“Our study shows that the environmental resilience of S. caninervis is superior to that of some of highly stress-tolerant microorganisms and tardigrades,” write the researchers, who include ecologists Daoyuan Zhang and Yuanming Zhang and botanist Tingyun Kuang of the Chinese Academy of Sciences. “S. caninervis is a promising candidate pioneer plant for colonizing extraterrestrial environments, laying the foundation for building biologically sustainable human habitats beyond Earth.”

A small number of previous studies have tested the ability of microorganisms, algae, lichens, and plant spores to withstand the extreme environments of outer space or Mars, but this is the first study to test whole plants.

Syntrichia caninervis is a common moss species with a widespread global distribution. It grows in remarkably extreme desert environments including Tibet, Antarctica, and the circumpolar regions as part of the biological soil crust — a widespread and resilient type of ground cover often found in arid lands. Given the moss’s ability to survive extreme environmental conditions, the researchers decided to test its limits in the lab.

To test the moss’s cold tolerance, the researchers stored plants at −80°C (in an ultra-cold freezer) for 3 and 5 years and at −196°C (in a liquid nitrogen tank) for 15 and 30 days. In all cases, the plants regenerated when they were defrosted, though their rebound was less rapid compared to control specimens that had been dehydrated but not frozen, and plants that were not dehydrated prior to freezing rebounded more slowly than plants that were dried, then frozen.

The moss also demonstrated the ability to survive gamma radiation exposure that would kill most plants, and doses of 500 Gy even seemed to promote the plants’ growth. For comparison, humans experience severe convulsions and death when exposed to around 50 Gy. “Our results indicate that S. caninervis is among the most radiation-tolerant organisms known,” the researchers write.

Finally, the researchers tested the moss’s ability to endure Mars-like conditions using the Chinese Academy of Sciences’ Planetary Atmospheres Simulation Facility. The simulator’s Martian conditions included air composed of 95% CO₂, temperatures that fluctuated from −60°C to 20°C, high levels of UV radiation, and low atmospheric pressure. Dried moss plants achieved a 100% regeneration rate within 30 days after being subjected to the Martian conditions for 1, 2, 3, and 7 days. Hydrated plants, which were only subjected to the simulator for one day, also survived, though they regenerated more slowly than their desiccated counterparts.

“Although there is still a long way to go to create self-sufficient habitats on other planets, we demonstrated the great potential of S. caninervis as a pioneer plant for growth on Mars,” the researchers write. “Looking to the future, we expect that this promising moss could be brought to Mars or the Moon to further test the possibility of plant colonization and growth in outer space.”

This research was supported by the Chinese Academy of Sciences, the Leading Talents in Technological Innovation Program, and The Third Xinjiang Scientific Expedition Program.

At water depths greater than 3,000 meters, the remote-controlled submersible vehicle MARUM-QUEST took samples from the newly discovered hydrothermal field. Named after Jøtul, a giant in Nordic mythology, the field is located on the 500-kilometer-long Knipovich Ridge. The ridge lies within the triangle formed by Greenland, Norway and Svalbard on the boundary of the North American and European tectonic plates. This kind of plate boundary, where two plates move apart, is called a spreading ridge. The Jøtul Field is located on an extremely slow spreading ridge with a growth rate of the plates of less than two centimeters per year. Because very little is known about hydrothermal activity on slow spreading ridges, the expedition focused on obtaining an overview of the escaping fluids, as well as the size and composition of active and inactive smokers in the field.

“The Jøtul Field is a discovery of scientific interest not only because of its location in the ocean but also due to its climate significance, which was revealed by our detection of very high concentrations of methane in the fluid samples, among other things,” reports Gerhard Bohrmann. Methane emissions from hydrothermal vents indicate a vigorous interaction of magma with sediments. On its journey through the water column, a large proportion of the methane is converted into carbon dioxide, which increases the concentration of CO₂ in the ocean and contributes to acidification, but it also has an impact on climate when it interacts with the atmosphere. The amount of methane from the Jøtul Field that eventually escapes directly into the atmosphere, where it then acts as a greenhouse gas, still needs to be studied in more detail. There is also little known about the organisms living chemosynthetically in the Jøtul Field. In the darkness of the deep ocean, where photosynthesis cannot occur, hydrothermal fluids form the basis for chemosynthesis, which is employed by very specific organisms in symbiosis with bacteria.

In order to significantly expand on the somewhat sparse information available on the Jøtul Field, a new expedition of the MARIA S. MERIAN will start in late summer of this year under the leadership of Gerhard Bohrmann. The focus of the expedition is the exploration and sampling of as yet unknown areas of the Jøtul Field. With extensive data from the Jøtul Field it will be possible to make comparisons with the few already known hydrothermal fields in the Arctic province, such as the Aurora Field and Loki’s Castle.

An international team, led by Penn State researchers, using the NIRSpec instrument aboard JWST as part of the RUBIES survey identified three mysterious objects in the early universe, about 600-800 million years after the Big Bang, when the universe was only 5% of its current age. They announced the discovery today (June 27) in Astrophysical Journal Letters.

The team studied spectral measurements, or intensity of different wavelengths of light emitted from the objects. Their analysis found signatures of “old” stars, hundreds of millions of years old, far older than expected in a young universe.

The researchers said they were also surprised to discover signatures of huge supermassive black holes in the same objects, estimating that they are 100 to 1,000 times more massive than the supermassive black hole in our own Milky Way. Neither of these are expected in current models of galaxy growth and supermassive black hole formation, which expect galaxies and their black holes to grow together over billions of years of cosmic history.

“We have confirmed that these appear to be packed with ancient stars — hundreds of millions of years old — in a universe that is only 600-800 million years old. Remarkably, these objects hold the record for the earliest signatures of old starlight,” said Bingjie Wang, a postdoctoral scholar at Penn State and lead author on the paper. “It was totally unexpected to find old stars in a very young universe. The standard models of cosmology and galaxy formation have been incredibly successful, yet, these luminous objects do not quite fit comfortably into those theories.”

The researchers first spotted the massive objects in July of 2022, when the initial dataset was released from JWST. The team published a paper in Nature several months later announcing the objects’ existence.

At the time, the researchers suspected the objects were galaxies, but followed up their analysis by taking spectra to better understand the true distances of the objects, as well as the sources powering their immense light.

The researchers then used the new data to draw a clearer picture of what the galaxies looked like and what was inside of them. Not only did the team confirm that the objects were indeed galaxies near the beginning of time, but they also found evidence of surprisingly large supermassive black holes and a surprisingly old population of stars.

“It’s very confusing,” said Joel Leja, assistant professor of astronomy and astrophysics at Penn State and co-author on both papers. “You can make this uncomfortably fit in our current model of the universe, but only if we evoke some exotic, insanely rapid formation at the beginning of time. This is, without a doubt, the most peculiar and interesting set of objects I’ve seen in my career.”

The JWST is equipped with infrared-sensing instruments capable of detecting light that was emitted by the most ancient stars and galaxies. Essentially, the telescope allows scientists to see back in time roughly 13.5 billion years, near the beginning of the universe as we know it, Leja said.

One challenge to analyzing ancient light is that it can be hard to differentiate between the types of objects that could have emitted the light. In the case of these early objects, they have clear characteristics of both supermassive black holes and old stars. However, Wang explained, it’s not yet clear how much of the observed light comes from each — meaning these could be early galaxies that are unexpectedly old and more massive even than our own Milky Way, forming far earlier than models predict, or they could be more normal-mass galaxies with “overmassive” black holes, roughly 100 to 1,000 times more massive than such a galaxy would have today.

“Distinguishing between light from material falling into a black hole and light emitted from stars in these tiny, distant objects is challenging,” Wang said. “That inability to tell the difference in the current dataset leaves ample room for interpretation of these intriguing objects. Honestly, it’s thrilling to have so much of this mystery left to figure out.”

Aside from their unexplainable mass and age, if part of the light is indeed from supermassive black holes, then they also aren’t normal supermassive black holes. They produce far more ultraviolet photons than expected, and similar objects studied with other instruments lack the characteristic signatures of supermassive black holes, such as hot dust and bright X-ray emission. But maybe the most surprising thing, the researchers said, is how massive they seem to be.

“Normally supermassive black holes are paired with galaxies,” Leja said. “They grow up together and go through all their major life experiences together. But here, we have a fully formed adult black hole living inside of what should be a baby galaxy. That doesn’t really make sense, because these things should grow together, or at least that’s what we thought.”

The researchers were also perplexed by the incredibly small sizes of these systems, only a few hundred light years across, roughly 1,000 times smaller than our own Milky Way. The stars are approximately as numerous as in our own Milky Way galaxy — with somewhere between 10 billion and 1 trillion stars — but contained within a volume 1,000 times smaller than the Milky Way.

Leja explained that if you took the Milky Way and compressed it to the size of the galaxies they found, the nearest star would almost be in our solar system. The supermassive black hole in the center of the Milky Way, about 26,000 light years away, would only be about 26 light years away from Earth and visible in the sky as a giant pillar of light.

“These early galaxies would be so dense with stars — stars that must have formed in a way we’ve never seen, under conditions we would never expect during a period in which we’d never expect to see them,” Leja said. “And for whatever reason, the universe stopped making objects like these after just a couple of billion years. They are unique to the early universe.”

The researchers are hoping to follow up with more observations, which they said could help explain some of the objects’ mysteries. They plan to take deeper spectra by pointing the telescope at the objects for prolonged periods of time, which will help disentangle emission from stars and the potential supermassive black hole by identifying the specific absorption signatures that would be present in each.

“There’s another way that we could have a breakthrough, and that’s just the right idea,” Leja said. “We have all these puzzle pieces and they only fit if we ignore the fact that some of them are breaking. This problem is amenable to a stroke of genius that has so far eluded us, all of our collaborators and the entire scientific community.”

Wang and Leja received funding from NASA’s General Observers program. The research was also supported by the International Space Science Institute in Bern. The work is based in part on observations made with the NASA/ESA/CSA James Webb Space Telescope. Computations for the research were performed on Penn State’s Institute for Computational and Data Sciences’ Roar supercomputer.

Other co-authors on the paper are Anna de Graaff of the Max-Planck-Institut für Astronomie in Germany; Gabriel Brammer of the Cosmic Dawn Center and Niels Bohr Institute; Andrea Weibel and Pascal Oesch of the University of Geneva; Nikko Cleri, Michaela Hirschmann, Pieter van Dokkum and Rohan Naidu of Yale University; Ivo Labbé of Stanford University; Jorryt Matthee and Jenny Greene of Princeton University; Ian McConachie and Rachel Bezanson of the University of Pittsburgh; Josephine Baggen of Texas A&M University; Katherine Suess of the Observatoire de Sauverny in Switzerland; David Setton of Massachusetts Institute of Technology’s Kavli Institute for Astrophysics and Space Research; Erica Nelson of the University of Colorado; Christina Williams of the U.S. National Science Foundation’s National Optical-Infrared Astronomy Research Laboratory and the University of Arizona.