P. P. Pedersen
A5056995340- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Adaptive optics and wavefront sensing
- Calibration and Measurement Techniques
- History and Developments in Astronomy
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Advanced Semiconductor Detectors and Materials
- Spacecraft Design and Technology
- Infrared Target Detection Methodologies
- Air Quality Monitoring and Forecasting
- Atmospheric Ozone and Climate
- CCD and CMOS Imaging Sensors
- Engineering and Test Systems
- Air Quality and Health Impacts
- COVID-19 impact on air quality
Cavendish Hospital
2020-2024
ETH Zurich
2023-2024
University of Cambridge
2020-2023
Open Geospatial Consortium
2021
One of the most promising avenues for detailed study temperate Earth-sized exoplanets is detection such planets in transit front stars small and nearby enough to make possible their thorough atmospheric characterisation with next generation telescopes like James Webb Space telescope (JWST) or Extremely Large Telescope (ELT). In this context, TRAPPIST-1 form an unique benchmark system that has gathered interest a large scientific community. The SPECULOOS survey exoplanet survey, targets...
Context. In the age of JWST, temperate terrestrial exoplanets transiting nearby late-type M dwarfs provide unique opportunities for characterising their atmospheres, as well searching biosignature gases. this context, benchmark TRAPPIST-1 planetary system has garnered interest a broad scientific community. Aims. We report here discovery and validation two super-Earths LP 890-9 (TOI-4306, SPECULOOS-2), relatively low-activity (32 pc) M6V star. The inner planet, b, was first detected by TESS...
Context . Since the discovery of first exoplanet almost three decades ago, number known exoplanets has increased dramatically. By beginning 2000s it was clear that dedicated facilities to advance our studies in this field were needed. The CHaracterising ExOPlanet Satellite (CHEOPS) is a space telescope specifically designed monitor transiting orbiting bright stars. In September 2023, CHEOPS completed its nominal mission duration 3.5 yr and remains excellent operational conditions. As...
Large sub-Neptunes are uncommon around the coolest stars in Galaxy and rarer still those that metal-poor. However, owing to large planet-to-star radius ratio, these planets highly suitable for atmospheric study via transmission spectroscopy infrared, such as with JWST. Here we report discovery validation of a sub-Neptune orbiting thick-disk, mid-M dwarf star TOI-2406. We first infer properties host by analysing star's near-infrared spectrum, spectral energy distribution, Gaia parallax. use...
ABSTRACT SPECULOOS-South, an observatory composed of four independent 1-m robotic telescopes, located at ESO Paranal, Chile, started scientific operation in 2019 January. This Southern hemisphere facility operates as part the Search for Habitable Planets EClipsing ULtra-cOOl Stars (SPECULOOS), international network 1-m-class telescopes surveying transiting terrestrial planets around nearest and brightest ultracool dwarfs (UCDs). To automatically efficiently process observations to deal with...
SPECULOOS is a ground-based transit survey consisting of six identical 1-m robotic telescopes. The immediate goal the project to detect temperate terrestrial planets transiting nearby ultracool dwarfs (late M-dwarf stars and brown dwarfs), which could be amenable for atmospheric research with next generation Here, we report developments northern counterpart - Northern Observatory, present its performance during first three years operations from mid-2019 mid-2022. Currently, observatory...
In the last decade, a dozen close-in giant planets have been discovered orbiting stars with spectral types ranging from M0 to M4, mystery since known formation pathways do not predict existence of such systems. Here, we confirm TOI-4860 b, Jupiter-sized planet an M4.5 host, star at transition between fully and partially convective interiors. First identified TESS data, validate transiting companion's planetary nature through multicolour photometry TRAPPIST-South/North, SPECULOOS, MuSCAT3...
A new generation of observatories is enabling detailed study exoplanetary atmospheres and the diversity alien climates, allowing us to seek evidence for extraterrestrial biological geological processes. Now therefore time identify most unique planets be characterised with these instruments. In this context, we report on discovery validation TOI-715 b, a $R_{\rm b}=1.55\pm 0.06\rm R_{\oplus}$ planet orbiting its nearby ($42$ pc) M4 host (TOI-715/TIC 271971130) period $P_{\rm b} =...
ABSTRACT We report the discovery of a brown dwarf orbiting M1 host star. first identified within Next Generation Transit Survey data, with supporting observations found in TESS sectors 11 and 38. confirmed follow-up photometry from South African Astronomical Observatory, SPECULOOS-S, TRAPPIST-S, radial velocity measurements HARPS, which allowed us to characterize system. find an orbital period ∼1.25 d, mass $69.0^{+5.3}_{-4.8}$ MJ, close hydrogen burning limit, radius 0.95 ± 0.05 RJ....
Abstract We present the discovery of TOI 762 A b and TIC 46432937 b, two giant planets transiting M-dwarf stars. Transits both systems were first detected from observations by NASA TESS mission, objects are confirmed as through high-precision radial velocity carried out with Very Large Telescope/ESPRESSO. is a warm sub-Saturn mass 0.251 ± 0.042 M J , radius 0.744 0.017 R an orbital period 3.4717 days. It transits mid-M-dwarf star 0.442 0.025 ☉ 0.4250 0.0091 . The has resolved binary...
New sets of young M dwarfs with complex, sharp-peaked, and strictly periodic photometric modulations have recently been discovered Kepler/K2 (scallop shells) TESS (complex rotators). All are part star-forming associations, distinct from other variable stars, likely belong to a unified class. Suggested hypotheses include star spots, accreting dust disks, co-rotating clouds material, magnetically constrained spots misaligned pulsations. Here, we provide comprehensive overview add new...
ABSTRACT HIP 41378 f is a temperate 9.2 ± 0.1 R⊕ planet with period of 542.08 d and an extremely low density 0.09 0.02 g cm−3. It transits the bright star (V = 8.93), making it exciting target for atmospheric characterization including transmission spectroscopy. was monitored photometrically between dates 2019 November 19 28. We detected transit NGTS, just third ever this planet, which confirms orbital period. This also first ground-based detection f. Additional photometry obtained used to...
Abstract The temporary decrease of fine particulate matter (PM 2.5 ) concentrations in many parts the world due to COVID-19 lockdown spurred discussions on urban air pollution and health. However there has been little focus sub-Saharan Africa, as few African cities have quality monitors if they do, these data are often not publicly available. Spatial differentials changes PM a result COVID also remain largely unstudied. To address this gap, we use serendipitous mobile monitoring deployment...
ABSTRACT We present the discovery and characterization of an eclipsing binary identified by Next Generation Transit Survey in ∼115-Myr-old Blanco 1 open cluster. NGTS J0002−29 comprises three M dwarfs: a short-period companion wider orbit. This system is first well-characterized, low-mass 1. With low mass ratio, tertiary companion, components that straddle fully convective boundary, it important benchmark system, one only two binaries at this age. simultaneously model light curves from NGTS,...
We present the photometric performance of SPIRIT, a ground-based near-infrared InGaAs CMOS-based instrument (1280 by 1024 pixels, 12 micron pitch), using on-sky results from SPECULOOS-Southern Observatory during 2022 - 2023. SPIRIT was specifically designed to optimise time-series precision for observing late M and L type stars. To achieve this, custom wide-pass filter (0.81 1.33 microns, zYJ ) used, which also minimise effects atmospheric precipitable water vapour (PWV) variability on...
We report on the discovery of a transiting Earth-sized (0.95$R_\oplus$) planet around an M3.5 dwarf star at 57$\,$pc, K2-315b. The has period $\sim$3.14 days, i.e. ${\sim}\pi$, with instellation 7.45$\,$S$_{\oplus}$. detection was made using publicly available data from $\textit{K2}$'s Campaign 15. observed three additional transits SPECULOOS Southern and Northern Observatories, stellar spectrum Keck/HIRES, which allowed us to validate planetary nature signal. confirmed is well suited for...
SPECULOOS (Search for habitable Planets EClipsing ULtra-cOOl Stars) aims to perform a transit search on the nearest ($<40$pc) ultracool ($<3000$K) dwarf stars. The project's main motivation is discover potentially planets well-suited detailed atmospheric characterisation with upcoming giant telescopes, like James Webb Space Telescope (JWST) and European Large (ELT). project based network of 1m robotic namely four ones SPECULOOS-Southern Observatory (SSO) in Cerro Paranal, Chile, one...
The variability induced by precipitable water vapour (PWV) can heavily affect the accuracy of time-series photometric measurements gathered from ground, especially in near-infrared. We present here a novel method modelling and mitigating this variability, as well open-sourcing developed tool -- Umbrella. In study, we evaluate extent to which photometry three common bandpasses (r', i', z'), SPECULOOS' primary bandpass (I+z'), are photometrically affected PWV variability. selection bandpasses,...
We report the discovery of a brown dwarf orbiting M1 host star. first identified within Next Generation Transit Survey data, with supporting observations found in TESS sectors 11 and 38. confirmed follow-up photometry from South African Astronomical Observatory, SPECULOOS-S, TRAPPIST-S, radial velocity measurements HARPS, which allowed us to characterise system. find an orbital period ~1.25 d, mass 69.0+5.3-4.8 MJ, close Hydrogen burning limit, radius 0.95 +- 0.05 RJ. determine age be >0.5...
The SPECULOOS (Search for habitable Planets EClipsing ULtra-cOOl Stars) project aims to detect temperate terrestrial planets transiting nearby ultracool dwarfs, including late M-dwarf stars and brown which are well-suited atmospheric characterization using the James Webb Space Telescope (JWST) upcoming giant telescopes like European Extremely Large (ELT). Led by University of Liège, is conducted in partnership with Cambridge, Birmingham, Massachusetts Institute Technology, Bern, ETH Zurich....
Context. Small planets transiting bright nearby stars are essential to our understanding of the formation and evolution exoplanetary systems. However, few constitute prime targets for atmospheric characterization, even fewer part multiple star Aims. This work aims validate TOI-4336 A b, a sub-Neptune-sized exoplanet candidate identified by TESS space-based transit survey around M dwarf. Methods. We validated planetary nature b through global analysis follow-up multi-band high-precision...
We present the discovery of TOI 762 A b and TIC 46432937 b, two giant planets transiting M dwarf stars. Transits both systems were first detected from observations by NASA TESS mission, objects are confirmed as through high-precision radial velocity (RV) carried out with VLT/ESPRESSO. is a warm sub-Saturn mass 0.251 +- 0.042 M_J, radius 0.744 0.017 R_J, an orbital period 3.4717 d. It transits mid-M star 0.442 0.025 M_S 0.4250 0.0091 R_S. The has resolved binary companion B that separated...