Our HST and Keck observational campaigns have detected, for the first time,escaping atmospheres around multiple young mini-Neptunes. Photoevaporation fromthese planets shapes exoplanet demographics, but one of the biggest sources ofuncertainty in modelling the outflow is the X-ray and extreme UV spectrum of thestar. Stellar EUV cannot be measured due to interstellar absorption, and mustbe inferred from the X-ray luminosity. We propose a survey to measure the X-rayspectra of four new young, active stars hosting small (<3.5 R_Earth) planets,all of which we are targeting for helium outflow observations with Keck. As abonus, XMM.s OM will measure the MUV (virgul200 nm) flux, which destroys metastablehelium and is therefore critical to modelling the helium signal we observe.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2022-09-12T19:55:15Z/2022-09-13T00:58:35Z
Version
20.08_20220509_1852
Mission Description
The European Space Agencys (ESA) X-ray Multi-Mirror Mission (XMM-Newton) was launched by an Ariane 504 on December 10th 1999. XMM-Newton is ESAs second cornerstone of the Horizon 2000 Science Programme. It carries 3 high throughput X-ray telescopes with an unprecedented effective area, and an optical monitor, the first flown on a X-ray observatory. The large collecting area and ability to make long uninterrupted exposures provide highly sensitive observations. Since Earths atmosphere blocks out all X-rays, only a telescope in space can detect and study celestial X-ray sources. The XMM-Newton mission is helping scientists to solve a number of cosmic mysteries, ranging from the enigmatic black holes to the origins of the Universe itself. Observing time on XMM-Newton is being made available to the scientific community, applying for observational periods on a competitive basis.
European Space Agency, Mr Zhaoxi Zhang, 2023, 'Photoevaporation from small planets orbiting young comma active stars openParIIclosePar', 20.08_20220509_1852, European Space Agency, https://doi.org/10.57780/esa-dqcmzi6
