Ice shelves line the peripheries of Antarctica. Rift and crevasses are two main deformational structures affecting ice shelf stability. The present study deals with propagation-widening of five active rifts and future potential calving zones on Amery Ice Shelf (AIS), East Antarctica, between 2000 and 2017 using moderate resolution image spectroradiometer (MODIS) data. The widening and rift propagating rate, as well as advancement in AIS show abnormal behaviour. The expansion of AIS differs across the shelf. The highest rate of advancement was observed in 2012-2013 (~517 sq. km) and the lowest was observed in 2000-2001 (~35 sq. km). The rift system shows variability in its proportion and having poor relationship with environmental processes, which suggests heterogeneities in the AIS. The abnormal behaviour of rift propagation during the study period can be attributed to tsunamis, tide, current action, crevasses pattern and icequakes in the vicinity of the study region.

Spectral reflectance data derived from Moon Mineralogy Mapper (M 3) onboard India's Chandrayaan-1 has revealed Fe bearing Mg-spinel-rich lithology on central peaks of the crater Theophilus. These newly identified Fe bearing Mg-spinel-rich rock types are defined by their strong 2-μm absorption and lack of 1-μm absorptions in spectral reflectance response. Such lithology has been reported previously along the inner ring of Moscoviense Basin on the lunar far side. The Modified Gaussian Modeling (MGM) analysis of the Fe bearing Mg-spinel reflectance spectra has been done and the results of the analysis clearly bring out a strong spectral absorption at 1872 nm with no significant absortion around 1000 nm. The presence of spinel group of minerals in the Theophilus central peak and the fact that central peaks mostly represent uplifted mass of deep crustal material confirm that central peaks can be used as a window to study the deep crustal and/or upper mantle composition and may lead to a fresh perspective about the crustal composition of Moon.

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The areal extent of many Himalayan glaciers is decreasing where number of glaciers is increasing. This increasing number is subject to the fragmentation of limbs of main trunk glacier. However, disintegration of limbs is not observed in all the glacier system. This paper emphases the scenario of the fragmentation occurred in glaciers. Two glaciers from the two different basins have been taken into the consideration for this study. The peculiar characteristic of these glaciers is that, the tributary glaciers are showing less retreat in compare to main trunk glaciers. Due to this reason the rate of shift in snout is higher in main trunk glaciers than tributary glaciers. However, in recent data the tributary glaciers have experienced little higher loss in glacial ice than main glacier. But the shift of snout in main trunk glacier is no doubt surprising since past. Therefore, various parameters have been examined to identify the cause of such a behavior of glaciers. The common factors observed in both the glaciers are accumulation area ratio which is higher, snow line altitude which is lower in tributary glaciers for the period of 2005-2013. Another factor is the orientation as tributary glaciers are towards NE direction. In addition, slope of Dharlang glacier (main limb) is 4˚ where it is 18˚ in tributary glacier.