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Neutral Hydrogen: The Next Big Game in Cosmology

The majority of the universe remains unmapped, but we have a potential window into it through a peculiar light emitted by nothing other than neutral hydrogen. Before stars and galaxies lit up the universe, the cosmos was a dark place filled mostly with neutral hydrogen. This was right after the Big Bang and the formation of the CMB—Cosmic Microwave Background. The CMB is like a baby picture of the universe when it was just 380,000 years old. But what came next was a long period called the “Dark Ages.” During this time, the universe didn’t have much going on in terms of visible light because there were no stars or galaxies yet. Frustratingly, most of the volume of the visible universe exists in these Dark Ages, which makes it a very valuable resource to learn about the nature of dark matter and dark energy. But…it was dark, so we can’t just make a bigger telescope and observe it. Thankfully, the neutral hydrogen that filled the universe during this epoch does emit a feeble kind of li...
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Antarctica’s Deception Island is the Perfect Place to Practice Exploring Mars

It’s not uncommon for space missions to be tested here on planet Earth. With the plethora of missions that have been sent to Mars it  is becoming increasingly likely that the red planet was once warmer, wetter and more habitable than it is today. To find evidence of this, a new paper proposes that Deception Island in Antarctica is one of the best places on Earth to simulate the Martian environment. The paper identifies 30 sites on the island that correspond well to places on Mars. The exploration of Mars has been a focus of space agencies worldwide, driven by the desire to understand the its geology, climate, possibility of past life, and excitingly the potential for future human colonisation. Early missions, such as NASA’s Mariner 4 in 1965, provided the first close-up images of Mars, while the Viking landers of the 1970s conducted the first successful surface experiments. In the 1990s and 2000s, orbiters like Mars Global Surveyor and rovers like Spirit and Opportunity helped us...
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Does Jupiter’s Moon Callisto Have an Ocean? The Evidence is Mounting

Some of our Solar System’s moons have become very enticing targets in the search for life. There’s growing evidence that some of them have oceans under layers of ice and that these oceans are warm and rich in prebiotic chemistry. NASA’s Europa Clipper is on its way to examine Jupiter’s moon Europa, and the ESA’s Jupiter Icy Moons Explorer is also on its way to the Jovian system to explore some of its icy moons. While the presence of an ocean on Europa is becoming widely accepted, there’s more uncertainty about the other Galilean moons. However, new evidence suggests that Callisto is very likely an ocean moon, too. Callisto is Jupiter’s second-largest moon, the third-largest moon in the Solar System, and the outermost Galilean moon . The Voyager probes gave us our first close looks at Callisto in 1979, and the Galileo spacecraft gave us our best images and science data during flybys between 1996 and 2001. Galileo provided the first evidence that Callisto may harbour a subsurface oc...
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DESI Found 300 Candidate Intermediate Mass Black Holes

If Intermediate-Mass Black Holes (IMBHs) are real, astronomers expect to find them in dwarf galaxies and globular clusters. There’s tantalizing evidence that they exist but no conclusive proof. So far, there are only candidates. The Dark Energy Spectroscopic Instrument (DESI) has found 300 additional candidate IMBHs. Logic says that IMBHs should exist. We know of stellar-mass black holes, and we know of supermassive black holes (SMBHs). Stellar-mass black holes have between five and tens of solar masses, and SMBHs have at least hundreds of thousands of solar masses. Their upper limit is not constrained. Astrophysicists think these black holes are linked in an evolutionary sequence, so it makes sense that there’s an intermediate step between the two. That’s what IMBHs are, and their masses should range from about 100 to 100 thousand solar masses. IMBHs could also be relics of the very first black holes to form in the Universe and the seeds for SMBHs. The problem is that there are n...
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Did Astronomers Just Witness the Formation of a “Strange Star”?

There are plenty of types of stars out there, but one stands out for being just a little weirder than the others. You might even say it’s strange. According to a paper from researchers at Guangxi University in China, the birth of one might have recently been observed for the very first time. A strange star is a (so far theoretical) compact star that is so dense it literally breaks down regular parts of atoms (like neutrons) into their constituent quarks. Moreover, even those quarks (the up and down that comprise a neutron) get compressed into an even rarer type of quark called a strange quark – hence the name strange star. Technically, the “strange” matter that a strange star would be composed of is a combination of up, down, and strange quarks. But, at least in theory, this mix of sub-hadronic particles could even be more stable than a traditional neutron star, which is similar to a strange star but doesn’t have enough gravity to break down the neutrons. Fraser discusses strange...
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NASA’s SPHEREx Launches Soon and Will Search For Water in Molecular Clouds

As far as we can tell, life needs water. Cells can’t perform their functions without it. Some have suggested that other exotic liquids, like liquid methane, could do the job on worlds like Saturn’s moon Titan. That idea is highly speculative, though. So, it makes sense that NASA is launching a spacecraft dedicated to the search for water. SPHEREx stands for Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer . It’s scheduled to launch on February 27th. It has a single instrument and one observing mode. Part of its mission is to map the sky in near-infrared and measure the spectra of 450 million galaxies. The results will help scientists understand the expansion of the Universe and the origin and evolution of galaxies. This image shows a semi-frontal view of the SPHEREx observatory during integration and testing at BAE Systems (Boulder, CO). Image Credit: NASA/JPL-Caltech. Its other scientific goal is to probe molecular clouds for water ic...
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What Would Actual Scientific Study of UAPs Look Like?

For those who missed the memo, UFOs (Unidentified Flying Objects) are now called UAPs (Unidentified Aerospace-Undersea Phenomena). The term UFO became so closely tied to alien spacecraft and fantastical abduction stories that people dismissed the idea, making any serious discussion difficult. The term UAP is a broader term that encompasses more unexplained objects or events without the alien spaceship idea truncating any useful or honest discussion. While the name change is helpful, it’s just the beginning. We need a way to study UAPs scientifically, and new research shows us how. Though the idea of alien spacecraft visiting us isn’t always taken very seriously, the effort to document UAP and understand them goes back decades. In current times, governments around the world have made more serious efforts to understand what’s behind the phenomena. Most notably, NASA recently initiated a study into UAP called the Unidentified Anomalous Phenomena Independent Study and released its fina...
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