290 lbs Also usable by sick crew members, e.g., able to capture vomit without requiring the crew member to put his/her…
Moving blocks of ice around on Triton – the reality Other books

Moving blocks of ice around on Triton – the reality

May 24, 2082, Neptune’s moon Triton: The hero of one of my novels, Nick, tries to move a block of ice weighing 80 kg (176 lbs). But it’s damn hard, even with Triton’s low force of gravity. “On Earth, the ice would slide because its bottom would melt due to the pressure, like under the blade of a skate, but it’s too cold for that here,” Nick thinks. A mistake, a Swedish reader just wrote to me. The idea that ice skating works because ice melts under pressure and then forms a lubricating layer is old. Ice does in…