If There Were a War in Space, Debris Would Destroy all Remaining Satellites in About 40 Years

The destruction of a single satellite could be catastrophic for our orbital endeavours. Image Credit: ESA

On one particular day in 2021, astronauts and cosmonauts aboard the ISS must have felt a pin-prick of fear and uncertainty. On November 15th of that year, Russia fired an anti-satellite missile at one of its own defunct military satellites, Tselina-D. The target weighed about 1,750 kg, and when the missile struck its target, the satellite exploded into a cloud of hazardous debris.

NASA woke the crew on the International Space Station in the middle of the night and told them to take precautions and prepare for a possible impact. The Chinese space station Tiangong was also in danger, and multiple countries and space agencies condemned Russia’s foolhardy behaviour.

But there was no way to contain the debris.

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Light Pollution is Out of Control

The Earth at night. What will it look like 100 years from now? Image credit: NASA-NOAA

Concern over global light pollution is growing. Astronomers are noticing its growing effect on astronomical observations, just as predicted in prior decades. Our artificial light, much of which is not strictly necessary, is interfering with our science.

But there’s more than just scientific progress at stake. Can humanity afford to block out the opportunities for wonder, awe, and contemplation that the night sky provides?

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A New Way to Measure Distances in the Universe

Image of the large-scale structure of the Universe, showing filaments and voids within the cosmic structure. Credit: Millennium Simulation Project. Now, the latest FLAMINGO simulation provide more detail about the evolution of the Universe within these structures.
Image of the large-scale structure of the Universe, showing filaments and voids within the cosmic structure. Who knows how many other civilizations might be out there? Credit: Millennium Simulation Project

If we want to understand the Universe, we have to start with its size. Ancient people had no idea there was a Universe the way we understand it now, and no idea of its size. They thought there was the Earth, with everything else rotating around it. It was the only conclusion within reach for a long time.

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Geoengineering is Shockingly Inexpensive

Geoengineering isn't a quick fix for our climate crisis, and it's also expensive. Image Credit: University of Leeds

Despite decades of warnings and international climate agreements, global carbon emissions are still rising. Carbon emissions seem like an unstoppable juggernaut as energy-hungry humans keep breeding and pursuing more affluent lifestyles. Reducing emissions won’t be enough to confront the climate crisis; we need additional solutions.

Geoengineering, also called climate engineering, could be the solution we seek. But is it financially feasible?

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These New Computer Simulations of the Sun are Hypnotic

Computer simulation of magnetic structures in solar-like conditions. Image: Jörn Warnecke

It’s almost impossible to over-emphasize the primal, raging, natural power of a star. Our Sun may appear benign in simple observations, but with the advanced scientific instruments at our disposal in modern times, we know differently. In observations outside the narrow band of light our eyes can see, the Sun appears as an enraged, infuriated sphere, occasionally hurling huge jets of plasma into space, some of which slam into Earth.

Jets of plasma slamming into Earth isn’t something to be celebrated (unless you’re in a weird cult); it can cause all kinds of problems.

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A Few Interstellar Objects Have Probably Been Captured

Artist’s impression of the first interstellar asteroid/comet, "Oumuamua". This unique object was discovered on 19 October 2017 by the Pan-STARRS 1 telescope in Hawaii. Credit: ESO/M. Kornmesser

When Oumuamua travelled through our Solar System back in 2017, people around the world paid attention. It was the first Interstellar Object (ISO) astronomers had ever identified. Then in August 2019, Comet 2I Borisov travelled through our Solar System, becoming the second ISO to cruise through for a visit. Together, the visiting ISOs generated a wave of inquiry and speculation.

There’s bound to be more ISOs than just those two, and a new study says our Solar System has probably captured some of these interstellar visitors, though they don’t stay for long.

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Each Planetary Nebula is Unique. Why Do They Look So Different?

A large collage of planetary nebulas processed by Judy Schmidt. All are presented north up and at apparent size relative to one another. Colors are aesthetic choices, especially since most planetary nebulas are imaged with narrowband filters. Image Credits: NASA / ESA / Judy Schmidt

When it comes to cosmic eye candy, planetary nebulae are at the top of the candy bowl. Like fingerprints—or maybe fireworks displays—each one is different. What factors are at work to make them so unique from one another?

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Remnants of a Relict Glacier Found Near the Equator on Mars

This image shows what scientists believe is a relict glacier near Mars’ Equator. Image Credits: NASA MRO HiRISE and CRISM false color composite. Lee et al. 2023

New results presented at the 54th Lunar and Planetary Science Conference could change our approach to Mars exploration. Scientists studying the surface of Mars discovered a relict glacier near the planet’s equator. The relict glacier could signal the presence of buried water ice at the planet’s mid-latitudes.

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The Universe Sparkles in Gamma Rays in this New NASA Animation

Cosmic fireworks, invisible to our eyes, fill the night sky. We can get a glimpse of this elusive light show thanks to the Large Area Telescope (LAT) aboard NASA’s Fermi Gamma-ray Space Telescope, which observes the sky in gamma rays, the highest-energy form of light. Image Credit: NASA’s Marshall Space Flight Center/Daniel Kocevski

We’ve come a long way since gamma rays were discovered.

The late 1800s and early 1900s were a time of great scientific advancements. Scientists were just getting a handle on the different types of radiation. Radium featured prominently in the experiments, including one by French scientist Paul Ulrich Villard in 1900.

Radium decays readily, and scientists had already identified alpha and beta radiation coming from radium samples. But Villard was able to identify a third type of penetrating radiation so powerful even a layer of lead couldn’t stop it: gamma rays.

Now we have a gamma ray detector in space, and it’s showing us how the Universe sparkles with this powerful energy.

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Ultra-Massive Black Holes: How Does the Universe Produce Objects So Massive?

Illustration of the supermassive black hole at the center of the Milky Way. Credit: NRAO/AUI/NSF
Illustration of the supermassive black hole at the center of the Milky Way. It's huge, with over 4 times the mass of the Sun. But ultramassive black holes are even more massive and can contain billions of solar masses. Image Credit: Credit: NRAO/AUI/NSF

Black holes are the most massive objects that we know of in the Universe. Not stellar mass black holes, not supermassive black holes (SMBHs,) but ultra-massive black holes (UMBHs.) UMBHs sit in the center of galaxies like SMBHs, but they have more than five billion solar masses, an astonishingly large amount of mass. The largest black hole we know of is Phoenix A, a UMBH with up to 100 billion solar masses.

How can something grow so massive?

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