Tag

Gnss

All articles tagged with #gnss

science29 days ago•15 min saved

US Overhauls Geodetic Backbone, Rebaselining Coordinates by Up to Four Meters

The National Geodetic Survey is retiring NAD83 (horizontal) and NAVD88 (vertical) and replacing them with four plate-fixed terrestrial reference frames plus a new geopotential datum, tying coordinates to GEOID2022 and the ITRF2020. As a result, every published latitude, longitude and height could shift by up to about four meters depending on location and epoch, even though the actual ground stays fixed. Submissions to the old system end January 13, 2027, and control moves off the ground into orbit, with epoch 2020.00 referenced in the new system. Old survey marks remain in records but won’t serve as primary geodetic control, and downstream products like flood maps will be affected. The transition will require new software and may prompt state-law updates as federal agencies align with international standards and satellite positioning.

via Space Daily|

#geodesy #geodetic-datum #gnss

science3 months ago•6 min saved

Core-reflected seismic pulse may have nudged Japan after the 2011 megathrust quake

Analysis of Japan’s GNSS data from the 2011 magnitude-9.0 Tōhoku earthquake suggests a seismic wave returning from the core–mantle boundary (ScS) may have triggered a broad, millimeter-to-centimeter fault slip across a large plate boundary, producing tiny but detectable eastward shifts and an energy release comparable to a magnitude 7.5 quake, potentially the first known example of wave-triggered slip from a core-reflected seismic wave; findings published in Science.

via ScienceAlert|

#core-mantle-boundary #fault-slip #gnss

technology4 months ago•6 min saved

Russia’s Space-Based GPS Jamming Confirmed by Independent Research

UT Austin researchers, corroborated by others from the UK, used data from 165 GNSS reference stations to confirm that Russia has been jamming GPS from space since 2019 via a small Molniya-orbit satellite constellation, causing short, powerful disruptions on the L1 band (up to about 10 dB CNr) and also impacting BeiDou. The 2025 study and a May 2026 preprint argue the pattern is intentional rather than a malfunction. The findings underscore GNSS vulnerabilities, spur terrestrial backup efforts by several countries, and highlight policy and strategic implications for space-based EW in great-power competition.

via SpaceNews|

#gnss #gps #jamming

technology7 months ago•6 min saved

GPS Jamming Sparks Hidden Maritime Risk in the Gulf

GPS jamming off Iran is creating AIS position distortions near the Strait of Hormuz, making vessels appear on land or in strange clusters and raising collision risks as electronic warfare spills into Gulf waters. While Iran is suspected, there is no official confirmation; researchers use radar and satellite data to map the interference and are pursuing mitigations from anti-jamming antennas to alternative navigation methods (gyroscopes, accelerometers, star-mapping), though no solution is perfect. The episode highlights the vulnerability of open GNSS and the push toward more secure, multi-sensor positioning.

via BBC|

#ais #gnss #gps

space7 months ago•9 min saved

Mars Global Localization Gives Perseverance GPS-like Autonomy

NASA's JPL repurposed Perseverance's Helicopter Base Station to run a terrain-based localization algorithm that compares the rover's navigation-camera panoramas with onboard Mars terrain maps, delivering GPS-like positioning and enabling more autonomous navigation without constant Earth-based guidance. The test used the faster HBS hardware and found RAM bit faults, which were isolated to keep the algorithm reliable, showcasing Ingenuity-era hardware enabling new capabilities for the rover.

via Hackaday|

#gnss #mars #nasa-jpl

science1 year ago•3 min saved

South Africa's Land Is Rising Out of the Ocean, Scientists Discover Why

Scientists have discovered that South Africa's land is rising up to 2 millimeters per year, primarily due to drought-induced water loss, challenging previous mantle flow explanations. This finding, supported by GNSS and satellite data, highlights the impact of climate change on Earth's crust and offers a potential new method for monitoring water scarcity.,

via ScienceAlert|

#climate-change #gnss #land-uplift

science-and-technology3 years ago•3 min saved

NASA Detects Tsunamis Through Atmospheric Rumbles

NASA's Jet Propulsion Laboratory is testing a new system called GUARDIAN that uses data from GPS and other wayfinding satellites to detect tsunamis by analyzing the low-frequency sound and gravity waves created by the displacement of air above the ocean's surface. The system can produce a snapshot of a tsunami's rumble reaching the ionosphere within 10 minutes and could potentially provide up to an hour of warning. GUARDIAN is currently focused on the Pacific Ocean's Ring of Fire, where 78% of confirmed tsunamis between 1900 and 2015 occurred. The system aims to complement existing ground- and ocean-based instruments for faster tsunami detection.

via NASA Jet Propulsion Laboratory|

#early-warning #gnss #nasa