HD 63433 Archives - Astrobiology

Simulated stellar wind of TOI-1860, DS Tuc A, and HD 63433 in the x⋆ −y⋆ plane. The rotation axis lies along the positive z⋆. The Alfvén surface is shown as a translucent surface and its intersection on the x⋆ −y⋆ plane is shown as a white curve. The colour bar indicates the total wind velocity. The orbits of the hosted exoplanets are also included as coloured ellipses. For HD 63433, we also show the simulations from the 2023 data analysed in Bellotti et al. (2024). -- astro-ph.SR

Ariel Mission, Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Missions & Hardware, Space Weather & Heliophysics, Status Report, Stellar Cartography

Spectropolarimetric Characterisation Of Exoplanet Host Stars In Preparation Of The Ariel Mission II. The magnetised wind environment of TOI-1860, DS Tuc A, and HD 63433

by Keith CowingDecember 27, 2025December 27, 2025

We update the status of the spectropolarimetric campaign dedicated to characterise the magnetic field properties of a sample of known exoplanet-hosting stars included in the current target list of the […]

Schematic view of the seven planetary systems studied in this work. In the upper panel, the location on the x-axis shows the orbital semi-major axis of the planets in question, on a linear scale, with the horizontal lines reaching out from the planet showing the range of its orbit from pericentre to apocentre. The size of the marker for each planet gives the observed radius, as presented in the discovery work, whilst the colour of the marker gives the measured mass for the planet. In the case of the planets orbiting HD 63433, no measured mass has been obtained to date, and we therefore plot an estimated mass for the two planets in that system, based on Figure 3 of Chen & Kipping (2017). In the case of TOI 1670 b, the mass given is an upper limit. The lower panel presents most of the same information (mass, radius, etc.), but shows the separation of the planetary systems in terms of their orbital periods, with the period of the inner planet in each system set to unity. The parent stars are shown sized relative to one another, but not to scale with their planets, and their colour in the plot denotes their effective temperatures, Teff. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

The Search For The Inbetweeners: How Packed Are TESS Planetary Systems?

by Keith CowingNovember 7, 2024November 7, 2024

In this work, we examine seven systems discovered by TESS, to see whether there is any room in those systems for an additional planet (or several) to lurk unseen between […]

The relative sizes of the three known planets in the HD 63433 system, with the young Earth-like planet with a lava surface closest to the star. The other two planets are mini-Neptunes. CREDIT Ben Capistrant

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Press Release

Young Earth-like Planet With Lava Oceans

by Keith CowingFebruary 27, 2024February 27, 2024

Astronomers have discovered an extreme Earth-like planet that likely hosts lava oceans as it roasts next to its sun-like star near the Big Dipper constellation.

The top panel shows the unflattened TESS light curve of HD 63433. The middle panel shows the flattened light curve with our three best-fit transit models for planets b, c, and d, as determined by our edmcmc outputs. The colors of these models correspond to each of the three planets as shown in the bottom panels, which depict the phase-folded light curves for each HD 63433 planet with binned data (red points) plotted over our best-fit models. -- astro-ph.EP

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Status Report

TESS Hunt For Young And Maturing Exoplanets (THYME) XI: An Earth-sized Planet Orbiting a Nearby, Solar-like Host in the 400Myr Ursa Major Moving Group

by Keith CowingJanuary 14, 2024January 14, 2024

Young terrestrial worlds are critical test beds to constrain prevailing theories of planetary formation and evolution. We present the discovery of HD 63433d – a nearby (22pc), Earth-sized planet transiting […]

HD 63433d is the third planet found in orbit around a star called HD 63433.

Astronomy & Telescopes, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release

Earth-sized Planet HD 63433d Discovered In Our Solar Backyard

by Keith CowingJanuary 13, 2024January 13, 2024

A team of astronomers have discovered a planet closer and younger than any other Earth-sized world yet identified. It’s a remarkably hot world whose proximity to our own planet and […]

Like Kepler-10 b, illustrated above, the exoplanet HD 63433 d is a small, rocky planet in a tight orbit of its star. HD 63433 d is the smallest confirmed exoplanet younger than 500 million years old. It's also the closest discovered Earth-sized planet this young, at about 400 million years old. NASA/Ames/JPL-Caltech/T. Pyle

Astrogeology, Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Exoplanets, -moons, -comets, Imaging & Spectroscopy, Press Release

Earth-sized Planet HD 63433 d Has A Lava Hemisphere

by Keith CowingJanuary 12, 2024January 12, 2024

The discovery: In a system with two known planets, astronomers spotted something new: a small object transiting across the Sun-sized star. This turned out to be another planet: extra hot […]

mini-Neptune TOI 560.01

Atmospheres, Climate, Weather, Exoplanets, -moons, -comets, Habitable Zones, Press Release

Puffy Planets Can Lose Their Atmospheres And Become Super-Earths

by Keith CowingMarch 7, 2023March 7, 2023

If our solar system were a hobbyist kit, it would come boxed up with four rocky terrestrial planets, like Earth; and four gas giant planets like Jupiter.