Space geodesy The focus of the FGI's space geodesy group is on various space geodetic and astronomical observing techniques covering different wavelengths: from very long baseline inteferometry (VLBI) and radar, to satellite laser ranging (SLR) and passive optical observations. In addition, the remote sensing techniques are complemented by laboratory measurements. Our research topics range from fundamental electromagnetic scattering processes and different inverse problems for both natural and artificial space objects, to quasar source structure.
Small Solar System objects We have developed and evaluated an automated processing pipeline applicable to optical observations of moving objects, such as space debris or asteroids. The pipeline is capable of detecting streaks in single images (as compared to consecutive frames of the same field) obtained with any observing scenario, including space-based surveys and both low- and high-altitude populations. In addition to this we model processes accompanying the object's entry into the planetary atmosphere and extract its physical parameters and the pre-impact Solar System orbit based on observations. We have demonstrated the application of the model using a wide range of observational data from meteorite-producing fireballs appearing annually (such as Annama and Košice) to larger scale impacts (such as Chelyabinsk, Sikhote-Alin and Tunguska). Meteor studies are conducted in close collaboration with the Finnish Fireball Network.
Laser scanning New developments in mobile laser scanning (MLS) provide potential to acquire rapidly topographic information of impact craters, dune formations and river bedforms at the resolution of grain-scale upwards. The MLS research at FGI aims at developing an integrated methodology to quantify morphodynamic changes on rivers at reach-scale, and to explore new opportunities for applications in quantification of e.g. morphometric analysis and sediment budgeting but also for modeling and analysis of impact craters. Further possibilities may be found in adapting the systems to planetary analog missions.
Spectropolarimetric measurements of various targets under laboratory and actual field conditions are carried out using the Finnish Geodetic Institute's field goniospectrometer, FIGIFIGO. The design concept of this custom made instrument has proven to have a number of advantages, such as a well designed, user friendly interface, a high level of automation, and an excellent adaptability to a wide range of weather conditions during field measurements. FIGIFIGO has been used to measure the reflectance properties of hundreds of different targets, such as snow, various types of vegetation, meteorites, planetary analogues, sand, gravel, as well as many man-made targets. The potential use of the results from these measurements are diverse; including their use as ground truth references for remote sensing and astrobiology studies, testing and validation of theoretical scattering models, estimating climate change over time, measuring other ecological effects caused by changes in land cover, and more generally, to aid in the identification and analysis of both seasonal, and nonseasonal variations of targets of interest.