Comets inhabit the cold reaches of the Solar System: the Kuiper Belt and the Oort Cloud. Occasionally, one passes through the inner Solar System, but mostly they keep to themselves out there. These dirty snowballs are agglomerations of rock and dust, and frozen volatiles like water, carbon dioxide, methane, and ammonia. They also contain organic materials.
Space News & Blog Articles
Scientists have known that Mars has water for some years, documenting ice beneath the surface, moisture locked in soil, and vapour drifting through the thin atmosphere. The challenge facing future human missions isn't finding water on the Red Planet, it’s figuring out how to actually extract and use it.
Stars change in brightness for all kinds of reasons, but all of them are interesting to astronomers at some level. So imagine their excitement when a star known as J0705+0612 (or, perhaps more politically incorrectly, ASASSN-24fw) dropped to around 2.5% of its original brightness for 8.5 months. Two new papers - one from Nadia Zakamska and her team at the Gemini Telescope South and one from Raquel Forés-Toribio at Ohio State and her co-authors - examine this star and have come to the same conclusion - it’s likely being caused by a circumsecondary disk.
Space debris encompasses thousands of defunct satellites, spent rocket stages, and fragments from collisions or explosions that orbit Earth at speeds exceeding 27,000 kilometres per hour. This growing population of human made junk poses collision risks to operational spacecraft and, when gravity eventually pulls larger pieces down through the atmosphere, can threaten people on the ground with falling fragments that sometimes survive reentry intact.
Bacteria and the viruses that infect them have been locked in an evolutionary battle for billions of years. Bacteria evolve defences against viral infection and viruses develop new ways to breach those defences. This process shapes microbial ecosystems across Earth, from ocean depths to soil communities. But what happens when you take that battle to space?
Supermassive Black Holes (SMBHs), which reside at the center of many galaxies, play a central role in the evolution of these cosmic structures. This includes how they power Active Galactic Nuclei (AGNs), in which the core region emits enough radiation and light to temporarily outshine all the stars in the disk. They also "seesaw" between relativistic jets emanating from their poles to outflows of jets that suppress star formation in the surrounding core. Despite this broad understanding, scientists have been waiting for the day when they can peer directly into the heart of a galaxy's core and see what's going on there.
We live near a fusion reactor in space that provides all our heat and light. That reactor is also responsible for the creation of various elements heavier than hydrogen, and that's true of all stars. So, how do we know that stars are element generators? Many clues lie hidden in stellar spectra, since they contain fingerprints of various elements cooked up by the stars.
Some galaxies in the early universe were absolute powerhouses, churning out stars at rates that would dwarf the Milky Way's modest stellar production. These "monster galaxies," buried deep in dust between 10 and 12 billion years ago, are thought to be the ancestors of today's giant elliptical galaxies. But what drove them to grow so violently has remained frustratingly unclear.
A team of predominantly Canadian researchers are using massive galaxy clusters and the JWST to study low-mass galaxies from 13.5 billion years ago all the way up to 5 billion years ago. The clusters are used as gravitational lenses to expand the JWST's reach. It's called CANUCS, the Canadian NIRISS Unbiased Cluster Survey.
Back in 2005 (over 20 years ago!), Fraser wrote an article about the dangers of electrostatic discharge to astronauts on the Moon and Mars. Anyone that lives in the cold regions of our own planet, with its exceedingly dry interiors for half the year, knows the unpleasantness that goes along with getting shocked when you touch a metal surface. In space, that problem gets much worse, and could potentially prove fatal to astronauts or electromechanical systems if not dealt with properly. A new paper from Bill Farrell of the Space Science Institute and Mike Zimmerman of Johns Hopkins University, which was published in Advances in Space Research, goes over how that specific problem of “tribocharging” affects the operation of lunar rovers.
We all know people that seem to defy aging and appear much younger than they actually are. This same phenomenon happens in astronomy, too. Some stars just don't seem to age the same way other stars do.
We know what will happen to the Sun and our Solar System because we can look outward into the galaxy and examine older Sun-like stars in their evolutionary end states. Nothing lasts forever, including a star's hydrogen. Eventually, stars deplete their hydrogen fuel and leave the main sequence behind. Stars with masses similar to the Sun will first swell and turn red, then shed their outer layers. That's what we see when we gaze at older Sun-like stars.
If humans are ever going to expand into space itself, it will have to be for a reason. Optimists think that reason is simply due to our love of exploration itself. But in history, it is more often a profit motive that has led humans to seek out new lands. So, it stands to reason that, in order for us to truly begin space colonization, we will have to have a business-related reason to do so. A new paper from the lab of Srivatsan Raman at the University of Wisconsin-Madison and recently published in PLOS Biology, describes one potential such business case - genetically modifying bacteriophages to attack antibiotic resistant bacteria.
For a long time, scientists assumed that Earth's water was delivered by asteroids and comets billions of years ago. This coincided with the Late Heavy Bombardment (ca. 4.1 to 3.8 billion years ago), a period when planets and bodies in the Solar System experienced a much higher rate of impacts. According to this theory, the planets of the inner Solar System were unable to retain volatile elements such as water due to their proximity to the Sun. However, recent findings from the analysis of lunar rocks and regolith returned by the Apollo missions have cast doubt on this assumption.
The Hubble Mission Team has been feeding us a steady stream of images from the space telescope that are focused on star formation. The latest image is of Lupus 3, a star-forming region about 500 light-years away. Lupus 3 features bright young stars that have emerged from their gaseous cocoons, and those that are still growing inside of theirs.
We now have direct images of two supermassive black holes: M87* and Sag A*. The fact that we can capture such images is remarkable, but they might be the only black holes we can observe. That is, unless we take radio astronomy to a whole new level.
ALMA is the most powerful radiotelescope in the world, and among its many scientific endeavours is the study of protoplanetary disks around young stars. The process of planet formation is a major theme in astronomy, and with its ability to reposition its 66 radio antennae, ALMA can zoom in on dusty protoplanetary disks and spy the early indications of exoplanet formation.
Material science plays an absolutely critical role in space exploration. So when a new type of self-healing composite is announced, it’s worth a look–especially when the press release specifically calls out its ability to repair microtears associated with micrometeoroid impacts on satellites. It sounds like just such a composite material was recently invented at North Carolina State University - and it’s even already been spun out into a start-up company.
How can scientists estimate the pH level of Enceladus’ subsurface ocean without landing on its surface? This is what a recently submitted study hopes to address as a team of scientists from Japan investigated new methods for sampling the plumes of Enceladus and provide more accurate measurements of its pH levels. This study has the potential to help scientists better understand the subsurface ocean conditions on Enceladus and whether it’s suitable for life as we know it.
Baby pictures are some of a family's most cherished artifacts. The same thing can be said of the Hubble Space Telescope and the infant stars it immortalizes in its scientific portraits. But while we know how babies are conceived and how they form in great detail, the same can't be said for star formation.

