PDS 70 is a very young T Tauri star in the constellation Centaurus. Located 370 light-years from Earth, it has a mass of 0.76 M☉ and is approximately 5.4 million years old. The star has a protoplanetary disk containing two nascent exoplanets, named PDS 70b and PDS 70c, which have been directly imaged by the European Southern Observatory's Very Large Telescope. PDS 70b was the first confirmed protoplanet to be directly imaged.
The protoplanetary disk of PDS 70 with new planet PDS 70b (right)
ALMA image of a resolved circumplanetary disk around exoplanet PDS 70c
James Webb Space Telescope spectrum of PDS 70, detecting water in the terrestrial region of the protoplanetary disk
Hubble image of PDS 70. This is only the second multi-planet system to be directly imaged.
T Tauri stars (TTS) are a class of variable stars that are less than about ten million years old. This class is named after the prototype, T Tauri, a young star in the Taurus star-forming region. They are found near molecular clouds and identified by their optical variability and strong chromospheric lines. T Tauri stars are pre-main-sequence stars in the process of contracting to the main sequence along the Hayashi track, a luminosity–temperature relationship obeyed by infant stars of less than 3 solar masses (M☉) in the pre-main-sequence phase of stellar evolution. It ends when a star of 0.5 M☉ or larger develops a radiative zone, or when a smaller star commences nuclear fusion on the main sequence.
Artist's impression of a T Tauri star with a circumstellar accretion disc
Protoplanetary discs in the Orion Nebula