scholarly journals SPATS - A SOUTH POLE ACOUSTIC TEST SETUP

2006 ◽  
Vol 21 (supp01) ◽  
pp. 221-226 ◽  
Author(s):  
◽  
SEBASTIAN BÖSER ◽  
S. BÖSER ◽  
C. BOHM ◽  
S. HUNDERTMARK ◽  
...  

Due to its large Greeneisen coefficient ice is of special interest for the acoustic detection of ultra-high energetic neutrino-induced cascades. The abundant homogeneous volume and an existing neutrino observatory make the south polar ice cap a favourable location for this purpose. Theoretical calculations yield absorption lengths of ~ 10 km, but no measurements at all are available in the frequency range of interest. We present an experimental setup to measure the key parameters of the antarctic glacial ice.

2019 ◽  
Vol 46 (13) ◽  
pp. 7268-7277 ◽  
Author(s):  
Patricio Becerra ◽  
Michael M. Sori ◽  
Nicolas Thomas ◽  
Antoine Pommerol ◽  
Emanuele Simioni ◽  
...  

Polar Record ◽  
2019 ◽  
Vol 55 (6) ◽  
pp. 392-401
Author(s):  
Rip Bulkeley

AbstractThere has been some uncertainty as to which of the two southerly probes, during which Bellingshausen passed latitude 69°S in early 1820, achieved the first sighting of an ice coast of Dronning Maud Land in Eastern Antarctica. The author criticizes Frank Debenham’s English translation of Bellingshausen’s narrative before presenting and discussing new translations of Bellingshausen’s descriptions of those events, with relevant sections of his track chart, plus a third passage from the book which interpreted what was seen. He concludes that the Russians first sighted an ice coast in mid-February, rather than late January as has been widely claimed.


2021 ◽  
Author(s):  
Giacomo Di Silvestro ◽  
Roberto Orosei ◽  
Luca Guallini ◽  
Andrea Morelli

<p>The ESA Mars Express mission was launched in June 2003 and reached Martian orbit in December of the same year. Among the instruments onboard, the Italian-American radar MARSIS has retrieved valuable data, therefore contributing many discoveries related to the Red Planet, such as the evidence of sub-glacial water lakes beneath the South Pole of Mars. The technique used by this antenna is the radar echo sounding which, thanks to the electromagnetic waves emitted at frequencies in the HF range – in four separate bands centered at 1.8, 3, 4, and 5 MHz - has the ability to penetrate the ice masses, allowing the study of the internal properties and structures of glaciers and the regolith underneath.<br>Based on selected MARSIS radargrams, the main purpose of our analysis is to define the topography and main morphologies of the bedrock beneath Ultimi Lobe, part of the South Polar Ice Cap. Geologically speaking, this region is characterized by the South Polar Layered Deposits unit, widely showing complex layering and locally broad deformational structures (i.e., faults and folds). In particular, through the use of a georeferenced model of the bedrock surface, we focused on the search for low-topographies possibly consistent with basins able to contain the subglacial water reservoirs inferred by Orosei et al. (2018) and Lauro et al. (2020). Furthermore, we are implementing an algorithm focused on semi-automatic surface delineation using radar echo observations. Through the implementation of this script and retrieved data/images, we suggest that the machine-learning algorithm could be trained for further analysis.</p>


1975 ◽  
Vol 15 (73) ◽  
pp. 39-48 ◽  
Author(s):  
W. J. Fitzgerald ◽  
J. G. Paren

AbstractTwo 0.5 m cores from "Byrd" station, Antarctica have been studied in the laboratory, one from a shallow depth (155 m) and the other from the zone where recrystallization has given a vertical c-axis fabric, and the air in situ is thought to be in clathrate form (1 424 m). The dielectric response has been studied in the frequency range 60 Hz to 10 kHz, and in the temperature range — 6° C to —6o° C. The behaviour observed is markedly different from that of "pure" polycrystalline ice such as may be made by slowly freezing distilled de-ionized water and is thus at variance with the conclusions of Rogers (unpublished) who deduced, from measurements of the admittance of a dipole probe lowered through the fluid-filled drill hole at "Byrd", that the ice surrounding the hole had a dielectric response similar to that of "pure" ice. The Antarctic ice is shown to have properties similar to those of the ice from "Camp Century" and "Site 2" in Greenland studied by Paren (1973). In an attempt to discover what factors determine the difference in electrical behaviour between polar ice and pure ice, some samples were melted and subsequently refrozen slowly. Their dielectric response was similar to that of pure polycrystalline ice. These results are discussed in connection with the impurity content and growth conditions of the ices.


1975 ◽  
Vol 15 (73) ◽  
pp. 39-48 ◽  
Author(s):  
W. J. Fitzgerald ◽  
J. G. Paren

AbstractTwo 0.5 m cores from "Byrd" station, Antarctica have been studied in the laboratory, one from a shallow depth (155 m) and the other from the zone where recrystallization has given a verticalc-axis fabric, and the airin situis thought to be in clathrate form (1 424 m). The dielectric response has been studied in the frequency range 60 Hz to 10 kHz, and in the temperature range — 6° C to —6o° C. The behaviour observed is markedly different from that of "pure" polycrystalline ice such as may be made by slowly freezing distilled de-ionized water and is thus at variance with the conclusions of Rogers (unpublished) who deduced, from measurements of the admittance of a dipole probe lowered through the fluid-filled drill hole at "Byrd", that the ice surrounding the hole had a dielectric response similar to that of "pure" ice. The Antarctic ice is shown to have properties similar to those of the ice from "Camp Century" and "Site 2" in Greenland studied by Paren (1973). In an attempt to discover what factors determine the difference in electrical behaviour between polar ice and pure ice, some samples were melted and subsequently refrozen slowly. Their dielectric response was similar to that of pure polycrystalline ice. These results are discussed in connection with the impurity content and growth conditions of the ices.


Nature ◽  
2006 ◽  
Vol 442 (7104) ◽  
pp. 793-796 ◽  
Author(s):  
Hugh H. Kieffer ◽  
Philip R. Christensen ◽  
Timothy N. Titus
Keyword(s):  
Ice Cap ◽  

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