The NASA/ESA Hubble Space Telescope sees galaxies of all shapes, sizes, brightnesses, and orientations in the cosmos. Sometimes, the telescope gazes at a galaxy oriented sideways — as shown here. The spiral galaxy featured in this Picture of the Week is called NGC 3717, and it is located about 60 million light-years away in the constellation of Hydra (The Sea Serpent). 

Seeing a spiral almost in profile, as Hubble has here, can provide a vivid sense of its three-dimensional shape. Through most of their expanse, spiral galaxies are shaped like a thin pancake. At their cores, though, they have bright, spherical, star-filled bulges that extend above and below this disc, giving these galaxies a shape somewhat like that of a flying saucer when they are seen edgeon.

NGC 3717 is not captured perfectly edge-on in this image; the nearer part of the galaxy is tilted ever so slightly down, and the far side tilted up. This angle affords a view across the disc and the central bulge (of which only one side is visible). 

This illustration compares the atmospheres of two 'hot Jupiter'-class exoplanets orbiting very closely to different sunlike stars. The planets are too far away for the NASA/ESA Hubble Space Telescope to resolve any details. Instead, astronomers measured how the light from the parent stars is filtered through each planet's atmosphere. Hubble was used to measure the spectral fingerprint caused by the presence of water vapor in the atmosphere. The planet HAT-P-38 b did have a water signature, indicating the upper atmosphere is free of clouds or hazes. By contrast, a very similar hot Jupiter, WASP-67 b, showed no water vapor, suggesting that most of the planet's atmosphere is masked by high-altitude clouds.

These results are not peer-reviewed and were presented at the 230th meeting of the AAS.