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Showing posts from November, 2024

Interstellar Objects Can't Hide From Vera Rubin

We have studied the skies for centuries, but we have only found two objects known to come from another star system. The first interstellar object to be confirmed was 1I/2017 U1, more commonly known as ?Oumuamua. It was discovered with the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) and stood out because of its large proper motion. Because ?Oumuamua swept through the inner solar system, it was relatively easy to distinguish. The second interstellar object, 2I/Borisov, stood out because it entered the inner solar system from well above the orbital plane. But while we have only discovered two alien visitors so far, astronomers think interstellar objects are common. It’s estimated that several of them visit our solar system each year, and there may be thousands within the orbit of Neptune on any given day. They just don’t stand out, so we don’t notice them. But that could soon change. The Vera C. Rubin Observatory is scheduled to come online in 2025. Unlike many lar...

The Early Earth Wasn’t Completely Terrible

Earth formed 4.54 billion years ago. The first period of the history of the Earth was known as the Hadean Period which lasted from 4.54 billion to 4 billion years ago. During that time, Earth was thought to be a magma filled, volcanic hellscape. It all sounds rather inhospitable at this stage but even then, liquid oceans of water are thought to have existed under an atmosphere of carbon dioxide and nitrogen. Recent research has shown that this environment may well have been rather more habitable than once thought.  The name ‘Hadean’ comes from Hades, the Greek god of the underworld. It nicely reflects the hot, hostile climate of the early Earth. During this period, Earth was largely a molten, chaotic world with volcanic eruptions a common sight on the landscape. Overhead, there would be regular visitors from space with meteorites and comets impacting the surface as the crust is still forming. Despite these conditions, it seems that water also began to accumulate as the planet co...

Globular Clusters Evolve in Interesting Ways Over Time

Globular clusters are among the oldest objects in the Universe. The early Universe was filled with dwarf galaxies and its just possible that globular clusters are the remains of these ancient relics. Analysis of the stars in the clusters reveals ages in the region of 12-13 billion years old. A new paper just published shows that the globular clusters are home to two distinct types of stars; the primordial ones with normal chemical composition and those with unusual heavy amounts of heavier elements.  Globular clusters are dense, spherical collections of stars that orbit the outer regions of galaxies, usually in the galactic halo. They contain hundreds of thousands, sometimes millions of stars bound together by gravity. They differ from open clusters, which are younger and less tightly bound and found in the main body of a galaxy. Globular clusters in contrast, are ancient with ages typically in the regions of 10 to 13 billion years old.  M13 – Credit: R. Jay GaBany There...

A Superfast Supercomputer Creates the Biggest Simulation of the Universe Yet

Scientists at the Department of Energy’s Argonne National Laboratory have created the largest astrophysical simulation of the Universe ever. They used what was until recently the world’s most powerful supercomputer to simulate the Universe at an unprecedented scale. The simulation’s size corresponds to the largest surveys conducted by powerful telescopes and observatories. The Frontier Supercomputer is located at the Oak Ridge National Laboratory in Tennessee. It’s the second-fasted supercomputer in the world, behind only El Capitan , which pulled ahead in November , 2024. Frontier is the world’s first exascale supercomputer, though El Capitan has joined the ranks of exascale supercomputing. The new Frontier simulation is record-breaking and is now the largest simulation of the Universe ever conducted. Its exascale computing allows it to simulate a level of detail that was unreachable prior to its implementation. Exascale is so advanced that it’s difficult to fully exploit its capa...

How Much Are Asteroids Really Worth?

Popular media love talking about asteroid mining using big numbers. Many articles talk about a mission to Psyche, the largest metallic asteroid in the asteroid belt, as visiting a body worth $10000000000000000000, assumedly because their authors like hitting the “0” key on their keyboards a lot. But how realistic is that valuation? And what does it actually mean? A paper funded by Astroforge, an asteroid mining start-up based in Huntington Beach, and written by a professor at the Colorado School of Mine’s Space Resources Program takes a good hard look at what metals are available on asteroids and whether they’d genuinely be worth as much as the simple calculations say that would be. The paper divides metals on asteroids into two distinct types—those that would be worth returning to Earth and those that wouldn’t. Really, the only metals judged to be worthy of returning to Earth are the platinum-group metals (PGMs), which are known for their extraordinarily high cost, relatively low su...

Is There Seismic Activity on Venus? Here’s How We Could Find Out

Venus is often referred to as Earths twin but size and mass are the only similarities. A visitor to one of our nearest neighbours would experience a very different world at the surface. Unlike other planets in the Solar System, Venus seems to show very little active volcanism. The environmental conditions on the surface are harsh so a researcher has suggested a combination of an orbiter, a balloon and a lander would be able to work together to detect seismic activity under the surface. Venus is the second planet from the Sun and is enshrouded in a thick atmosphere. From Earth, it is impossible to see any visual detail on the surface of the planet due to the planet-wide thick clouds that engulf it. The atmosphere is composed mostly of carbon dioxide with clouds of sulfuric acid which together have raised the surface temperature to a staggering ~475°C. Venus is a pretty inhospitable world given these high surface temperatures, atmospheric pressure equivalent to being a kilometre under ...

An AI Chemist Made A Catalyst to Make Oxygen On Mars Using Local Materials

Breaking oxygen out of a water molecule is a relatively simple process, at least chemically. Even so, it does require components, one of the most important of which is a catalyst. Catalysts enable reactions and are linearly scalable, so if you want more reactions quickly, you need a bigger catalyst. In space exploration, bigger means heavier, which translates into more expensive. So, when humanity is looking for a catalyst to split water into oxygen and hydrogen on Mars, creating one from local Martian materials would be worthwhile. That is precisely what a team from Hefei, China, did by using what they called an “AI Chemist.” Unfortunately, the name “AIChemist” didn’t stick, though that joke might vary depending on the font you read it in. Whatever its name, the team’s work was some serious science. It specifically applied machine learning algorithms that have become all the rage lately to selecting an effective catalyst for an “oxygen evolution reaction” by utilizing materials nati...

Asteroid Samples Returned to Earth Were Immediately Colonized by Bacteria

We’ve known for a while that complex chemistry occurs in space. Organic molecules have been detected in cold molecular clouds , and we have even found sugars and amino acids, the so-called “building blocks of life,” within several asteroids . The raw ingredients of terrestrial life are common in the Universe, and meteorites and comets may have even seeded Earth with those ingredients. This idea isn’t controversial. But there is a more radical idea that Earth was seeded not just with the building blocks of life but life itself. It’s known as panspermia, and a recent study has brought the idea back to popular science headlines. But the study is more subtle and interesting than some headlines suggest. Panspermia became popular in the 1800s and 1900s when it became clear that life arose surprisingly early on Earth. On a geologic scale, cellular life appears almost as soon as Earth cooled enough to support it. Given the complexity of DNA and living cells, how could such a thing have evolv...

An Insanely High-Resolution Image of the Sun

Our local star the Sun has been the source of many studies from ground based telescopes to space based observatories. The ESA Solar Orbiter has been approaching the Sun, capturing images along the way in unprecedented detail. It arrived at its halfway point in March last year and captured a series of 25 images. They have now been stitched together to reveal an astonishingly high resolution image. You can even zoom in to see individual granules in the solar photosphere.  In comparison to Earth, the Sun is massive but in when it comes to other stars, it’s pretty average. It provides energy to sustain life through the process of nuclear fusion deep in its core.  The hydrogen atoms are fused into helium generating so much energy that heat and light bathes our planet. Like all other stars, the Sun is a great big ball of electrically charged gas with a visible surface temperature of about 5,500°C. It measures a staggering 1.39 million km across and lies at an average distance of ...

The Hubble and FU Orionis: a New Look at an Old Mystery

In 1936 astronomers watched as FU Orionis, a dim star in the Orion constellation, brightened dramatically. The star’s brightness increased by a factor of 100 in a matter of months. When it peaked, it was 100 times more luminous than our Sun. Astronomers had never observed a young star brightening like this. Since then, we’ve learned that FU Orionis is a binary star. It’s surrounded by a circumstellar disk and the brightness episodes are triggered when the star accretes mass from the disk. There are other young stars similar to FU Orionis, and it’s now the namesake for an entire class of variable young stars that brighten in the same manner. FU Ori stars are a sub-class of T-Tauri stars , young, pre-main sequence stars that are still growing. Astronomers have modelled FU Ori’s accretion and brightness episodes with some success. But the nature of the disk-star interface has remained a mystery. Attempts to image the boundary between the two haven’t been successful. Until now. Astron...

China Tests a Reusable Inflatable Module in Space

Inflatable space modules are not a new concept, NASA have been exploring the possibility since the 1960’s. The Chinese Space Agency is now getting in on the act and is testing its new inflatable module which is part of its Shijian-19 satellite launch. To get it into orbit the capsule was compressed and folded and then inflated once in orbit. Following completion of the tests, it re-entered the atmosphere, landing in the Gobi Desert on 10th October. The goal is for this to be used to extend its space station in the same way NASA have been exploring expansion of ISS.  The idea of inflatable space capsules offers a lightweight solution which simplifies the launch process. Their development began back in the 1960’s but real progress was seen with projects like TransHub that looked at new advanced materials. Even though TransHub was cancelled it was a precursor to ventures like the Bigelow Aerospace module known as BEAM. It was tested in 2016 on the ISS and proved the concept could wo...

Fantastic New Image of the Sombrero Galaxy From Webb

NGC 4594 is an unusual galaxy. It was discovered in 1781 by Pierre Méchain, and is striking because of a symmetrical ring of dust that encircles the visible halo of the galaxy. Images taken of the galaxy in 2003 show this dusty ring in detail, where it almost resembles the brim of a large hat. So it’s understandable that NGC 4594 is more commonly known as the Sombrero Galaxy. Now the James Webb Space Telescope has captured an amazingly sharp image of the galaxy, and it’s revealing some interesting surprises. The famous Sombrero galaxy. The prominent dust lane and halo of stars and globular clusters give this galaxy its name. Credit: NASA/ESA and The Hubble Heritage Team (STScI/AURA) Although Hubble’s view of the Sombrero Galaxy is stunning, it is bound by the limits of the optical spectrum. In the Hubble image, the thick dust ring obscures any stars that may be forming within it, and the brilliance of the active black hole at the heart of the galaxy outshines any details at the ce...

We’re Living in an Abnormal Galaxy

Astronomers often use the Milky Way as a standard for studying how galaxies form and evolve. Since we’re inside it, astronomers can study it in detail with advanced telescopes. By examining it in different wavelengths, astronomers and astrophysicists can understand its stellar population, its gas dynamics, and its other characteristics in far more detail than distant galaxies. However, new research that examines 101 of the Milky Way’s kin shows how it differs from them. One powerful way to understand things is to compare and contrast them with others in their class, a technique we learn in school. Surveys are an effective tool to compare and contrast things, and astronomical surveys have contributed an enormous amount of foundational data towards the effort. The Sloan Digital Sky Survey (SDSS), the Two Micron All Sky Survey (2MASS), and the ESA’s Gaia mission are all prominent examples. The Satellites Around Galactic Analogs (SAGA) Survey is another, and its third data release ...

NASA Releases its Moon Phases Animation for 2025

Every year, NASA releases a detailed simulation of the Moon that shows how it will change through the year. They produce a couple of versions that show how it appears from the northern and southern hemisphere and others that highlight different features. Not only does it show the phases through the year but it also shows the change in size as its completes its orbit. The change in apparent size of the Moon is a result of its elliptical orbit so that it can appear up to 30% brighter.  The Moon is Earth’s only permanent natural satellite. It has captivated humans for thousands of as it orbits at an average distance of 384,400 kilometres. It plays a key role in shaping our tides through its gravitational pull. The lunar surface is a desolate, rocky world with colossal mountains, and plains known as maria.  It has no atmosphere and so experiences extreme temperature shifts, from intense solar heating in the day to freezing cold at night. Over the centuries, it has inspired count...