Final report on project SP1210: Lowland peatland systems in England and Wales – evaluating greenhouse gas fluxes and carbon balances

Lowland peatlands represent one of the most carbon-rich ecosystems in the UK. As a result of widespread habitat modification and drainage to support agriculture and peat extraction, they have been converted from natural carbon sinks into major carbon sources, and are now amongst the largest sources of greenhouse gas (GHG) emissions from the UK land-use sector. Despite this, they have previously received relatively little policy attention, and measures to reduce GHG emissions either through re-wetting and restoration or improved management of agricultural land remain at a relatively early stage. In part, this has stemmed from a lack of reliable measurements on the carbon and GHG balance of UK lowland peatlands. This project aimed to address this evidence gap via an unprecedented programme of consistent, multi year field measurements at a total of 15 lowland peatland sites in England and Wales, ranging from conservation managed ‘near-natural’ ecosystems to intensively managed agricultural and extraction sites. The use of standardised measurement and data analysis protocols allowed the magnitude of GHG emissions and removals by peatlands to be quantified across this heterogeneous data set, and for controlling factors to be identified. The network of seven flux towers established during the project is believed to be unique on peatlands globally, and has provided new insights into the processes the control GHG fluxes in lowland peatlands. The work undertaken is intended to support the future development and implementation of agricultural management and restoration measures aimed at reducing the contribution of these important ecosystems to UK GHG emissions

Dynamically Controlling Image Integration Onboard the Star-Planet Activity Research CubeSat (SPARCS)

The Star-Planet Activity Research CubeSat (SPARCS) is a 6U CubeSat astronomical observatory underdevelopment and will be entirely dedicated to the photometric monitoring of the flaring activity of M dwarfs at near-UV (258 nm – 308 nm) and far-UV (153 nm–171 nm) wavelengths. The SPARCS science pay load is composed of a 9-cm telescope that projects a 40’ field-of-view onto two UV-optimized delta-doped charge-coupled devices (CCDs), which are controlled by a dedicated payload processor board. Given that M dwarf flares in the UV are expected to be capable of reaching amplitudes ∼14,000 times above their quiescent flux, with durations that can be as short as a couple of minutes, the SPARCS payload processor is designed to be able to dynamically adjust the imaging system’s integration times and gains on the fly to reduce CCD pixel saturation issues when flaring events are detected. The SPARCS payload processor is a BeagleBone Black (BBB) with a protective Pumpkin Motherboard Module 2, and runs a custom fully Python-based software to perform active detector thermal control, manage science observations, and apply near-real time image processing to autonomously adjust the exposure times and gains of the detectors upon flare detection. Here we present the approach adopted for that automated dynamic exposure control, as well as its pre-flight tests and performance using simulated M dwarf light curves and full-frame images in the two SPARCS passbands

Deep Hubble Space Telescope observations of star clusters in NGC 1275

We present an analysis of compact star clusters in deep Hubble Space Telescope Wide Field Planetary Camera 2 images of NGC 1275. B- and R-band photometry of roughly 3000 clusters shows a bimodality in the B-R colors, suggesting that distinct old and young cluster populations are present. The small spread in the colors of the blue clusters is consistent with the hypothesis that they are a single-age population, with an inferred age of 0.1 to 1 Gyr. The luminosity function shows increasing numbers of blue clusters to the limit of our photometry, which reaches several magnitudes past the turnover predicted if the cluster population is identical to current Galactic globular clusters seen at a younger age. The blue clusters have a spatial distribution that is more centrally peaked than that of the red clusters. The individual clusters are slightly resolved, with core radii ≾0.75 pc if they have modified Hubble profiles. We estimate the specific frequencies of the old and young populations and discuss the uncertainties in these estimates. We find that the specific frequency of the young population in NGC 1275 is currently larger than that of the old population and will remain so as the young population evolves, even if the majority of the low-mass clusters are eventually destroyed. If the young population formed during a previous merger, this suggests that mergers can increase the specific frequency of globular clusters in a galaxy. However, the presently observed young population likely contains too few clusters to have a significant impact on the overall specific frequency as it will be observed in the future