Tranquility Science Duty Logs

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Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230210.0305

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230210.0300
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Brightened with 0.05 magnitude.

Today's project : Stable lifetime of compact, evenly-spaced planetary systems with non-equal masses.

Compact planetary systems with more than two planets can undergo orbital crossings from planet-planet perturbations. The time which the system remains stable without orbital crossings has an exponential dependence on the initial orbital separations in units of mutual Hill radii. However when a multi-planet system has period ratios near mean-motion resonances, its stability time differs from the time determined by planet separation. This difference can be up to an order of magnitude when systems are set up with chains of equal period ratios. We use numerical simulations to describe the stability time relationship in non-resonant systems with equal separations but non-equal masses which breaks the chains of equal period ratios. We find a deviation of 30 per cent in the masses of Earth-mass planets creates a large enough deviation in the period ratios where the average stability time of a given spacing can be predicted by the stability time relationship. The mass deviation where structure from equal period ratios is erased increases with planet mass but does not depend on planet multiplicity. With a large enough mass deviation, the distribution of stability time at a given spacing is much wider than in equal-mass systems where the distribution narrows due to period commensurabilities. We find the stability time distribution is heteroscedastic with spacing—the deviation in stability time for a given spacing increases with said spacing.

-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230213.0526

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230213.0500
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Brightened with 0.11 magnitude.

Today's project : TOI-561 b: A Low-density Ultra-short-period "Rocky" Planet around a Metal-poor Star.

TOI-561 is a galactic thick-disk star hosting an ultra-short-period (0.45-day-orbit) planet with a radius of 1.37 R⊕, making it one of the most metal-poor ([Fe/H] = −0.41) and oldest (≈10 Gyr) sites where an Earth-sized planet has been found. We present new simultaneous radial velocity (RV) measurements from Gemini-N/MAROON-X and Keck/HIRES, which we combined with literature RVs to derive a mass of Mb = 2.24 ± 0.20 M⊕. We also used two new sectors of TESS photometry to improve the radius determination, finding Rb = 1.37 ± 0.04 R⊕ and confirming that TOI-561 b is one of the lowest-density super-Earths measured to date (ρb = 4.8 ± 0.5 g cm−3). This density is consistent with an iron-poor rocky composition reflective of the host star's iron and rock-building element abundances; however, it is also consistent with a low-density planet with a volatile envelope. The equilibrium temperature of the planet (∼2300 K) suggests that this envelope would likely be composed of high mean molecular weight species, such as water vapor, carbon dioxide, or silicate vapor, and is likely not primordial. We also demonstrate that the composition determination is sensitive to the choice of stellar parameters and that further measurements are needed to determine whether TOI-561 b is a bare rocky planet, a rocky planet with an optically thin atmosphere, or a rare example of a nonprimordial envelope on a planet with a radius smaller than 1.5 R⊕.

-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230214.0229

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230214.0200
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Daystar condition = Thermal radiation within acceptable margins. One sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Brightened with 0.02 magnitude.

Today's project : Updated characterization of long-period single companion by combining radial velocity, relative astrometry, and absolute astrometry.

Context. Thanks to more than 20 yr of monitoring, the radial velocity (RV) method has detected long-period companions (P > 10 yr) around several dozens of stars. Yet, the true nature of these companions remains unclear because of the uncertainty as to the inclination of the companion orbital plane.

Aims. We wish to constrain the orbital inclination and the true mass of long-period single companions.

Methods. We used a Markov chain Monte Carlo (MCMC) fitting algorithm to combine RV measurements with absolute astrometry and, when available, relative astrometry data.

Results. We have lifted the sin(i) indetermination for seven long-period companions. We find true masses in the planetary mass range for the candidate planets detected in the following systems: Epsilon Indi A, HD 13931, HD 115954, and HD 222155. The mass of HD 219077 b is close to the deuterium-burning limit and its nature is uncertain because of the imprecise mass of the host star. Using additional RV measurements, we refine the orbital parameters of HIP 70849 b and find a mass in the planetary range. By combining RV data with absolute and relative astrometry, we significantly improve the characterization of HD 211847 B and properly determine its mass, which appears to be in the low-mass star range. This work illustrates how Gaia and HIPPARCOS allow for the orbital properties and masses of long-period RV companions to be further constrained.

-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230216.0004

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230216.0001
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report.

We have the pleasure to communicate that the "old" Mk IV-ultra-long-range beacons are replaced by enhanced Mk-VII beacons. Therefore it's possible again to bring the weather report back to Tranquility in order to provide important forecasts for Pinastri. We expect to be ready in a couple of days after extensive testing.

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. No change in magnitude the last 24 hrs.

Today's project : Correcting Exoplanet Transmission Spectra for Stellar Activity with an Optimised Retrieval Framework.

Stellar activity in the form of photospheric heterogeneities such as spots and faculae may present a significant noise source for exoplanetary observations by introducing a chromatic contamination effect to the observed transmission spectrum. If this contamination is not identified and corrected for, it can introduce substantial bias in our analysis of the planetary atmosphere. In this work we aim to determine how physically realistic and complex our stellar models must be in order to accurately extract the planetary parameters from transmission spectra. We explore which simplifying assumptions about the host star are valid at first order and examine if these assumptions break down in cases of extreme stellar activity. To do this, we use a more complex stellar model (StARPA) as the input observation for a combined stellar-planetary retrieval with TauREx3, in which the contamination is accounted for using a simplified stellar model (ASteRA). Using the StARPA model as a benchmark, we validate the use of ASteRA using a retrieval framework of 27 simulated, spot-contaminated transmission spectra to determine in which conditions it performs most favourably. For cases of low to moderate stellar activity ASteRA performs well, retrieving the planetary parameters with a high degree of accuracy. For the most active cases some residual contamination remains due to ASteRA neglecting the effect of limb darkening. Nevertheless, using ASteRA presents a substantial improvement over neglecting the contamination entirely, which can result in retrieved planetary parameters that are incorrect by up to two orders of magnitude.

-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230217.0738

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230217.0600
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report.

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. No change in magnitude the last 48 hrs.

Today's project : AF Lep b: the lowest mass planet detected coupling astrometric and direct imaging data

Aims. Using the direct imaging technique we searched for low mass companions around the star AF Lep that presents a significant proper motion anomaly (PMa) signal obtained from the comparison of Hipparcos and Gaia eDR3 catalogs. Methods. We observed AF Lep in two epochs with VLT/SPHERE using its subsystems IFS and IRDIS in the near-infrared (NIR) covering wavelengths ranging from the Y to the K spectral bands (between 0.95 and 2.3 {\mu}m). The data were then reduced using the high-contrast imaging techniques angular differential imaging (ADI) and spectral differential imaging (SDI) to be able to retrieve the signal from low mass companions of the star. Results. A faint companion was retrieved at a separation of ~0.335" from the star and with a position angle of ~70.5 deg in the first epoch and with a similar position in the second epoch. This corresponds to a projected separation of ~9 au. The extracted photometry allowed us to estimate for the companion a mass between 2 and 5 MJup. This mass is in good agreement with what is expected for the dynamic mass of the companion deduced using astrometric measures (5.2-5.5 MJup). This is the first companion with a mass well below the deuterium burning limit discovered coupling direct imaging with PMa measures. Orbit fitting done using the orvara tool allowed to further confirm the companion mass and to define its main orbital parameters.

-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230220.0042

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230220.0030
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Surface environmental conditions

Nitrogen = 77.4 percent
Oxygen = 21.3 percent
Argon = 0.88 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.26 percent
Water vapor = 0 - 4 percent

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-groupings detected with rather minor flares. Minimal elevated interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Dimmed with 0.13 magnitude.

Today's project : Direct imaging discovery of a super-Jovian around the young Sun-like star AF Leporis.

Expanding the sample of directly imaged companions to nearby, young stars that are amenable to detailed astrometric and spectroscopic studies is critical for the continued development and validation of theories of their evolution and atmospheric processes. The recent release of the {\it Gaia} astrometric catalogue allows us to efficiently search for these elusive companions by targeting those stars that exhibit the astrometric reflex motion induced by an orbiting companion. The nearby (27 pc), young (24 Myr) star AF Leporis (AF Lep) was targeted because of its astrometric acceleration, consistent with a wide-orbit planetary companion detectable with high-contrast imaging.
We used the SPHERE instrument on the UFST (UFS Telescope) to search for faint substellar companions in the immediate vicinity of AF Lep. We used observations of a nearby star interleaved with those of AF Lep to efficiently subtract the residual point spread function. This provided sensitivity to faint planetary-mass companions within 1 arcsec (∼30 au) of the star. We detected the companion AF Lep b at a separation of 339 mas (9 au), within the inner edge of its unresolved debris disk. The measured K-band contrast and the age of the star yield a model-dependent mass of 4--6 MJup, consistent with the mass derived from an orbital fit of 4.3+2.9−1.2 MJup. The near-infrared SED of the planet is consistent with an object at the L--T transition, but under-luminous with respect to field-gravity objects.
AF Lep b joins a growing number of substellar companions imaged around stars in the young β Pic moving group. With a mass of between 3--7 MJup, it occupies a gap in this isochronal sequence between the hotter, more massive companions like PZ~Tel~B and β~Pic~b, and the cooler 51~Eri~b which is sufficiently cool for the formation of methane within its photosphere.


-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230221.0037

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230221.0035
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Surface environmental conditions

Nitrogen = 77.3 percent
Oxygen = 21.4 percent
Argon = 0.88 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.22 percent
Water vapor = 0 - 4 percent

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-groupings detected with rather minor flares. Minimal elevated interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Dimmed with 0.11 magnitude.

Today's project : ExoClock Project. III. 450 New Exoplanet Ephemerides from Ground and Space Observations.

The ExoClock project has been created to increase the efficiency of the Ariel mission. It will achieve this by continuously monitoring and updating the ephemerides of Ariel candidates, in order to produce a consistent catalog of reliable and precise ephemerides. This work presents a homogenous catalog of updated ephemerides for 450 planets, generated by the integration of ∼18,000 data points from multiple sources. These sources include observations from ground-based telescopes (the ExoClock network and the Exoplanet Transit Database), midtime values from the literature, and light curves from space telescopes (Kepler, K2, and TESS). With all the above, we manage to collect observations for half of the postdiscovery years (median), with data that have a median uncertainty less than 1 minute. In comparison with the literature, the ephemerides generated by the project are more precise and less biased. More than 40% of the initial literature ephemerides had to be updated to reach the goals of the project, as they were either of low precision or drifting. Moreover, the integrated approach of the project enables both the monitoring of the majority of the Ariel candidates (95%), and also the identification of missing data. These results highlight the need for continuous monitoring to increase the observing coverage of the candidate planets. Finally, the extended observing coverage of planets allows us to detect trends (transit-timing variations) for a sample of 19 planets. All the products, data, and codes used in this work are open and accessible to the wider scientific community.


-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230222.0114

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230222.0105
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Surface environmental conditions

Nitrogen = 77.4 percent
Oxygen = 21.3 percent
Argon = 0.87 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.23 percent
Water vapor = 0 - 4 percent

Daystar condition = Thermal radiation within acceptable margins. Three sunspot-groupings detected with rather minor flares. Minimal elevated interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Dimmed with 0.02 magnitude.

Today's project : Resonant Interaction of Energetic Electrons with Radio Emission in the Magnetospheres of Exoplanets.

We analyze the resonant interaction of energetic electrons with radio emission in the magnetospheres of exoplanets using the planet Tau Bootis b as an example. The conditions of this interaction and its impact on the parameters of electrons are considered for the radio emission which is detectable on the Earth. Specific features of the interaction are studied in comparison with the interaction of energetic electrons with auroral kilometric radiation in the Earth’s magnetosphere. It is shown that for the considered parameters of the magnetosphere of Tau Bootis b and radio emission in it, the resonant interaction of electrons with radio emission is strongly nonlinear. For a wave packet of finite duration, the interaction can cause a significant acceleration of particles in a wide range of energies (from tens to hundreds of kiloelectronvolts).


-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230223.0156

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230223.0153
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Surface environmental conditions

Nitrogen = 77.3 percent
Oxygen = 21.4 percent
Argon = 0.87 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.22 percent
Water vapor = 0 - 4 percent

Daystar condition = Thermal radiation within acceptable margins. Three sunspot-groupings detected with rather minor flares. Minimal elevated interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Dimmed with 0.06 magnitude.

Today's project : TOI-3984 A b and TOI-5293 A b: two temperate gas giants transiting mid-M dwarfs in wide binary systems.

We confirm the planetary nature of two gas giants discovered by TESS to transit M dwarfs with stellar companions at wide separations. TOI-3984 A (J=11.93) is an M4 dwarf hosting a short-period (4.353326±0.000005 days) gas giant (Mp=0.14±0.03 MJ and Rp=0.71±0.02 RJ) with a wide separation white dwarf companion. TOI-5293 A (J=12.47) is an M3 dwarf hosting a short-period (2.930289±0.000004 days) gas giant (Mp=0.54±0.07 MJ and Rp=1.06±0.04 RJ) with a wide separation M dwarf companion. We characterize both systems using a combination of ground-based and space-based photometry, speckle imaging, and high-precision radial velocities from the Habitable-zone Planet Finder and NEID spectrographs. TOI-3984 A b (Teq=563±15 K and TSM=138+29−27) and TOI-5293 A b (Teq=675+42−30 K and TSM=92±14) are two of the coolest gas giants among the population of hot Jupiter-sized gas planets orbiting M dwarfs and are favorable targets for atmospheric characterization of temperate gas giants and three-dimensional obliquity measurements to probe system architecture and migration scenarios.


-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230227.0435

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230227.0430
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Surface environmental conditions

Nitrogen = 77.1 percent
Oxygen = 21.1 percent
Argon = 0.87 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.25 percent
Water vapor = 0 - 4 percent

Daystar condition = Thermal radiation within acceptable margins. Three sunspot-groupings detected with rather minor flares. Minimal elevated interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Dimmed with 0.01 magnitude.

Today's project : CRIRES+ detection of CO emissions lines and temperature inversions on the dayside of WASP-18b and WASP-76b

The dayside atmospheres of ultra-hot Jupiters (UHJs) are predicted to possess temperature inversion layers with extremely high temperatures at high altitudes. We observed the dayside thermal emission spectra of WASP-18b and WASP-76b with the new CRIRES+ high-resolution spectrograph at near-infrared wavelengths. Using the cross-correlation technique, we detected strong CO emission lines in both planets, which confirms the existence of temperature inversions on their dayside hemispheres. The two planets are the first UHJs orbiting F-type stars with CO emission lines detected; previous detections were mostly for UHJs orbiting A-type stars. Evidence of weak H2O emission signals is also found for both planets. We further applied forward-model retrievals on the detected CO lines and retrieved the temperature-pressure profiles along with the CO volume mixing ratios. The retrieved logarithmic CO mixing ratio of WASP-18b (-2.2) is slightly higher than the value predicted by the self-consistent model assuming solar abundance. For WASP-76b, the retrieved CO mixing ratio (-3.6) is broadly consistent with the value of solar abundance. In addition, we included the equatorial rotation velocity (Veq ) in the retrieval when analyzing the line profile broadening. The obtained Veq is 7.0 km/s for WASP-18b and 5.2 km/s for WASP-76b, which are consistent with the tidally locked rotational velocities.


-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230228.0238

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230228.0235
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report

Surface environmental conditions

Nitrogen = 77.2 percent
Oxygen = 21.3 percent
Argon = 0.88 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.22 percent
Water vapor = 0 - 4 percent

Daystar condition = Thermal radiation within acceptable margins. Three sunspot-groupings detected with rather minor flares. Minimal elevated interference can be expected. Warming-up sequence at normal rate within range.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Brightened with 0.4 magnitudes.

Today's project : High-fidelity reaction kinetic modeling of hot-Jupiter atmospheres incorporating thermal and UV photochemistry enhanced by metastable CO(a3Pi)

A detailed modeling of simultaneous UV-photochemical and thermochemical processes in exoplanet atmosphere-like conditions is essential for the analysis and interpretation of a vast amount of current and future spectral data from exoplanets. However, a detailed reaction kinetic model that incorporates both UV photochemistry and thermal chemistry is challenging due to the massive size of the chemical system as well as to the lack of understanding of photochemistry compared to thermal-only chemistry. Here, we utilize an automatic chemical reaction mechanism generator to build a high-fidelity thermochemical reaction kinetic model later then incorporated with UV-photochemistry enhanced by metastable triplet-state carbon monoxide (a3Pi). Our model results show that two different photochemical reactions driven by Lyman-a photons (i.e. H2 + CO(a3Pi) -> H + HCO and CO(X1Sig+) + CO(a3Pi) -> C(3P) + CO2) can enhance thermal chemistry resulting in significant increases in the formation of CH4, H2O, and CO2 in H2-dominated systems with trace amounts of CO, which qualitatively matches with the observations from previous experimental studies. Our model also suggests that at temperatures above 2000 K, thermal chemistry becomes the dominant process. Finally, the chemistry simulated up to 2500 K does not produce any larger species such as C3 species, benzene or larger (i.e. PAHs). This might indicate that the photochemistry of C2 species such as C2H2 might play a key role in the formation of organic aerosols observed in the previous experimental study.


-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230303.0030

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230303.0025
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report.

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

The weather and environmental sensors are undergoing the last tests and seem to work just fine. Only the long range connection network shows some irregularities. This network is needed to transmit all important data to Tranquility in order to publish the daily environmental data report. Engineering has been asked to do the necessary.

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. No change in magnitude the last 24 hrs.

Today's project : The quintuple system 30 Arietis: Comments on orbital stability and habitability

The aim of this study is to investigate the potential of habitability for 30 Arietis, a quintuple stellar system located in the Northern Hemisphere. 30 Ari consists of two F-type main-sequence stars and three M dwarfs. The system is highly hierarchical; it encompasses one super-close binary and another binary of moderate separation distance accompanied by an outside component. Significant potential for circumstellar habitability exists regarding the super-close binary, as gauged by the size of the general habitable zone with a width of 1.85 au. Limited potential for habitability is found for the other part of the system given by 30 Ari C, but not for 30 Ari Ba+b. Hence, 30 Ari should be viewed as a system of intermediate relevance for future search missions of habitable exoplanets.

-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230306.0249

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230306.0025
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report.

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

Nitrogen = 77.4 percent
Oxygen = 21.3 percent
Argon = 0.87 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.23 percent
Water vapor = 0 - 4 percent

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Brightness rise with 0.22 magnitude.

Today's project : Improving circumbinary planet detections by fitting their binary’s apsidal precession

Apsidal precession in stellar binaries is the main non-Keplerian dynamical effect impacting the radial-velocities of a binary star system. Its presence can notably hide the presence of orbiting circumbinary planets because many fitting algorithms assume perfectly Keplerian motion. To first order, apsidal precession (⁠ω˙⁠) can be accounted for by adding a linear term to the usual Keplerian model. We include apsidal precession in the kima package, an orbital fitter designed to detect and characterise planets from radial velocity data. In this paper, we detail this and other additions to kima that improve fitting for stellar binaries and circumbinary planets including corrections from general relativity. We then demonstrate that fitting for ω˙can improve the detection sensitivity to circumbinary exoplanets by up to an order of magnitude in some circumstances, particularly in the case of multi-planetary systems. In addition, we apply the algorithm to several real systems, producing a new measurement of aspidal precession in KOI-126 (a tight triple system), and a detection of ω˙in the Kepler-16 circumbinary system. Although apsidal precession is detected for Kepler-16, it does not have a large effect on the detection limit or the planetary parameters. We also derive an expression for the precession an outer planet would induce on the inner binary and compare the value this predicts with the one we detect.

-- end log --

:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230307.0524

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230307.0035
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report.

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

Nitrogen = 77.3 percent
Oxygen = 21.2 percent
Argon = 0.88 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.26 percent
Water vapor = 0 - 4 percent

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Brightness rise with 0.13 magnitude.

Today's project : Coplanar Circumbinary Planets Can Be Unstable to Large Tilt Oscillations in the Presence of an Inner Polar Planet

Mutually misaligned circumbinary planets may form in a warped or broken gas disk or from later planet–planet interactions. With numerical simulations and analytic estimates we explore the dynamics of two circumbinary planets with a large mutual inclination. A coplanar inner planet causes prograde apsidal precession of the binary and the stationary inclination for the outer planet is higher for larger outer planet orbital radius. In this case a coplanar outer planet always remains coplanar. On the other hand, a polar inner planet causes retrograde apsidal precession of the binary orbit and the stationary inclination is smaller for larger outer planet orbital radius. For a range of outer planet semimajor axes, an initially coplanar orbit is librating meaning that the outer planet undergoes large tilt oscillations. Circumbinary planets that are highly inclined to the binary are difficult to detect—it is unlikely for a planet to have an inclination below the transit detection limit in the presence of a polar inner planet. These results suggest that there could be a population of circumbinary planets that are undergoing large tilt oscillations.

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:communicator: LtCmdr Ferre Flamand
User avatar
Ferre Flamand
Posts: 681
Joined: 211111.0543
Duty Post: Resigned 240301
Ship/Station Posted:
Grid: 001 Second Life
Location: Belgium
Has thanked: 266 times
Been thanked: 82 times
Contact:

230308.0954

Tranquility Station/Ops + Tranquility Science Lab - Stardate 230308.0025
Reporting Officer: LtCmdr Ferre Flamand
Other Officers on Duty: 6 NPC's

Duty Log - Daily Scientific and Observation Report.

Daystar condition = Thermal radiation within acceptable margins. Two sunspot-grouping detected with less active flares. No interference can be expected. Warming-up sequence at normal rate within range.

Nitrogen = 77.3 percent
Oxygen = 21.5 percent
Argon = 0.88 percent
Neon, Helium, Krypton = 0.0008 percent
Carbon dioxide = 0.23 percent
Water vapor = 0 - 4 percent

Betelgeuse (Alpha Orionis) its variable magnitude intervals within range. Brightness rise with 0.07 magnitude.

Today's project : Direct discovery of the inner exoplanet in the HD 206893 system

Aims. HD 206893 is a nearby debris disk star that hosts a previously identified brown dwarf companion with an orbital separation of ∼10 au. Long-term precise radial velocity (RV) monitoring, as well as anomalies in the system proper motion, has suggested the presence of an additional, inner companion in the system.

Methods. Using information from ongoing precision RV measurements with the HARPS spectrograph, as well as Gaia host star astrometry, we have undertaken a multi-epoch search for the purported additional planet using the VLTI/GRAVITY instrument.

Results. We report a high-significance detection over three epochs of the companion HD 206893c, which shows clear evidence for Keplerian orbital motion. Our astrometry with ∼50−100 μarcsec precision afforded by GRAVITY allows us to derive a dynamical mass of 12.7MJup and an orbital separation of 3.53 au for HD 206893c. Our fits to the orbits of both companions in the system use both Gaia astrometry and RVs to also provide a precise dynamical estimate of the previously uncertain mass of the B component, and therefore allow us to derive an age of 155 ± 15 Myr for the system. We find that theoretical atmospheric and evolutionary models that incorporate deuterium burning for HD 206893c, parameterized by cloudy atmosphere models as well as a “hybrid sequence” (encompassing a transition from cloudy to cloud-free), provide a good simultaneous fit to the luminosity of both HD 206893B and c. Thus, accounting for both deuterium burning and clouds is crucial to understanding the luminosity evolution of HD 206893c.

Conclusions. In addition to using long-term RV information, this effort is an early example of a direct imaging discovery of a bona fide exoplanet that was guided in part by Gaia astrometry. Utilizing Gaia astrometry is expected to be one of the primary techniques going forward for identifying and characterizing additional directly imaged planets. In addition, HD 206893c is an example of an object narrowly straddling the deuterium-burning limit but unambiguously undergoing deuterium burning. Additional discoveries like this may therefore help clarify the discrimination between a brown dwarf and an extrasolar planet. Lastly, this discovery is another example of the power of optical interferometry to directly detect and characterize extrasolar planets where they form, at ice-line orbital separations of 2−4 au.



-- end log --

:communicator: LtCmdr Ferre Flamand
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