Discovery: New Moving Group in the Local Arm of the Milky Way

Recently, a research group of Prof. Gang Zhao from National Astronomical Observatories of Chinese Academy of Sciences (NAOC) has discovered a new stellar moving group near the Orion Nebula in the Milky Way, using the data of LAMOST DR5 and Gaia DR2. This research result has been published in the Astronomical Journal.

 

A moving group is a group of very loose stars, which is generally the remnant of a stellar association drift through the Milky Way. The detection and origin analysis of moving groups are of great significance for the understanding of the Galactic formation, structure, and evolution. Large samples of reliable data such as proper motion, radial velocity and distance are required for the detection, while advanced and effective detection methods are also important. The combination of the LAMOST huge spectral dataset and the Gaia astrometric data provides a unique advantage in detecting moving groups.

 

This newly discovered moving group contains a total of 206 member stars, 74 of which are pre-main sequence stars - protostars whose central hydrogen has not been ignited, and the rest are G- and K-type giant stars.

 

"According to the analysis, we find that the pre-main sequence stars in this moving group were formed in the Orion Nebula, while the G and K giants are in different evolutionary sequences compared with the stars in the Orion Nebula, so they were not born in the Orion Nebula,” said Xilong Liang, the first author of the paper who is a PhD student in NAOC. "The pre-main sequence member stars show that some of the stars formed in the Orion Nebula are moving out. The G and K giants may have gathered together as the arrival of the peak of the spiral-arm density wave, and now they are gradually spreading out as the peak of the density wave leaves."

 

"The discovery of this moving group provides an observational evidence for studying the possibility that the spiral-arm density wave drives the stars to gather and then trigger the collapse of the nebula. At the same time, located in the local spiral arm of the Milky Way, this moving group also provides a new sample to study the disruption of stellar groups," said Prof. Jingkun Zhao, a member of the research group.


 

Figure. The positions of the Orion Nebular, the local arm, and our Sun. (Credit: Wikipedia)

 

Link to the paper: https://doi.org/10.3847/1538-3881/ab7fa9.

Related accessories
Related documents
More Than a Thousand Carbon Stars Discovered in LAMOST DR4
Chinese telescope collects more than 11 mln spectra
LAMOST Released its Seventh Data (DR7) to the Public
LAMOST Released its Fourth Data(DR4)to the Public
DR6: LAMOST Spectra Entered the Era of Tens of Millions.
Searching the predecessor of the merging galaxy
LAMOST Released its Seventh Data (DR7) to the Public
Searching the predecessor of the merging galaxy
Chinese astronomers discover nearly 600 high-velocity stars
Chinese telescope collects more than 11 mln spectra
Chinese astronomers discover nearly 600 high-velocity stars
Chinese astronomers discovered 591 high velocity stars from LAMOST and Gaia
LAMOST Released its Sixth Data (DR6) internationally
Chinese astronomers discovered 591 high velocity stars from LAMOST and Gaia
DR6: LAMOST Spectra Entered the Era of Tens of Millions.
LAMOST Released its Fourth Data(DR4)to the Public
First Result of LAMOST High-Resolution Spectroscopy
Researchers estimated ages and metallicities of M31 star clusters from LAMOST DR6
LAMOST Released its DR8 Data
Researchers estimated ages and metallicities of M31 star clusters from LAMOST DR6
LAMOST Released its Sixth Data (DR6) internationally
LAMOST-Kepler/K2 Survey announced the first light result
LAMOST-Kepler/K2 Survey announced the first light result
More Than a Thousand Carbon Stars Discovered in LAMOST DR4
DR6: LAMOST Spectra Entered the Era of Tens of Millions.
LAMOST released its Seventh Data (DR7) internationally
LAMOST Released its DR8 Data
Exceeding 20 million: LAMOST Released its DR10 Data
LAMOST Released its Eighth Data (DR8) Internationally
Chinese astronomer discovers fastest rotating star in Milky Way
Chinese astronomer discovers fastest rotating star in Milky Way
LAMOST discovery of 135 new O-type stars
Correlation between planet occurrence and stellar dynamics discovered via LAMOST-Gaia data
Findings refine knowledge of galaxy
Chinese researchers constructed a largest lithium-rich giant sample based on the LAMOST data
Discovery of Two Nearby Young Stellar Associations in the Milky Way
LAMOST view of the temporal variability of stellar activity in young late-type stars
Chinese researchers constructed a largest lithium-rich giant sample based on the LAMOST data
LAMOST view of the temporal variability of stellar activity in young late-type stars
China and Europe together launch ESASky in Chinese
Discovery of Two Nearby Young Stellar Associations in the Milky Way
LAMOST: Expanding the Sample of Chemically Peculiar Stars
LAMOST discovers new type of compact binary star
A wobbly and flared Milky Way disk revealed with LAMOST-Gaia data
LAMOST helps Gaia to achieve mmag precision in photometry
First Investigation of the Local Properties of Sagittarius Stream with LAMOST Data
LAMOST helps to determine the parameters of 300,000 M dwarfs
The Blazing Sky: LAMOST Observations Reveal Nature of Unknown Gamma-ray Sources
First Investigation of the Local Properties of Sagittarius Stream with LAMOST Data
China and Europe together launch ESASky in Chinese
Discovery: New Moving Group in the Local Arm of the Milky Way
Planetary Census "Through" Time and Space Aided by LAMOST
LAMOST reveals the secret of stellar rotation of hot stars
LAMOST Data Reveals Alpha-rich "Young" Stars are Actually NOT Young
LAMOST helps to propose new method searching for clusters in Andromeda galaxy
Discovery of a Pre-ELM WD Binary by Using LAMOST
Chinese astronomers find galactic "fruit, vegetable garden" outside Milky Way
Extragalactic fruit and vegetable garden: compact galaxies discovered by LAMOST
Stellar Populations of Galaxies in the LAMOST Spectral Survey
Copyright © National Astronomical Observatories, Chinese Academy of Sciences
Address: 20A Datun Road, Chaoyang District, Beijing, China code: 100012
Tel: 010-64888708 E-mail: naoc@nao.cas.cn