About

Stars are called “massive” if their masses are in the range between ten and hundred suns. During most of their lifetime, such stars exhibit surface temperatures from 15 000 to 150 000 Kelvins (they are classified as spectral type O or B) and have luminosities larger than a few tens of thousands of solar luminosities. In fact, these stars are the true cosmic engines in the Universe. Indeed, they are the main sources of ionizing radiation, mechanical input, and chemical enrichment in most galaxies. They are also the progenitors of supernovae and gamma-ray bursts, as well as of neutron stars and black holes (and therefore also of gravitational wave events). The study of the properties of massive stars is therefore crucial for understanding the cosmos, its evolution, and its most energetic processes.

However, massive stars are quite rare: they are born few in number and live short lives (a few million years, to be compared to ten billions for the Sun). Therefore, many questions on their properties remain open. The GAPHE aims at answering them by using multiwavelength observations taken by ground-based (ESO, CAHA, OHP,...) and space-based (XMM-Newton, Gaia, TESS,...) observatories. The GAPHE also participates to the design of the next generations of instruments to prepare the future of observational astronomy.

You want to know more? Just take a look at our research  pages!