A tidal shock occurs when a
star cluster
Star clusters are large groups of stars. Two main types of star clusters can be distinguished: globular clusters are tight groups of ten thousand to millions of old stars which are gravitationally bound, while open clusters are more loosely clust ...
or other distributed
astronomical object
An astronomical object, celestial object, stellar object or heavenly body is a naturally occurring physical entity, association, or structure that exists in the observable universe. In astronomy, the terms ''object'' and ''body'' are often us ...
passes by a large mass
such as an
interstellar cloud, resulting in
gravitational perturbation on a time scale that is much less than the mean time for a star to complete an orbit within the cluster. The
tidal force from this event can increase the dynamic energy of the cluster, in effect heating it up. This causes the cluster to expand and shed some of the outer stars.
[
Tidal shocks occur, for example, when a globular cluster passes through the galactic plane or near the core of the Milky Way. These events are an important factor during the early evolution of a globular cluster. They work to truncate the outer part of clusters, thereby limiting the impact of future tidal shocks.][ Streams of stars shed from a globular cluster as a result of tidal shock can form what are termed tidal tails. These are extended streams of stars that lead away from the cluster.][ Such streams can be used to trace the orbital path of the cluster.][
]
References
{{reflist, refs=
[{{cite journal , author=Ostriker, Jeremiah P. , author2=Spitzer, Lyman, Jr. , author3=Chevalier, Roger A. , title=On the Evolution of Globular Clusters , journal= Astrophysical Journal , volume=176 , page=L51 , date=September 1972 , doi=10.1086/181018 , bibcode=1972ApJ...176L..51O ]
[{{cite conference , author=Lee, Hyung Mok , title=The Life and Death of Globular Clusters , book-title=Extragalactic Star Clusters, IAU Symposium 207 , location=Pucon, Chile , date=March 12–16, 2001 , editor=D. Geisler , editor2=E.K. Grebel , editor3=D. Minniti , publication-place=San Francisco , publisher= Astronomical Society of the Pacific , publication-date=2002 , bibcode=2002IAUS..207..584L ]
[{{cite journal , title=The tidal tails of globular cluster Palomar 5 based on the neural networks method , author=Zou, Hu , author2=Wu, Zhen-Yu , author3=Ma, Jun , author4=Zhou, Xu , journal=Research in Astronomy and Astrophysics , volume=9 , issue=10 , pages=1131–1148 , date=October 2009 , doi=10.1088/1674-4527/9/10/005 , bibcode=2009RAA.....9.1131Z , arxiv = 0905.3614 , s2cid=8534666 ]
[{{cite journal , author=Yim, Ki-Jeong , author2=Lee, Hyung Mok , title=Tidal Tails of Globular Clusters , journal=Journal of the Korean Astronomical Society , volume=35 , issue=2 , pages=75–85 , date=June 2002 , bibcode=2002JKAS...35...75Y , doi = 10.5303/jkas.2002.35.2.075, doi-access=free ]
Globular clusters
Celestial mechanics