Geodesy

Geodesy is the science of accurately measuring the geometric shape of the earth, its orientation in space, and its gravity field, and monitoring how these properties change over time. Space geodesy is the geodesy that is practiced using extra-terrestrial assets such as satellites and quasars.

Haystack scientists and engineers focus on two aspects of space geodesy: geodetic VLBI, or measuring positions on the earth and the earth’s rotation and orientation, and polar geodesy, or measuring polar ice in the Arctic and Antarctic.

Spotlight Projects

SIDEx: Sea Ice Dynamic Experiment

Measuring ice in the Arctic Circle.

SGIP: Antarctic Seismo-Geodetic Ice Penetrator

Monitoring the response of ice shelves in Antarctica to ocean forces.

Advancing VGOS

The Haystack VLBI Geodetic Observing System (VGOS) signal chain has been in development since 2007 and in service since 2010. It was developed for NASA and has been installed in Texas and Hawaii.

All Geodesy Projects

Haystack geodesy

Geodetic VLBI

Our geodesy teams use a technique pioneered at Haystack in the 1960s called very long baseline interferometry (VLBI). VLBI allows data from pairs of telescopes all across the globe to be combined, resulting in measurements much more precise than those of a single telescope. VLBI is widely used for many scientific applications (such as taking images of black holes!) in addition to geodesy. Haystack’s space geodesy program develops technologies and makes observations for precisely calculating Universal Time, or UT1, based on the earth’s rotation speed and angle. These measurements are essential for keeping GPS and other global navigation systems accurate.

Polar geodesy

Our polar geodesy program develops high-precision GPS instruments to study glaciers, icebergs, sea ice, and ice shelves in the Arctic and Antarctic. Data from these installations are relayed back to Haystack by satellites for analysis. Knowing where and how the polar ice is melting, drifting, deforming, and fracturing is crucial for cryosphere, oceanography, and climate science studies.

Researchers

John Barrett

Christopher Eckert

Pedro Elosegui

Dhiman R. Mondal

Arthur Niell

Ganesh Rajagopalan

Chester A. Ruszczyk

Recent Publications

THEMIS: A Parameter Estimation Framework for the Event Horizon Telescope. The Astrophysical Journal. (2020). DOI: https://doi.org/10.3847/1538-4357/ab91a4

Verification of Radiative Transfer Schemes for the EHT. The Astrophysical Journal. (2020). DOI: https://doi.org/10.3847/1538-4357/ab96c6

SYMBA: An end-to-end VLBI synthetic data generation pipeline. arXiv e-prints. (2020). BIBCODE: https://ui.adsabs.harvard.edu/abs/2020arXiv200401161R

All publications