Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: asteroid/comet impacts

Supernova immersion model suggests Earth-like planets are more common in the universe

Rocky planets like our Earth may be far more common than previously thought, according to new research published in the journal Science Advances. It suggests that when our solar system formed, a nearby supernova (the massive explosion of a star near the end of its life) bathed it in cosmic rays containing the radioactive ingredients to make rocky, dry worlds. This mechanism could be ubiquitous across the galaxy.

Earth-like planets are thought to form from planetesimals (objects made of rock and ice) that were dried out early in the solar system’s history. This process required a lot of heat, which came primarily from the radioactive decay of short-lived radionuclides (SLRs), such as aluminum-26. Previous analysis of meteorites, which are ancient records of the early solar system, confirmed the abundance of SLRs at this time.

Flaws in previous models However, models that explain supernovae as the sole source of these SLRs cannot accurately match the quantity of the nucleotides found in meteorites. To deliver enough radioactive material, the supernova would have to be so close to the early solar system that it would have destroyed the disk of dust and gas where the planets were forming.

Hubble captures rare collision in nearby planetary system

In an unprecedented celestial event, NASA’s Hubble Space Telescope (HST) captured the dramatic aftermath of colliding space rocks within a nearby planetary system.

When astronomers initially spotted a bright object in the sky, they assumed it was a dust-covered exoplanet, reflecting starlight. But when the “exoplanet” disappeared and a new bright object appeared, the international team of astrophysicists—including Northwestern University’s Jason Wang—realized these were not planets at all. Instead, they were the illuminated remains of a cosmic fender bender.

Two distinct, violent collisions generated two luminous clouds of debris in the same planetary system. The discovery offers a unique real-time glimpse into the mechanisms of planet formation and the composition of materials that coalesce to form new worlds.

A volcano or a meteorite? New evidence sheds light on puzzling discovery in Greenland’s ice sheet

Buried deep in Greenland’s ice sheet lies a puzzling chemical signature that has sparked intense scientific debate. A sharp spike in platinum concentrations, discovered in an ice core (a cylinder of ice drilled out of ice sheets and glaciers) and dated to around 12,800 years ago, has provided support for a hypothesis that Earth was struck by an exotic meteorite or comet at that time.

Our new research published in PLOS One offers a much more mundane explanation: this mystery signature may have originated from a volcanic fissure eruption in Iceland, not space.

The timing matters. The platinum spike occurs near the beginning of our planet’s last great cold period, the Younger Dryas Event. This lasted from about 12,870 to 11,700 years ago and saw temperatures plummet across the northern hemisphere.

Geologists discover the first evidence of 4.5-billion-year-old ‘proto Earth’

Scientists at MIT and elsewhere have discovered extremely rare remnants of “proto Earth,” which formed about 4.5 billion years ago, before a colossal collision irreversibly altered the primitive planet’s composition and produced Earth as we know today. Their findings, reported today in the journal Nature Geosciences, will help scientists piece together the primordial starting ingredients that forged early Earth and the rest of the solar system.

Billions of years ago, the early solar system was a swirling disk of gas and dust that eventually clumped and accumulated to form the earliest meteorites, which in turn merged to form proto Earth and its neighboring planets.

In this earliest phase, Earth was likely rocky and bubbling with lava. Then, less than 100 million years later, a Mars-sized meteorite slammed into the infant planet in a singular “giant impact” event that completely scrambled and melted the planet’s interior, effectively resetting its chemistry. Whatever original material proto Earth was made from was thought to have been altogether transformed.

Gaia solves mystery of tumbling asteroids and finds new way to probe their interiors

Whether an asteroid is spinning neatly on its axis or tumbling chaotically, and how fast it is doing so, has been shown to be dependent on how frequently it has experienced collisions. The findings, presented at the recent EPSC-DPS2025 Joint Meeting in Helsinki, are based on data from the European Space Agency’s Gaia mission and provide a means of determining an asteroid’s physical properties—information that is vital for successfully deflecting asteroids on a collision course with Earth.

“By leveraging Gaia’s unique dataset, advanced modeling and A.I. tools, we’ve revealed the hidden physics shaping rotation, and opened a new window into the interiors of these ancient worlds,” said Dr. Wen-Han Zhou of the University of Tokyo, who presented the results at EPSC-DPS2025.

During its survey of the entire sky, the Gaia mission produced a huge dataset of asteroid rotations based on their light curves, which describe how the light reflected by an asteroid changes over time as it rotates. When the asteroid data is plotted on a graph of the rotation period versus diameter, something startling stands out—there’s a gap, or dividing line that appears to split two distinct populations.

Mars Perseverance rover data suggests presence of past microbial life

A new study co-authored by Texas A&M University geologist Dr. Michael Tice has revealed potential chemical signatures of ancient Martian microbial life in rocks examined by NASA’s Perseverance rover.

The findings, published by a large international team of scientists, focus on a region of Jezero Crater known as the Bright Angel formation—a name chosen from locations in Grand Canyon National Park because of the light-colored Martian rocks. This area in Mars’s Neretva Vallis channel contains fine-grained mudstones rich in oxidized iron (rust), phosphorus, sulfur and—most notably—organic carbon. Although organic carbon, potentially from non-living sources like meteorites, has been found on Mars before, this combination of materials could have been a rich source of energy for early microorganisms.

“When the rover entered Bright Angel and started measuring the compositions of the local rocks, the team was immediately struck by how different they were from what we had seen before,” said Tice, a geobiologist and astrobiologist in the Department of Geology and Geophysics.

‘Invisible’ asteroids near Venus may threaten Earth in the future

An international study led by researchers at São Paulo State University (UNESP) in Brazil has identified a little-known but potentially significant threat: Asteroids that share Venus’s orbit and may completely escape current observational campaigns because of their position in the sky. These objects have not yet been observed, but they could strike Earth within a few thousand years. Their impacts could devastate large cities.

“Our study shows that there’s a population of potentially dangerous asteroids that we can’t detect with current telescopes. These objects orbit the sun, but aren’t part of the asteroid belt, located between Mars and Jupiter. Instead, they’re much closer, in resonance with Venus. But they’re so difficult to observe that they remain invisible, even though they may pose a real risk of collision with our planet in the distant future,” astronomer Valerio Carruba, a professor at the UNESP School of Engineering at the Guaratinguetá campus (FEG-UNESP) and first author of the study, told Agência FAPESP.

The study is published in the journal Astronomy & Astrophysics. The work combined analytical modeling and long-term to track the dynamics of these objects and assess their potential to come dangerously close to Earth.

/* */