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Finite-time prescribed performance control for the test mass release phase based on twistors

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Yu Zhang, Yuan Liu, Wenjian Tao, Hui Wang, Daixin Wang

Orbit determination for Chang’e-6 mission during the lunar orbit phase

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Jiachen Yuan, Yidan Huang, Peijia Li, Zhenghao Zhang, Yunlong Ma, Peng Yang, Yong Huang

Semi-analytical optimal control for spacecraft constrained hovering over tumbling object

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Zhan Feng, Xue Bai, Jun Jiang, Jun Zhu, Ming Xu

Improving GNSS ultra-rapid orbit accuracy via multi-session normal equation stacking

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Longjiang Tang, Jungang Wang, Zhiwei Qin, Bobin Cui, Huizhong Zhu

Angular momentum management strategies for deep space CubeSats and their application to EQUULEUS

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Hirotaka Sekine, Shunichiro Nomura, Riki Nakamura, Vinicius Nery, Toshihiro Suzuki, Ryohei Takahashi, Shintaro Nakajima, Yosuke Kawabata, Ryota Fuse, Ryu Funase

One-step estimation of earth gravity field from GRACE and ground-based GPS measurements combination

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Minxing Zhao, Xiancai Zou, Juanxia Pan, Luping Zhong, Han Liu, Jiancheng Li

Dilution of precision for LEO satellite precise orbit and clock determination

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Jiawei Liu, Kan Wang, Ahmed El-Mowafy, Chunbo Wei, Xuhai Yang

Hypersonic trajectory prediction based on partially observable information

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Fangjia Lian, Bangjie Li, Qisong Yang, Jiufen Zhao

UNet with multibranch prior information encoding for building segmentation in remote sensing images

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Yingbin Wu, Fubo Wang, Peng Zhao, Mingquan Zhou, Shengling Geng, Dan Zhang

An approach for good modeling and forecasting of sea surface salinity in a coastal zone using machine learning LASSO regression models built with sparse satellite time series datasets

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): Opeyemi Ajibola-James, Francis I. Okeke

OrbitTrack: Advanced RSO detection and tracking from wide field-of-view on-orbit images

Publication date: 15 October 2025

Source: Advances in Space Research, Volume 76, Issue 8

Author(s): YeonJeong Jeong, Vithurshan Suthakar, Randa Qashoa, Gunho Sohn, Regina S.K. Lee

Increasing heat is super-charging Arctic climate and weather extremes

Phys.org: Earth science - Tue, 10/21/2025 - 18:16
By evaluating historical climate records, observational and projection data, an international team of researchers found a "pushing and triggering" mechanism that has driven the Arctic climate system to a new state, which will likely see consistently increased frequency and intensity of extreme events across all system components—the atmosphere, ocean and cryosphere—this century.

Seismic anisotropy offers insight into viscous BLOBs at base of Earth's mantle

Phys.org: Earth science - Tue, 10/21/2025 - 16:57
In some parts of Earth's interior, seismic waves travel at different speeds depending on the direction in which they are moving through the layers of rock in Earth's interior. This property is known as seismic anisotropy, and it can offer important information about how the silicate rock of the mantle—particularly at the mantle's lowermost depths—deforms. In contrast, areas through which seismic waves travel at the same speed regardless of direction are considered isotropic.

Greenland's caves preserve an ancient climate archive

Phys.org: Earth science - Tue, 10/21/2025 - 14:07
In a remote cave in northern Greenland, a research team led by geologists Gina Moseley, Gabriella Koltai, and Jonathan Baker from the University of Innsbruck has discovered evidence of a significantly warmer Arctic. The cave deposits show that the region was free of permafrost millions of years ago and responded sensitively to rising temperatures.

To Find Critical Minerals, Look to Plate Tectonics

EOS - Tue, 10/21/2025 - 13:31

For much of the 20th century, “petroleum politics” shaped international policy. In the 21st century, a new set of resources has taken center stage: critical minerals. Sourcing and extracting these minerals have become a priority for countries and communities around the world because they are used in everything from solar panels to cell phones to superconductors.

A new study suggests where prospectors can search for critical minerals: rifting sites left behind by the supercontinent Rodinia, which broke up in the Proterozoic, more than 800 million years ago.

“To better find [critical] resources, really, we need a better understanding of geology.”

“Unless it is grown, absolutely everything on the planet that we use as a manufactured good requires something that comes out of a mine,” said Chris Kirkland, a geologist at Curtin University in Australia and a coauthor of the new study, published last month in Geological Magazine. “To better find those resources, really, we need a better understanding of geology.”

Kirkland and his colleagues began by analyzing rocks unearthed by drilling companies in Western Australia. The slabs contain carbonatite, a “weird,” rare, and poorly understood kind of igneous rock formed in the mantle from magmas rich in carbonate minerals. As the magmas rise through Earth’s interior, they react with surrounding rocks, altering the chemical signatures that geologists typically use to trace a sample’s origins.

Carbonatites often contain rare earth elements, such as niobium. Although niobium can be found in different rocks, carbonatites are the only ones offering it in amounts economically suitable for extraction. The Western Australia sites are home to more than 200 million metric tons of the metal.

The team “threw the whole kitchen sink of analytical techniques” at the carbonatites, explained Kirkland. The first step was to take a drill core sample and image its structure to see the broad geological ingredients inside. Then the researchers used lasers to sample individual grains and piece out their crystals.

The carbonatites contained zircon, apatite, and mica, all crystals with isotopes that decay at known rates and can tell researchers about the sample’s age and source. The researchers also analyzed the helium present in zircon, because helium is a volatile element that easily escapes rocks near the surface and can help reveal when the rocks reached the crust.

Written in Stone

The story written in the slabs is one tied to the long history of plate tectonics. The breakup of Rodinia began around 800 million years ago and continued for millions of years as hot, metal-enriched oozes of magma rose up from the mantle. Pressure from this rising rock helped split apart the supercontinent, and the metals encased in carbonatites breached the surface at once-stable mounds of continental crust called cratons.

Today, said Kirkland, tracking these “old fossil scars” where cratons split could reveal stores of minerals.

More than 200 million metric tons of niobium were recently identified in Australia’s Aileron Province, a likely result of the breakup of Rodinia. Credit: Dröllner et al., 2025, https://doi.org/10.1017/S0016756825100204

“Reconstructing a geologic history for one particular area on Earth is something that I think has potential to help us in better understanding these pretty poorly understood carbonatite systems globally,” said Montana State University geologist Zachary Murguía Burton, who was not involved with the paper.

Burton estimates that some 20% of the carbonatites on Earth contain economically attractive concentrations of critical minerals, although he noted that the rocks in the study experienced a unique confluence of local and regional geologic processes that might influence the minerals they contain.

In particular, the carbonatites analyzed in the new study identified the source of recently discovered niobium deposits beneath central Australia. Niobium is a critical mineral used in lithium-ion batteries and to strengthen and lighten steel. Because 90% of today’s supply of niobium comes from a single operation in Brazil, finding additional deposits is a priority.

In addition to niobium, Kirkland said a geologic “recipe” similar to the one his team identified might work for finding gold.

The work is an important reminder of “how tiny minerals and clever dating techniques can not only solve deep-time geological puzzles, but also help guide the hunt for the critical metals we need,” Kirkland said.

—Hannah Richter (@hannah-richter.bsky.social), Science Writer

Citation: Richter, H. (2025), To find critical minerals, look to plate tectonics, Eos, 106, https://doi.org/10.1029/2025EO250393. Published on 21 October 2025. Text © 2025. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Seismic Anisotropy Reveals Deep-Mantle Dynamics

EOS - Tue, 10/21/2025 - 13:31
Source: Geochemistry, Geophysics, Geosystems

In some parts of Earth’s interior, seismic waves travel at different speeds depending on the direction in which they are moving through the layers of rock in Earth’s interior. This property is known as seismic anisotropy, and it can offer important information about how the silicate rock of the mantle—particularly at the mantle’s lowermost depths—deforms. In contrast, areas through which seismic waves travel at the same speed regardless of direction are considered isotropic.

In the bottom 300 kilometers of the mantle, also known as the D’’ layer, anisotropy is potentially caused by mantle plumes or mantle flow interacting with the edges of large low-shear-velocity provinces: continent-sized, dense, hot BLOBs (big lower-mantle basal structures) at the base of the mantle above the core. Many questions persist about the viscosity, movement, stability, and shape of the BLOBS, as well as about how they can be influenced by mantle plumes and subduction.

Roy et al. used ASPECT, a 3D mantle convection modeling software, and ECOMAN, a mantle fabric simulation code, to examine the deep mantle. They tested five different mantle model configurations, adjusting the viscosity and density of the BLOBs. The goal was to see which configuration would most closely re-create the observed seismic anisotropy.

The researchers treated the BLOBs as regions with their own unique chemistry, which form from a 100-kilometer-thick layer at the bottom of the mantle. Their models simulated how mantle plumes formed over the past 250 million years, during which time events such as the breakup of Pangaea, the opening of the Atlantic, and the evolution of various subduction zones occurred.

The study suggests that the best explanation for observed seismic anisotropy is when the BLOBs are 2% denser and 100 times more viscous than the surrounding mantle. This aligns with observations of anisotropy patterns in seismic data. Plumes form mainly at the edges of BLOBs, where strong deformation causes strong anisotropy. (Geochemistry, Geophysics, Geosystems, https://doi.org/10.1029/2025GC012510, 2025)

—Rebecca Owen (@beccapox.bsky.social), Science Writer

Citation: Owen, R. (2025), Seismic anisotropy reveals deep-mantle dynamics, Eos, 106, https://doi.org/10.1029/2025EO250392. Published on 21 October 2025. Text © 2025. AGU. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Shifting waters: Climate change in Italy's mountains

Phys.org: Earth science - Tue, 10/21/2025 - 13:16
About 15% of Italy's energy is produced by its nearly 5,000 hydroelectric power plants. In the Valle dei Laghi region, water flowing from the surrounding mountains supports local agriculture and the Santa Massenza hydroelectric plant, which powers the entire Trentino province. But as climate change accelerates, this delicate equilibrium is shifting.

Traffic vibrations help scientists dig deep into Lake George's seismic past

Phys.org: Earth science - Tue, 10/21/2025 - 13:08
Scientists from The Australian National University (ANU) have analyzed signals generated by the vibrations of traffic along the Federal Highway to learn more about the seismic nature of Lake George, situated north-east of Canberra.

Solar radiation management is gaining traction as a climate intervention, but how hard is it to dim the sun?

Phys.org: Earth science - Tue, 10/21/2025 - 12:12
Once considered a fringe idea, the prospect of offsetting global warming by releasing massive quantities of sunlight-reflecting particles into Earth's atmosphere is now a matter of serious scientific consideration. Hundreds of studies have modeled how this form of solar geoengineering, known as stratospheric aerosol injection (SAI), might work.

Fire in the sky: Strong summer storms in the Midwest send wildfire smoke into the previously pristine stratosphere

Phys.org: Earth science - Tue, 10/21/2025 - 11:34
Gully washer. Duck drownder. Toad strangler. Cob floater. Sod soaker. Whatever their names, summer in the Midwest isn't summer without strong, sudden storms with towering clouds. While the Indian subcontinent is famous for its monsoon season, what many people don't know is that the midwestern United States has its own monsoon season, very nearly as strong.

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