At a Glance
- An international team of astronomers has discovered four new eruptive young stellar objects (YSOs) by analyzing data from the SPICY catalog and NASA’s WISE spacecraft.
- YSOs are stars in the early stages of evolution, and they undergo accretion-driven outbursts known as EX Lup and FU Ori outbursts.
- The researchers identified four eruptive YSOs, including two bona fide FUors and one candidate FUor with an ongoing outburst.
- All four newly discovered YSOs exhibit long-term, high-amplitude outbursts and display strong 12CO emission lines in their spectra.
- The study provides valuable insights into the accretion processes of YSOs and highlights the need for continued monitoring and follow-up observations of these objects.
A team of international astronomers has made an exciting discovery by analyzing data from the SPICY catalog and NASA‘s WISE spacecraft. They have identified four new eruptive young stellar objects (YSOs), stars in the early stages of evolution. The findings were published in the December issue of the Journal of the Korean Astronomical Society.
Young stellar objects (YSOs) are typically found within dense molecular clusters that contain molecular gas and interstellar particles. These objects, including protostars and pre-main sequence stars, undergo episodic accretion processes. This means they experience accretion-driven outbursts, which astronomers classify as EX Lup or FU Ori outbursts. EX Lup outbursts are smaller in magnitude and last from a few months to a couple of years, while FU Ori outbursts are more extreme, rare, and can last for decades or even centuries.
Given the rarity of eruptive young stellar objects and the limited number of known objects, a group of astronomers led by Carlos Contreras Peña from Seoul National University searched for new outbursting YSOs. They examined data from the SPICY catalog and analyzed mid-infrared photometry from the WISE mission.
As a result of their investigation, the researchers identified four eruptive YSOs: SPICY 97855, SPICY 99341, SPICY 100587, and SPICY 109331. SPICY 99341 and SPICY 100587 were classified as bona fide FUors, while SPICY 97855 is a candidate FUor with an ongoing outburst. SPICY 109331, initially classified as an EXor, displayed a longer outburst duration than expected and was classified as a V1647 Ori-like source, exhibiting mixed characteristics between EXors and FUors.
The study revealed that all four newly discovered eruptive YSOs exhibit long-term, high-amplitude outbursts lasting more than a year and with magnitudes exceeding 2.5. Their spectra also display strong 12CO emission lines, indicating significant changes in the accretion rate.
The distance to SPICY 99341 and SPICY 109331 was determined to be approximately 9,800 and 12,500 light-years, respectively. However, further observations are required to determine the distance to the other two YSOs accurately.
This discovery of four new eruptive YSOs provides valuable insights into young stellar objects’ accretion processes and behavior. Continued monitoring and follow-up observations of these objects will contribute to a better understanding of their accretion mechanisms.
References
- Contreras Peña, C., Ashraf, M., Lee, J.-E., Herczeg, G., Lucas, P., Guo, Z., Johnstone, D., Lee, H.-G., & Jose, J. (2023). New Eruptive YSOs from SPICY and WISE. Journal of The Korean Astronomical Society, 56(2), 253–262. https://doi.org/10.5303/JKAS.2023.56.2.253
- Nowakowski, T. & Phys.org. (2023, December 7). Four eruptive young stellar objects discovered. Phys.Org; Phys.org. https://phys.org/news/2023-12-eruptive-young-stellar.html
