Following
the spacecraft's detection of Pluto's giant moon Charon in July 2013
and Pluto's smaller moons Hydra and Nix in July 2014 and January 2015,
respectively, New Horizons is now within sight of all the known members
of the Pluto system.
For the first time, NASA's New Horizons
spacecraft has photographed Kerberos and Styx - the smallest and
faintest of Pluto's five known moons.
It completes the Pluto
family as of now. If the spacecraft observes any additional moons as it
gets closer to Pluto, they will be worlds that no one has seen before.
"New
Horizons is now on the threshold of discovery," said John Spencer,
mission science team member from the Southwest Research Institute in
Boulder, Colorado.
Following the spacecraft's detection of Pluto's
giant moon Charon in July 2013 and Pluto's smaller moons Hydra and Nix
in July 2014 and January 2015, respectively, New Horizons is now within
sight of all the known members of the Pluto system.
Drawing ever
closer to Pluto in mid-May, New Horizons will begin its first search for
new moons or rings that might threaten the spacecraft on its passage
through the Pluto system.
The images of faint Styx and Kerberos are
allowing the search team to refine the techniques they will use to
analyze those data, which will push the sensitivity limits even deeper.
Kerberos and Styx were discovered in 2011 and 2012, respectively, by New Horizons team members using the Hubble Space Telescope.
Styx,
circling Pluto every 20 days, is likely just seven-21 kms in diameter
and Kerberos, with a 32-day period, is just 10-30 km in diameter.
The
images detecting Kerberos and Styx were taken with New Horizons' most
sensitive camera, the Long Range Reconnaissance Imager (LORRI).
"Detecting
these tiny moons from a distance of more than 55 million miles is
amazing," added New Horizons principal investigator Alan Stern.
Other
unlabeled features in the processed images include the imperfectly
removed images of background stars and other residual artifacts.
No comments:
Post a Comment