GNSS Hotspots | April 2017 - Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design

GNSS Hotspots | April 2017

One of 12 magnetograms recorded at Greenwich Observatory during the Great Geomagnetic Storm of 1859
1996 soccer game in the Midwest, (Rick Dikeman image)
Nouméa ground station after the flood
A pencil and a coffee cup show the size of NASA’s teeny tiny PhoneSat
Bonus Hotspot: Naro Tartaruga AUV
Pacific lamprey spawning (photo by Jeremy Monroe, Fresh Waters Illustrated)
“Return of the Bucentaurn to the Molo on Ascension Day”, by (Giovanni Antonio Canal) Canaletto
The U.S. Naval Observatory Alternate Master Clock at 2nd Space Operations Squadron, Schriever AFB in Colorado. This photo was taken in January, 2006 during the addition of a leap second. The USNO master clocks control GPS timing. They are accurate to within one second every 20 million years (Satellites are so picky! Humans, on the other hand, just want to know if we’re too late for lunch) USAF photo by A1C Jason Ridder.
Detail of Compass/ BeiDou2 system diagram
Hotspot 6: Beluga A300 600ST

Antarctic Peninsula

Antarctic Peninsula
√ The “Antarctic oasis” is how polar researchers refer to the north end of James Ross Island, which at the extreme northern tip of the Antarctic Peninsula, is shielded from storms by the Trinity Mountains. For researchers at the Johan Gregor Mendel Research Station located on the Ulu Peninsula at the far north end of the island, the time and resources available for accurate positioning are limited, therefore, the processes to capture positions must be simple, efficient and combine readily with the scientific activities. One of the most important uses of GNSS at the Mendel Polar Station is for monitoring glaciers. Scientists are studying four glaciers on the island within 15 kilometers of the station. On three glaciers, networks of bamboo rods are installed into the ice at regular intervals. Researchers use GNSS to measure the 3D position at the base of each rod. They also measured the distance from the top of the bamboo to the ice surface. The data collected will support months and years of processing and analysis. Plans are already underway for future visits by Czech teams to James Ross Island.

Wageningen, The Netherlands
√ This E-Track project uses the European Geostationary Navigation Overlay Service (EGNOS) to provide higher accuracy locations than in conventional GPS animal tracking. It developed GPS animal tracking and analysis tools for sophisticated behavioral research on wild and domestic animals and focuses on enhanced accuracy, combined with fast sampling, sensors and a wide range of tag formats, sizes and remote communication systems.
The system is validated in field studies with mammals and large birds and uses devices enhanced by using the EGNOS augmentation system. The different GPS tags, either implemented as backpacks (birds) and collars (mammals) collect raw GPS signals to either calculate high precision “on board” or in post processing mode. GPS + EGNOS provides submeter accuracy. The devices developed in E-Track also include 3D accelerometers, necessary for the distinguishing behaviors with almost similar spatial patterns. It features a tracking software solution that is marketed via Noldus Information Technology, and the E-Track is carried out in the context of the Galileo FP7 R&D program supervised by the European GNSS Agency.

Reykjavík, Iceland
√ New research, with lead authors from the University of Gothenburg, gives indications of the best places in Iceland to build thermal power stations. In Iceland, heat is extracted for use in power plants directly from the ground in volcanic areas. Constructing a geothermal power station near a volcano can be beneficial, since Earth’s mantle is located relatively close to the crust in those areas, making the heat easily accessible. But placing a power plant near an active volcano is not without risk, as an eruption can easily destroy any human-made construction in its way.

The scientists have now studied three different parts of the divergent ridge (area where the ocean plates are slowly sliding away from each other) that crosses Iceland from southwest to northeast. The slow movement and separation of the ocean plates can cause cracks in Earth’s crust, through which hot magma from the planet’s interior rises to the surface. As a result, many volcanos have emerged along the divergent boundary. Using a geodetic GPS, the scientists have now been able to measure the movement of the plates over time. The data used in the study is based on measurements from almost 100 “fixed” measurement points. The information from the measurement points have made it possible to draw maps that show in what way the plates are moving away from each other and how large the deformation zone is.

Symonston, Australia
√ Australia is indeed on the move, with the Pacific tectonic plate moving in a northeasterly direction by about seven centimeters each year. As of January 2017, Australia’s coordinates have officially moved 1.8 meters northeast, following the launch of the Geocentric Datum of Australia 2020 (GDA2020). The first update to Australia’s coordinate system in two decades, GDA2020 is a step towards modernizing Australia’s spatial referencing system.

The work of Australia’s experts from Geoscience Australia and the Intergovernmental Panel on Surveying and Mapping (ICSM) are behind the move to GDA2020; Australia is one of the first countries in the world to make the ambitious move towards a dynamic datum. It will have the valuable role of supporting future positioning needs for applications like driverless vehicles and centimeter-accurate personal navigation. Australia’s current datum GDA94, like most other national datums the world over, adopts an epoch to define the datum and is expected to differ over time from the ITRF datum used by satellite navigation systems like GPS.