9969 Braille is a small Mars crossing asteroid that orbits the
SunThe Sun is the star at the center of the Solar System. The Earth and other matter orbit the Sun, which by itself accounts for about 99.86% of the Solar System's mass....
once every 3.58 years. It was discovered in 1992 by astronomers at
Palomar observatoryPalomar Observatory , at approximately 5,570 ft elevation, is a privately owned observatory located in San Diego County, California, 90 miles southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology...
and later named after
Louis BrailleLouis Braille was the inventor of braille, a world-wide system used by blind and visually impaired people for reading and writing. Braille is read by passing the fingers over characters made up of an arrangement of one to six embossed points...
, the inventor of the
writing system for the blindThe Braille system is a method that is widely used by blind people to read and write. Braille was devised in 1821 by Louis Braille, a blind Frenchman. Each Braille character or cell is made up of six dot positions, arranged in a rectangle containing two columns of three dots each...
. It was photographed in closeup by the spacecraft
Deep Space 1Deep Space 1 of the NASA New Millennium Program is a spacecraft dedicated to testing its payload of advanced, high risk technologies. Launched on 24 October 1998, three of twelve technologies on board had to work within a few minutes of separation from the carrier rocket for the mission to...
in 1999, but a malfunction resulted in indistinct images.
Discovered on May 27, 1992 by E. F. Helin and K. J. Lawrence working at the
Palomar observatoryPalomar Observatory , at approximately 5,570 ft elevation, is a privately owned observatory located in San Diego County, California, 90 miles southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology...
as part of NASA's
Planet-Crossing Asteroid SurveyThe Palomar Planet Crossing Asteroid Survey was initiated by Eleanor F. Helin and Eugene M. Shoemaker in 1973. This program is responsible for the discovery of several thousand asteroids of all types including a large number of Near-Earth Asteroids , over 200 high inclination objects, other rare...
, it was given the provisional designation
1992 KD.
9969 Braille is a small Mars crossing asteroid that orbits the
SunThe Sun is the star at the center of the Solar System. The Earth and other matter orbit the Sun, which by itself accounts for about 99.86% of the Solar System's mass....
once every 3.58 years. It was discovered in 1992 by astronomers at
Palomar observatoryPalomar Observatory , at approximately 5,570 ft elevation, is a privately owned observatory located in San Diego County, California, 90 miles southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology...
and later named after
Louis BrailleLouis Braille was the inventor of braille, a world-wide system used by blind and visually impaired people for reading and writing. Braille is read by passing the fingers over characters made up of an arrangement of one to six embossed points...
, the inventor of the
writing system for the blindThe Braille system is a method that is widely used by blind people to read and write. Braille was devised in 1821 by Louis Braille, a blind Frenchman. Each Braille character or cell is made up of six dot positions, arranged in a rectangle containing two columns of three dots each...
. It was photographed in closeup by the spacecraft
Deep Space 1Deep Space 1 of the NASA New Millennium Program is a spacecraft dedicated to testing its payload of advanced, high risk technologies. Launched on 24 October 1998, three of twelve technologies on board had to work within a few minutes of separation from the carrier rocket for the mission to...
in 1999, but a malfunction resulted in indistinct images.
Discovery and naming
Discovered on May 27, 1992 by E. F. Helin and K. J. Lawrence working at the
Palomar observatoryPalomar Observatory , at approximately 5,570 ft elevation, is a privately owned observatory located in San Diego County, California, 90 miles southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. It is owned and operated by the California Institute of Technology...
as part of NASA's
Planet-Crossing Asteroid SurveyThe Palomar Planet Crossing Asteroid Survey was initiated by Eleanor F. Helin and Eugene M. Shoemaker in 1973. This program is responsible for the discovery of several thousand asteroids of all types including a large number of Near-Earth Asteroids , over 200 high inclination objects, other rare...
, it was given the provisional designation
1992 KD. Later, it was renamed Braille in honour of
Louis BrailleLouis Braille was the inventor of braille, a world-wide system used by blind and visually impaired people for reading and writing. Braille is read by passing the fingers over characters made up of an arrangement of one to six embossed points...
as suggested by
Kennedy Space CenterThe John F. Kennedy Space Center is the NASA space vehicle launch facility and Launch Control Center on Merritt Island, Brevard County, Florida, United States. The site is near Cape Canaveral, midway between Miami and Jacksonville, Florida. It is long and around wide, covering . A total of...
software engineerA software engineer is a person who applies the principles of software engineering to the design, development, testing, and evaluation of the software and systems that make computers or anything containing software, such as chips, work.- Overview :...
Kerry Babcock in The Planetary Society's contest titled "Name That Asteroid".
Orbit
Braille has an unusually inclined orbit, and belongs to the somewhat rare class of asteroids known as Mars crossing asteroids. Simulations of its
orbitIn physics, an orbit is the gravitationally curved path of one object around a point or another body, for example the gravitational orbit of a planet around a star....
by scientists of the Deep Space 1 project predict that it will evolve into an Earth crossing orbit sometime around 6000 CE. Although its closest approach to the
SunThe Sun is the star at the center of the Solar System. The Earth and other matter orbit the Sun, which by itself accounts for about 99.86% of the Solar System's mass....
is closer than
MarsMars is the fourth planet from the Sun in the Solar System. The planet is named after Mars, the Roman god of war. It is also referred to as the "Red Planet" because of its reddish appearance, due to iron oxide prevalent on its surface....
orbit, its highly elliptical orbit takes it almost half-way to
JupiterJupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with a mass slightly less than one-thousandth that of the Sun but is two and a half times the mass of all of the other planets in our Solar System combined. Jupiter is classified as a gas...
at its apoapsis, and as such its
semi-major axisIn geometry, the semi-major axis is used to describe the dimensions of ellipses and hyperbolae.- Ellipse :The major axis of an ellipse is its longest diameter, a line that runs through the centre and both foci, its ends being at the widest points of the shape...
is too large for it to be classified as an
Amor asteroidThe Amor asteroids are a group of near-Earth asteroids named after the asteroid 1221 Amor. They approach the orbit of the Earth from beyond, but do not cross it. Most Amors do cross the orbit of Mars...
.
Physical characteristics
Braille is a
Q-type asteroidQ-type asteroids are relatively uncommon inner-belt asteroids with a strong, broad 1 micrometre olivine and pyroxene feature, and a spectral slope that indiciates the presence of metal...
, composed mostly of
olivineThe mineral olivine is a magnesium iron silicate with the formula
2SiO
4...
and
pyroxeneThe pyroxenes are a group of important rock-forming silicate minerals found in many igneous and metamorphic rocks. They share a common structure consisting of single chains of silica tetrahedra and they crystallize in the monoclinic and orthorhombic systems...
. Early ground based observations had suggested that it could have been a
V-type asteroidThe spectra of the V-type asteroids or Vestoids are similar to that of 4 Vesta, by far the largest asteroid in this class ....
with similarities of composition between it and the much larger
4 Vesta4 Vesta is the second most massive object in the asteroid belt, with a mean diameter of about 530 km and an estimated mass of 9% of the mass of the entire asteroid belt...
. The asteroid is irregularly shaped, measuring approximately 2.1 km × 1 km × 1 km.
Exploration
Detailed information about Braille comes primarily from the
Deep Space 1Deep Space 1 of the NASA New Millennium Program is a spacecraft dedicated to testing its payload of advanced, high risk technologies. Launched on 24 October 1998, three of twelve technologies on board had to work within a few minutes of separation from the carrier rocket for the mission to...
probe, which passed within 26 km of the asteroid on July 29, 1999, and from extensive ground based observations done in conjunction with the mission. By the time Deep Space 1 reached Braille, its
ultravioletUltraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than x-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV...
spectrometerA spectrometer is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum, typically used in spectroscopic analysis to identify materials. The variable measured is most often the light's intensity but could also, for instance, be the polarization...
had failed, but it did return two
CCDA charge-coupled device is a device for the movement of electrical charge, usually from within the device to an area where the charge can be manipulated, for example conversion into a digital value. This is achieved by "shifting" the signals between stages within the device one at a time...
images of medium resolution and three
infraredInfrared radiation is electromagnetic radiation whose wavelength is longer than that of visible light , but shorter than that of terahertz radiation and microwaves...
spectraSpectra are conditions or values that vary over a continuum.Spectra may also refer to:* Sally Spectra, a fictional character on The Bold and the Beautiful* Kia Spectra, a car developed by Kia Motors from 2000-present...
during the encounter. However, although the probe came within 26 km of Braille, the images and
spectraThe electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. The "electromagnetic spectrum" of an object is the characteristic distribution of electromagnetic radiation emitted or absorbed by that particular object....
were taken from an approximate distance of 14 000km, due to problems with the tracking system.
The main purpose of the Deep Space 1 mission was technology testing, but the encounter with Braille was of strong scientific value. No lone asteroid as small as Braille had previously been observed from such a short distance.
External links