GRAVITY observations reveal that most massive stars in the Orion Trapezium cluster live in multiple systems. Our deep, milliarcsecond-resolution interferometry fills the gap at 1─100 astronomical units (au), which is not accessible to traditional imaging and spectroscopy, but is crucial to uncovering the mystery of high-mass star formation.The new

We report the discovery of a gas-giant planet orbiting a low-mass host star in the microlensing event MOA-bin-29 that occurred in 2006. We find five degenerate solutions with the planet/host-star mass ratio of q ∼ 10 −2. The Einstein radius crossing time of all models are relatively short (∼4─7 days), which indicates that the mass of host star is

While the formation of stellar clumps in distant galaxies is usually attributed to gravitational violent disk instabilities, we show here that major mergers also represent a competitive mechanism to form bright clumps. Using ̃0.1″ resolution ACS F814W images in the entire COSMOS field, we measured the fraction of clumpy emission in 109 main