RCW 7 is located in the constellation Puppis, about 5,300 light years from Earth.
This Hubble image shows the nebula RCW 7. Image courtesy of NASA/ESA/Hubble/J. Tan, Chalmers University, University of Virginia.
“Nebulae are regions of space that are rich in the raw materials needed to form new stars,” the Hubble astronomers said.
“Due to the effects of gravity, some of these molecular clouds collapse and merge into protostars surrounded by a rotating disk of remaining gas and dust.”
“In the case of RCW 7, the protostar forming here is particularly massive, emitting intense ionizing radiation and a powerful stellar wind that propelled the star into a “H II region“.
“The H II regions are filled with hydrogen ions. HI refers to regular hydrogen atoms, and H II is hydrogen that has lost an electron.”
“Ultraviolet rays from the massive protostar excite the hydrogen, which then emits light that gives the nebula its soft pink glow.”
In RCW 7, the researchers IRAS 07299-1651.
“IRAS 07299-1651 still resides within a cocoon of glowing gas, in clouds swirling towards the top of the nebula,” the researchers said.
To expose this star and its sibling, the new image was created from separate exposures taken in the near-infrared region of the spectrum. Hubble’s Wide Field Camera 3 (WFC3).
“This massive protostar is most bright in ultraviolet light, but it also emits a lot of infrared light that penetrates much of the surrounding gas and dust and can be seen by the Hubble Telescope,” the scientists said.
“Many of the other large visible stars in this image are not part of the nebula, but are located between the nebula and the solar system.”
Assuming a circular orbit, IRAS 07299-1651 is estimated to have a minimum total mass of 18 times that of the Sun and a maximum period of 570 years.
“The formation of the H II region marks the beginning of the end of the molecular cloud,” the authors said.
“Over just a few million years, radiation and winds from the massive stars gradually disperse the gas, and this dispersion continues as the most massive stars end their lives in supernova explosions.”
“Only a small portion of this gas will be absorbed by new stars within the nebula, while the rest will spread throughout the galaxy and eventually form new molecular clouds.”
Team Investigation result Published in a journal Natural Astronomy.
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Y. Chan others2024. Dynamics of a giant binary star at birth. Nat Astron 3, 517-523; doi: 10.1038/s41550-019-0718-y
Source: www.sci.news
