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A daily view of all the goings-on at ASTRON and JIVE.
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    © Roy van der Werp

    Friday 12th October marked the first day of the APERTIF shakedown, an operations test designed to help us assess how the overall system is doing and how close we are to our aimed-for model of operations. For 11 days straight, there will be a mix of interferometric and ARTS observations, as well as calibrations, in an action-packed schedule. We'll be making use of both the APERTIF Task DataBase (ATDB) and the APERTIF Long Term Archive (ALTA) to manage and ingest all observations carried out. For the APERTIF imaging surveys, the goal will be to test the current reduction pipeline, assess data quality, and determine the effectiveness of survey observing and calibration strategy. For ARTS, observations will be conducted for science cases involving timing pulsars and finding new FRBs. These observations will test the system stability and sensitivity over long duration observations as well as the real-time transient search pipeline AMBER. The lead-up to this first APERTIF shakedown has been a culmination of a lot of effort and hard work by many people, only some of which are pictured in this photo. We are looking forward to a busy 11 days, as well as many lessons learned to help us improve APERTIF for the fast-approaching start of 2019!

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    © MingChuan Wei, Harbin Institute of Technology

    This image shows our own planet Earth, as well as the far side of the Moon. The image was taken with a camera linked to an amateur radio transceiver onboard the Chinese Longjiang-2 satellite, currently in orbit around the Moon, and transmitted back to Earth where it was received with the Dwingeloo telescope.

    This image represents the culmination of several observing sessions spread over the past few months where we used the Dwingeloo telescope in collaboration with the Chinese team from Harbin University of Technology, who built the radio transceiver onboard Longjiang-2, and radio amateurs spread across the globe. During these sessions we tested receiving telemetry through low-bit rate and error-resistant digitally modulated GMSK transmissions, as well as the JT4G modulation scheme designed by Nobel prize winning astrophysicist Joe Taylor for weak signal Moonbounce experiments. Besides telemetry, we performed a VLBI experiment by simultaneously observing Longjiang-2 from China and Dwingeloo, and also downloaded images taken by Longjiang-2 of the lunar surface, lens flares, and the starry sky as seen from lunar orbit.

    The transceiver onboard Longjiang-2 was designed to allow radio amateurs to downlink telemetry and relay messages through a satellite in lunar orbit, as well as command it to take and downlink images. In that it has succeeded, as many radio amateurs have received telemetry and image data. Being able to use the Dwingeloo telescope to help with this has been a lot of fun.


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    © nl-RSE

    Earlier this year, the initiative was taken to organise the Dutch Research Software Engineer (RSE) community, inspired by the British and German RSE initiative. On 20 september, the first meetup was organised in Utrecht at the Jaarbeurs Innovation Mile.

    The concept of RSE is broadly defined as any person writing software to be used in science, including but not limited to PhDs and postdocs writing software packages, software developers at universities, and independent developers working in the academic field. The goal of the meetup was bring together members of the Duth RSE community and identify what topics are important and of common interest to the Dutch RSE field.

    The full ASTRON Science Data Group (both members! Try to find them in the picture) was present at the meeting. The keynote speech was given by one of the initiators of the UK-RSE movement, Ilian Todorov. The rest of the meeting consisted of discussions about what the Dutch RSE community should focus on.

    We look forward to what this movement could achieve in improving the quality and recognition of software in the Dutch academic community. If you want to keep posted on this topic, consider joining the mailing list here.


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    © Colloquium

    Cosmic-ray bombardment initiates the production of a number of different isotopes in the atmosphere, particularly 14C (or radiocarbon). The activity of 14C in the atmosphere has varied over time due to modulation of the incident cosmic flux by heliomagnetic and geomagnetic effects, and the release of 14C-depleted carbon into the environmental by climatic effects and volcanism. The past record of 14C in the atmosphere is preserved in natural tree-ring archives. Such time-series show that year-to-year variation has usually been around 1-2%.

    In 2012, a Japanese team measuring 14C measurements on known-age tree-rings discovered a sudden jump in activity (~12�) between 774 and 775 CE. Soon after, the same pattern was found in tree-rings from Russia, Germany, US and New Zealand, proving the uplift was both global and synchronous. No known terrestrial environmental process could have caused such rapid and simultaneous enrichment. Hence it was quickly realised the cause must have been a major burst of radiation from space. Moreover, estimations of the energy of the event suggested it was too intense to be attributed to solar activity. Galactic supernovae, gamma-ray bursts, cometary impacts and solar superflares have all since been posited as the cause. A key factor in understanding the events has been the discovery of three more rapid increases in 14C activity: in 993 and 1218 CE, and 3372 BCE. This seminar will cover the ongoing debate around the astrophysical origin of these events, as well as touching on their wide-ranging implications.


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  • 10/18/18--17:00: Christiaan Huygens prijs
  • © ASTRON

    The Christiaan Huygens prijs is awarded annually for an outstanding Dutch PhD thesis. Each year the prize is granted in one of the fields of study in which Christiaan Huygens made a sizeable contribution.

    This year the prize was awarded to Adrian Hamers, who completed his thesis "Hierarchical Systems" at Leiden University. Adrian's thesis presents a generalised approach to modelling the gravitational interactions of many-body systems in which there is a hierarchy of distinct size scales. Honourable mentions were awarded to Tjalling de Haas (Utrecht) and Nienke van der Marel (Leiden).

    The jury consisted of members from the Royal Dutch Academy of Sciences (KNAW) and De Jonge Akademie: Amina Helmi (Groningen), Henny Lamers (Amsterdam) and Jason Hessels (ASTRON/Amsterdam). The ceremony took place at the Oudekerk in Voorburg, only a stone's throw away from where Huygens lived and worked.

    It was stunning to see the research talent that exists in the Netherlands, and a joy to celebrate both science and the achievements of young Dutch researchers.