Hubble finds new Neptune moon

NASA Hubble finds new Neptune moon
This composite Hubble Space Telescope picture shows the location of a newly discovered moon, designated S/2004 N 1, orbiting Neptune. The black and white image was taken in 2009 with Hubble's Wide Field Camera 3 in visible light. Hubble took the color inset of Neptune on August 2009. Credit: NASA, ESA, M. Showalter/SETI Institute

( —NASA's Hubble Space Telescope has discovered a new moon orbiting the distant blue-green planet Neptune, the 14th known to be circling the giant planet.

The moon, designated S/2004 N 1, is estimated to be no more than 12 miles across, making it the smallest known moon in the Neptunian system. It is so small and dim that it is roughly 100 million times fainter than the faintest star that can be seen with the naked eye. It even escaped detection by NASA's Voyager 2 spacecraft, which flew past Neptune in 1989 and surveyed the planet's system of moons and rings.

Mark Showalter of the SETI Institute in Mountain View, Calif., found the moon July 1, while studying the faint arcs, or segments of rings, around Neptune. "The moons and arcs orbit very quickly, so we had to devise a way to follow their motion in order to bring out the details of the system," he said. "It's the same reason a sports photographer tracks a running athlete—the athlete stays in focus, but the background blurs."

The method involved tracking the movement of a white dot that appears over and over again in more than 150 archival Neptune photographs taken by Hubble from 2004 to 2009.

Hubble finds new Neptune moon
This diagram shows the orbits of several moons located close to the planet Neptune. All of them were discovered in 1989 by NASA's Voyager 2 spacecraft, with the exception of S/2004 N 1, which was discovered in archival Hubble Space Telescope images taken from 2004 to 2009. The moons all follow prograde orbits and are nestled among Neptune's rings (not shown). The outer moon Triton was discovered in 1846 — the same year the planet itself was discovered. Triton's orbit is retrograde, suggesting it is a captured Kuiper Belt object and therefore a distant cousin of Pluto. The inner moons may have formed after Triton's capture several billion years ago. Credit: NASA, ESA, and A. Feild (STScI)

On a whim, Showalter looked far beyond the ring segments and noticed the white dot about 65,400 miles from Neptune, located between the orbits of the Neptunian moons Larissa and Proteus. The dot is S/2004 N 1. Showalter plotted a circular for the moon, which completes one revolution around Neptune every 23 hours.

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Jul 15, 2013
Over two decades later and Hubble still churning out new finds. Its legacy must be one of being mankind's greatest accomplishments.

Jul 15, 2013
Talk about a discovery of little consequence other than as a paean to Hubble.

Jul 16, 2013
Hubble...the Eveready Bunny of earth astronomy. But it IS a sign of our times that considering the exceptional performance of this device, a device that has found increasingly more difficult facts and truths about our universe on a dwindling supply of coolant, fuel, and money, that, someone has come to THIS site, to HATE ON the freaking Hubble Space Telescope.
All of humanity is NOT ready to visit other worlds my friends, hell no!
The noble and ingenious people who made this instrument of enlightenment are truly the pride of astronomy departments all over the world and their work is ONE MORE reason to save our planet folks.
What if everything ran, I say RAN, as well as the Hubble has performed? OMG! Opec would be out of business, aircraft would fly around the world without refuelling carrying small towns.
Different world.

Someday, the Hubble will fail and generations will see its images and wonder what a 'Hubble' is. A sad day indeed: A moment of silence...please....


Jul 16, 2013
Talk about a discovery of little consequence other than as a paean to Hubble.

Not an astronomer, but here's a couple guesses to contradict:

- Refining/proving a new technique for extracting information from image data. Which can then be applied to other sets of data.

- More data on moons in a Neptune-like environment, perhaps why/how something this small can exist, how long it's been there, is it stable, where it came from.

Jul 16, 2013
Talk about a discovery of little consequence other than as a paean to Hubble

Alfie made two good points already, and I would like to add a third:

This kind of detail is very difficult to see around other stars. By looking at our own system, we get clues about what other systems are likely to look like. You might find patterns and be able to chart out statistical things like ratios of various types of objects.

If you are only talking about the usefulness in terms of money and jobs, then I guess you're right, but that would be a very short sighted view. I'm personally glad that we challenge ourselves and expand the limits of our understanding in regard to our place in the Universe and its nature.

Jul 16, 2013
Kudos to the Hubble science team for finding Nemo

Jul 16, 2013
People who talk about how we need to "fund things here on Earth" and "get these physicists real jobs" take, at best, an extremely simplistic and Luddite view of the world. As pointed out earlier, techniques used in astronomy can subsequently be applied to the Earth; in addition, studying our galaxy and Universe is the best way to find locations where life may have emerged, and hence destinations for future human expansion. That will be a real job, not just for individuals but for civilization as a whole.

Jul 16, 2013
Kudos to the Hubble science team for finding Nemo

Now that's freakin' funny.

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