Slideshow: Astronauts' Hubble picks

Each of the seven astronauts on Atlantis' mission to upgrade the Hubble Space Telescope has a favorite view of the universe, as seen by the orbiting observatory. Atlantis commander Scott Altman says Hubble's imagery "connects with people on a very visceral level." Find out which of Hubble's more than 570,000 images have connected with Altman and his crewmates.


- Adapted from Space.com

Atlantis commander Scott Altman says Hubble's view of two colliding juggernauts - nicknamed the "Mice galaxies" - is his personal favorite. The picture was taken in 2002, just after a servicing mission that Altman led. It shows the two galaxies - each sporting a long tail (hence the nickname) - as they close in on each other 300 million light-years from Earth in the constellation Coma Berenices. "Just thinking about that being out there amazes me," Altman says.

Hubble's stellar views of the Cat's Eye nebula, a distant planetary nebula first spotted by the telescope in 1994, take center stage for Atlantis pilot Gregory C. Johnson. "The picture is just astounding," Johnson says. The Cat's Eye nebula sits about 3,000 light-years from Earth in the constellation Draco. The nebula's concentric rings are the result of eruptions from its central star. This is a composite version of the image, blending data from Hubble (red and purple) and the Chandra X-ray Observatory (blue).

For U.S. Air Force Col. Michael Good, part of the Hubble mission's spacewalking team, the Hubble Ultra Deep Field exemplifies the telescope's cosmic vision. The picture, based on data from 2003 and 2004, shows 10,000 galaxies in a patch of sky in the constellation Fornax - including galaxies that emerged just 700 million years after the big bang. "To literally be looking at the first light of the universe, I think that's a pretty interesting and pretty amazing capability," Good says. But he says his absolute favorite picture will be "the next image we get from the telescope after we leave."

Shuttle robotic arm expert Megan McArthur says the sheer wealth of imagery collected by the Hubble Space Telescope over the past 19 years is much richer than a single snapshot. "I think that, in general, almost every picture I see is my favorite," she says. "They're all just awe-inspiring to me. I really can't pick just a single one."

Spacewalk repair chief John Grunsfeld, a "Hubble hugger" who is making his fifth spaceflight and third trip to the telescope, said the image closest to his heart is a snapshot of a pair of galaxies caught in the act of colliding. The image depicts the Tadpole galaxy, known as UGC 10214, which Hubble spotted after it had been walloped by a smaller galaxy. The Tadpole's trademark tail stretches 280,000 light-years away from the collision. The image was one of the first released after Hubble's 2002 service call, which Grunsfeld also flew on.

Veteran Hubble spacewalker Michael Massimino says the Cone Nebula is his favorite. Like the Mice galaxies and the Tadpole galaxy, it was among the first images released after Hubble's STS-109 servicing flight in 2002, which Massimino participated in with Grunsfeld and Altman. The Cone Nebula, or NGC 2264, sits about 2,500 light-years from Earth in the constellation Monoceros. "I liked it because it was beautiful, but also because we put the camera in correctly," Massimino says.

First-time spaceflier Andrew Feustel says he favors this image of three interacting galaxies, which was released recently to mark Hubble's 19th birthday. The grouping, known as Arp 194, sits about 600 million light-years from Earth in the constellation Cepheus. Feustel says the "Cosmic Fountain" image reminds him of a cosmic question mark. "I think it's Hubble's way of asking us what's next," Feustel says. "I'm curious to see what's next as well."


Learn more about the astronauts' favorite images at Space.com.