In this image the NASA/ESA Hubble Space Telescope takes a close look at the spiral galaxy NGC 4217, 60 million light-years away. The galaxy is seen almost perfectly edge on and is a perfect candidate for studying the nature of extraplanar dust structures — the patterns of gas and dust above and below the plane on the galaxy, seen here as brown wisps coming off NGC 4217.
These tentacle-like filaments are visible in the Hubble image only because the contrast with their surroundings is so high. This implies that the structures are denser than their surroundings. The image shows dozens of dust structures some of which reach as far as 7000 light-years away from the central plane. Typically the structures have a length of about 1000 light-years and are about 400 light-years in width.
Arp 87 is a stunning pair of interacting galaxies. Stars, gas, and dust flow from the large spiral galaxy, NGC 3808, forming an enveloping arm around its companion. The shapes of both galaxies have been distorted by their gravitational interaction. Arp 87 is located in the constellation of Leo, the Lion, approximately 300 million light-years away from Earth. Arp 87 appears in Arp’s Atlas of Peculiar Galaxies. As also seen in similar interacting galaxies, the corkscrew shape of the tidal material suggests that some stars and gas drawn from the larger galaxy have been caught in the gravitational pull of the smaller one. This image was taken in February 2007 with Hubble’s Wide Field Planetary Camera 2 detector.
Credit: NASA, ESA, and The Hubble Heritage Team (STScI/AURA)