哈勃观测到一处承受压力的星系

ESA/Hubble & NASA, M. Sun

This NASA/ESA Hubble Space Telescope image shows LEDA 42160, a galaxy about 52 million light-years from Earth in the constellation Virgo. The dwarf galaxy is one of many forcing its way through the comparatively dense gas in the massive Virgo cluster of galaxies. The pressure exerted by this intergalactic gas, known as ram pressure, has dramatic effects on star formation in LEDA 42160.

The gas and dust that permeates space exerts pressure on a galaxy as it moves. This resistance, called ram pressure, can strip a galaxy of its star-forming gas and dust, reducing or even stopping the creation of new stars. However, ram pressure can also compress gas in the galaxy, which can boost star formation.

The Hubble data used to create this image of LEDA 42160 is part of a project that studied dwarf galaxies undergoing ram pressure stripping that are part of large galaxy clusters, like the Virgo cluster. Studies show that ram pressure stripping can initially cause new stars to form in larger galaxies. The researchers wanted to see if the same holds true for smaller galaxies, like LEDA 42160. The bright patches on LEDA 42160’s lower-right flank may be star-forming regions spurred on by ram pressure stripping. Hubble’s observations of LEDA 42160 will help astronomers determine the processes that created the features we see in this small galaxy.

这张由NASA/ESA哈勃空间望远镜拍摄的图像展示了LEDA 42160，一处位于处女座内，距离地球约5,200万光年的星系。这个矮小星系是许多穿行于质量庞大的处女座星系团相对稠密的气体中的星系之一。这种由星际气体施加的压力，称为冲压（ram pressure），对LEDA 42160中的恒星形成有着巨大的影响。

弥漫在太空中的气体和尘埃在星系运动时会对其施加压力。这种压力被称为冲压，它可以剥夺星系的恒星形成气体和尘埃，减少甚至阻止新恒星的产生。然而，冲压也会压缩星系中的气体，从而促进恒星的形成。

用于创建LEDA 42160图像的哈勃数据是一个项目的一部分，该项目研究了经历冲压剥离的矮星系，这些星系是如处女座星系团这样的大型星系团的一部分。研究表明，冲压剥离最初可以在大型星系中引发新恒星的形成。研究者们想要看看同样的情况是否也适用于像LEDA 42160这样的较小星系。LEDA 42160下右侧的明亮区域可能是由冲压剥离激发的恒星形成区域。哈勃对LEDA 42160的观测将帮助天文学家确定我们在这个小星系中看到的特征的形成过程。