First Doppler Limits on Binary Planets and Exomoons in the HR 8799 System

We place the first constraints on binary planets and exomoons from Doppler monitoring of directly imaged exoplanets. We model radial velocity observations of HR 8799 b, c, and d from Ruffio et al. and determine upper limits on the m sin i of short-period binary planets and satellites. At 95% confidence, we rule out companions orbiting the three planets more massive than m sin i = 2 M J with orbital periods shorter than 5 days. We achieve our tightest constraints on moons orbiting HR 8799c, where with 95% confidence we rule out out edge-on Jupiter-mass companions in periods shorter than 5 days and edge-on half-Jupiter-mass moons in periods shorter than 1 day. These radial velocity observations come from spectra with resolution 20 times lower than typical radial velocity instruments and were taken using a spectrograph that was designed before the first directly imaged exoplanet was discovered. Similar data sets from new and upcoming instruments will probe significantly lower exomoon masses.

Songverse: a music-loop authoring tool based on Virtual Reality

We can define Digital Musical Instruments (DMIs) as hardware-software solutions that are interactive and crafted to output sound according to users' input. DMIs are well known to unleash users' creativity but also to allow different and innovative experiences for the creation process, for example, smoothing the learning curve towards musical concepts such as rhythm and composition. On the other hand, Virtual Reality (VR) allows users to explore spatial interfaces in a natural and limitless way, which shows potential synergy towards the rise of new DMIs. In this paper, we introduce Songverse, an immersive DMI placed in a Virtual Reality scenario that allows users to create music by interacting with an environment designed to resemble the outer space. By adding systems, planets, and satellites to the virtual environment, the user can shape the produced sound through interactions that were extensively tested during the development phase. We then evaluated the instrument with musicians and non-musicians by interviewing and applying the System Usability Scale (SUS) to assess the easiness for people to create music using Songverse. As a result, users reported the use of the DMI as intuitive and easy to use, also highlighting the produced song as enjoyable.

Magnetic field of the Hot Earth. Reversals, magnetic anomalies and mechanism of the magnetic poles drift.

Principally new model of the magnetic field of the Hot Earth is proposed. Unlike the commonly accepted approach which considers that the Earth’s temperature doesn’t increase because heat released under selfgravitation is removed through radiation our model assumes that early substance of the Earth heated up to 30 000 K was a superheated and overcompressed vapour. Cooling the Earth substance was condensing. The system was expanding adiabatically that governed the character of the Earth enlargement. This scheme origins from the phase transition (PT) of condensation-evaporation under the benefit of condensation. PT provides the heat, geodynamics of expansion and the Earth’s magnetic field (EMF). The high temperature of the substance causes its thermoionization, whereas PT operation relating to mass transfer initiates charges separation and generation of the double electric layer (DEL). A diurnal rotation of DEL induces a weak initial EMF which enhances then at the expense of the Hall dynamo (Hall current) inside PT area. The benefit of evaporation causes the Earth compression and reversal of the EMF polarity. The approach we develop provides an insight into features of the magnetic field of the planets and satellites at the Sun system.

Biosignatures in the solar system

Humanity's interest in whether or not we are alone in the universe spans generations, from Giordano Bruno's 16th century musings on other worlds and Giovanni Schiaparelli reporting seeing ‘canali’ in 1877 on the surface of Mars (which were thought to have been created by intelligent life) to alien invasions portrayed in today's movies. However, it is still unclear if other planetary bodies are capable of supporting life. In the search for life there are two broad areas we look into, the requirements of life and actual signs of life. The identification of the key requirements for life enables scientists to focus life detection efforts onto planets and satellites that are considered habitable and more likely to support life. However, our ability to find life or detect signs of life is based on our understanding of life on Earth.