Our team has discovered the first ultra-hot Neptune\: LTT 9779b. This exoplanetis located just 0.017 au from its G7V host star, in the middle of the so-calledNeptunian desert, and its survival under presumably intense X-ray irradiation isa mystery. All previous evidence points to close-in Neptunes being stripped oftheir gaseous envelopes and being reduced to hot rocky cores. We propose toobserve the host star with XMM-Newton in order to determine the present X-rayirradiation. If the star is found to have normal coronal activity, we will beforced to consider novel evolutionary scenarios for this system.
Instrument
EMOS1, EMOS2, EPN, OM, RGS1, RGS2
Temporal Coverage
2021-05-27T18:30:27Z/2021-05-28T09:15:27Z
Version
19.16_20210326_1200
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, Prof Peter Wheatley, 2022, 'The mysterious survival of volatiles on the first ultra-hot Neptune', 19.16_20210326_1200, European Space Agency, https://doi.org/10.57780/esa-mrf0g67
