Evidence for a rapid decrease in Pluto's atmospheric pressure revealed by a stellar occultation in 2019

We report observations of a stellar occultation by Pluto on 2019 July 17. A single-chord high-speed (time resolution $= 2\,$s) photometry dataset was obtained with a CMOS camera mounted on the Tohoku University 60 cm telescope (Haleakala, Hawaii). The occultation light curve is satisfactorily fitted to an existing Pluto's atmospheric model. We find the lowest pressure value at a reference radius of $r = 1215~{\rm km}$ among those reported after 2012, indicating a possible rapid (approximately $21^{+4}_{-5} \%$ of the previous value) pressure drop between 2016 (the latest reported estimate) and 2019. However, this drop is detected at a $2.4\sigma$ level only and still requires confirmation from future observations. If real, this trend is opposite to the monotonic increase of Pluto's atmospheric pressure reported by previous studies. The observed decrease trend is possibly caused by ongoing ${\rm N_2}$ condensation processes in the Sputnik Planitia glacier associated with an orbitally driven decline of solar insolation, as predicted by previous theoretical models. However, the observed amplitude of the pressure decrease is larger than the model predictions.Comment: 7 pages, 3 figures, accepted for publication in Astronomy and Astrophysic

Green outdoor places, stress and productivity: an exploratory study at Kista ICT Hub, Stockholm, Sweden

In modern world a workplace can be defined as a location where someone works for his or her employer, a place of employment. In technology industry such locations got a name - tech hub. A tech hub is a specific area or a part of a city with a specific building or set of buildings where companies can rent space alongside each other to share facilities and ideas. Kista ICT Hub is one of the most important places for jobs in Stockholm and in the region. ICT related professionals are at a constant pressure to deliver services efficiently and have to be cost effective. Hence, stress is high in ICT professions because of their nature of work. The aim of this study is to explore how physical and/or visual access to green outdoor environments at a tech hub, might relate to employees’ stress level and productivity loss. Data about the perceived physical and/or visual access to greenery, perceived stress level and loss of productivity of employees were collected by means of questionnaire, qualitative interviews and observation. The principle of triangulation has been the main approach. Obtained quantitative data indicate that reported perceived level of stress might increase with the presence of green outdoor environments. Whereas productivity loss (fewer missing days due to personal illnesses) seems to improve when physical access/or view of greenery is perceived in the environment. Qualitative data and observation suggest that the lack of greenery at workplace and location of green outdoor places might be compensated by efficient office planning, comfortable interior design, presence of indoor plants and dedicated place for rest and relaxation. Lastly, a discrepancy has been identified between the perception of physical access to greenery and reality