Katja Poppenhaeger

The mission paper about the Next Generation Transit Survey (NGTS), a ground-based telescope network to search for transiting exoplanets, has just been published. I’m happy to be part of this project, which is a collaboration between several universities in the UK, Germany, Chile, and Switzerland – lots of exciting discoveries to come soon! Here’s some more info about the paper: We describe the Next Generation Transit Survey (NGTS), which is a ground-based project searching for transiting exoplanets orbiting bright stars….

Read More Read More

Happy to report that we have discovered three small planets, plus one additional candidate planet, around a small cool star. This is some very nice work by my PhD student Rob Wells. The planets were discovered using data from the Kepler K2 space telescope. The planets are in fairly close orbits around their host star; the candidate planet, for which we need some more data to be certain it is really a planet, might be in the habitable zone of…

Read More Read More

New paper by my PhD student Rob Wells: The detection of thousands of extrasolar planets by the transit method naturally raises the question of whether potential extrasolar observers could detect the transits of the Solar System planets. We present a comprehensive analysis of the regions in the sky from where transit events of the Solar System planets can be detected. We specify how many different Solar System planets can be observed from any given point in the sky, and find…

Read More Read More

I’m happy to be part of the Next Generation Transit Survey (NGTS) collaboration, a ground-based array of telescopes in Chile searching for exoplanets transiting their host stars. We have just published a paper on detecting false positives with NGTS, namely background transits of dim stars across brighter stars, through centroid vetting. The paper is accepted for publication by Monthly Notices of the Royal Astronomical Society. “Centroid vetting of transiting planet candidates from the Next Generation Transit Survey”, accepted by MNRAS…

Read More Read More

Happy to report that my PhD student Rachel Booth has successfully published her first paper! It’s a very interesting analysis of the magnetic activity of old cool stars, with a surprising find about the decline of activity at old stellar ages. Our paper has also been featured on the Astrobites blog: https://astrobites.org/2017/07/03/adventures-in-watchmaking-for-cool-stars/. Here’s the abstract of the paper: Stars with convective envelopes display magnetic activity, which decreases over time due to the magnetic braking of the star. This age-dependence of…

Read More Read More

Happy to report that our paper has also been picked for presentation on the Astrobites blog: https://astrobites.org/2017/03/24/a-neutron-star-in-the-eye-of-sauron/. Here’s the abstract of the paper: Fomalhaut b is a directly imaged object in the debris disk of the star Fomalhaut. It has been hypothesized to be a planet, however there are issues with the observed colours of the object that do not fit planetary models. An alternative hypothesis is that the object is a neutron star in the near fore- or background…

Read More Read More

The recent discovery of an Earth-like exoplanet around Proxima Centauri has shined a spot light on slowly rotating fully convective M-stars. When such stars rotate rapidly (period <20 days), they are known to generate very high levels of activity that is powered by a magnetic field much stronger than the solar magnetic field. Recent theoretical efforts are beginning to understand the dynamo process that generates such strong magnetic fields. However, the observational and theoretical landscape remains relatively uncharted for fully…

Read More Read More

Arcus is a NASA/MIDEX mission under development in response to the anticipated 2016 call for proposals. It is a freeflying, soft X-ray grating spectrometer with the highest-ever spectral resolution in the 8-51 Å (0.24 – 1.55 keV) energy range. The Arcus bandpass includes the most sensitive tracers of diffuse million-degree gas: spectral lines from O VII and O VIII, H- and He-like lines of C, N, Ne and Mg, and unique density- and temperature-sensitive lines from Si and Fe ions….

Read More Read More