Discovery images of
Nix and Hydra
Nix
is a non-
spherical
moon
of
Pluto
. It was found along with
Hydra
in June 2005 by the
Hubble Space Telescope
Pluto Companion Search Team.
The discovery images were taken on May 15, 2005 and May 18, 2005; the moons were independently found by Max J. Mutchler on June 15, 2005 and Andrew J. Steffl on August 15, 2005. The discoveries were announced on October 31, 2005, after confirmation from photographs archived in 2002. The moon were designated
S/2005 P 1
(Hydra) and
S/2005 P 2
(Nix).
[8]
[9]
The moon follows a circular orbit in the same plane as
Charon
. It takes 24.9 days to circle around Pluto.
Before its size was directly measured, the moon was calculated to have a diameter of between 46 km, if its
reflectivity
is similar to Charon's 35%, and 137 km, if it had a reflectivity of 4%, like the darkest
Kuiper belt
objects.
[10]
Nix is slightly fainter than
Hydra
, suggesting that it is somewhat smaller in size.
[7]
In the discovery image, Nix is 6,300 times fainter than Pluto.
[11]
Early research appeared to show that Nix was reddish like
Pluto
and unlike the other moons,
[12]
but more recent reports have been that it is grey like the remaining moons.
[7]
Nix was visited along with Pluto by the
New Horizons
mission in 2015.
The formal name "Nix", from the Greek
goddess
of
darkness
and
night
, and mother of Charon, was announced on June 21, 2006 on IAU Circular 8723,
[9]
where the designation
Pluto II
is also given. Together with Hydra, Pluto's third moon, the initials are those of the
New Horizons
probe. The initial proposal was to use the
Classical
spelling
Nyx
, but to avoid confusion with the
asteroid
3908 Nyx
, this was changed to "the Egyptian spelling of the Greek name".
[13]
- ↑
Jennifer Blue (2009-11-09).
"Gazetteer of Planetary Nomenclature"
. IAU Working Group for Planetary System Nomenclature (WGPSN)
. Retrieved
2010-08-30
.
- ↑
2.0
2.1
Stern, S. A.; Bagenal, F.; Ennico, K.; Gladstone, G. R.; et al. (15 October 2015). "The Pluto system: Initial results from its exploration by New Horizons".
Science
.
350
(6258): aad1815.
arXiv
:
1510.07704
.
Bibcode
:
2015Sci...350.1815S
.
doi
:
10.1126/science.aad1815
.
PMID
26472913
.
S2CID
1220226
.
- ↑
Showalter, M. R.
; Hamilton, D. P. (3 June 2015). "Resonant interactions and chaotic rotation of Pluto's small moons".
Nature
.
522
(7554): 45?49.
Bibcode
:
2015Natur.522...45S
.
doi
:
10.1038/nature14469
.
PMID
26040889
.
S2CID
205243819
.
- ↑
4.0
4.1
4.2
"2016 Lunar & Planetary Science Conference by National Institute of Aerospace"
. Archived from
the original
on 2018-06-23
. Retrieved
2018-02-16
.
- ↑
Northon, Karen (3 June 2015).
"NASA's Hubble Finds Pluto's Moons Tumbling in Absolute Chaos"
.
- ↑
6.0
6.1
"DPS 2015: Pluto's small moons Styx, Nix, Kerberos, and Hydra [UPDATED]"
.
www.planetary.org
.
- ↑
7.0
7.1
7.2
Stern S.A.; et al. (2006). "
The Positions, Colors, and Photometric Variability of Pluto's Small Satellites from HST Observations 2005-2006
".
Astronomical Journal
: submitted.
(
Final preprint
)
- ↑
IAU Circular No. 8625
describing the discovery
- ↑
9.0
9.1
IAU Circular No. 8723
naming the moons
- ↑
H. A. Weaver; S. A. Stern; M. J. Mutchler; A. J. Steffl; et al. (23 February 2006).
"Discovery of two new satellites of Pluto"
.
Nature
.
439
(7079): 943?945.
arXiv
:
astro-ph/0601018
.
Bibcode
:
2006Natur.439..943W
.
doi
:
10.1038/nature04547
.
PMID
16495991
.
S2CID
1456215
.
- ↑
Brightness Difference on 2005-05-15: (5th root of 100) ^ (Nix
APmag
23.38 - Pluto APmag 13.87) = 6,368x
- ↑
Buie, Marc W.; Grundy, William M.; Young, Eliot F.; Young, Leslie A.; Stern, S. Alan (2006).
"Orbits and Photometry of Pluto's Satellites: Charon, S/2005 P1, and S/2005 P2"
.
Astronomical Journal
.
132
(1): 290?298.
arXiv
:
astro-ph/0512491
.
Bibcode
:
2006AJ....132..290B
.
doi
:
10.1086/504422
.
S2CID
119386667
.
(
Final preprint
)
a, i, e
per
JPL
(site updated 2008 Aug 25)
- ↑
"Planet and Satellite Names and Discoverers"
.
Gazetteer of Planetary Nomenclature
. USGS Astrogeology. July 21, 2006
. Retrieved
2006-08-15
.
|
---|
Generally listed in increasing distance from Pluto. Temporary names in
italics
.
|
|