NASA Symposium Marks 50 Years Of Solar System Exploration
WASHINGTON
-- Media representatives are invited to attend a NASA History symposium
about past, present and future solar system exploration. The event
takes place Oct. 25-26 from 8:30 a.m. - 5 p.m. EDT, at the Lockheed
Martin Global Vision Center in Crystal City, Va.
The event is free and open to the public with prior registration. The deadline for registration is Friday, Oct. 19 at 5 p.m. The two-day event will be streamed live on the agency's website at:
The event is free and open to the public with prior registration. The deadline for registration is Friday, Oct. 19 at 5 p.m. The two-day event will be streamed live on the agency's website at:
The Solar System Exploration @ 50 Symposium will explore the milestones of our 50-year history of planetary exploration, what we have learned, and how we have learned it. The symposium is sponsored by the NASA History Program Office and the Science Mission Directorate at NASA Headquarters in Washington, NASA's Jet Propulsion Laboratory in Pasadena, Calif., and the Smithsonian's National Air and Space Museum in Washington.
Media representatives interested in attending should email Dwayne Brown at
Yvette Smith at
For a complete list of speakers and to register, visit:
Mariner 2
NSSDC ID: 1962-041A
Description
The Mariner 2 spacecraft was the second of a series of spacecraft used
for planetary exploration in the flyby, or nonlanding, mode and the
first spacecraft to successfully encounter another planet. Mariner 2 was
a backup for the Mariner 1 mission which failed shortly after launch to
Venus. The objective of the Mariner 2 mission was to fly by Venus and
return data on the planet's atmosphere, magnetic field, charged particle
environment, and mass. It also made measurements of the interplanetary
medium during its cruise to Venus and after the flyby.
Spacecraft and Subsystems
Mariner 2 consisted of a hexagonal base, 1.04 meters across and 0.36
meters thick, which contained six magnesium chassis housing the
electronics for the science experiments, communications, data encoding,
computing, timing, and attitude control, and the power control, battery,
and battery charger, as well as the attitude control gas bottles and
the rocket engine. On top of the base was a tall pyramid-shaped mast on
which the science experiments were mounted which brought the total
height of the spacecraft to 3.66 meters. Attached to either side of the
base were rectangular solar panel wings with a total span of 5.05 meters
and width of 0.76 meters. Attached by an arm to one side of the base
and extending below the spacecraft was a large directional dish antenna.
The Mariner 2 power system consisted of the two solar cell wings, one
183 cm by 76 cm and the other 152 cm by 76 cm (with a 31 cm dacron
extension (a solar sail) to balance the solar pressure on the panels)
which powered the craft directly or recharged a 1000 Watt-hour sealed
silver-zinc cell battery, which was used before the panels were
deployed, when the panels were not illuminated by the Sun, and when
loads were heavy. A power-switching and booster regulator device
controlled the power flow. Communications consisted of a 3 Watt
transmitter capable of continuous telemetry operation, the large high
gain directional dish antenna, a cylindrical omnidirectional antenna at
the top of the instrument mast, and two command antennas, one on the end
of either solar panel, which received instructions for midcourse
maneuvers and other functions.
Propulsion for midcourse maneuvers was supplied by a monopropellant
(anhydrous hydrazine) 225 N retro-rocket. The hydrazine was ignited
using nitrogen tetroxide and aluminum oxide pellets, and thrust
direction was controlled by four jet vanes situated below the thrust
chamber. Attitude control with a 1 degree pointing error was maintained
by a system of nitrogen gas jets. The Sun and Earth were used as
references for attitude stabilization. Overall timing and control was
performed by a digital Central Computer and Sequencer. Thermal control
was achieved through the use of passive reflecting and absorbing
surfaces, thermal shields, and movable louvers.
The scientific experiments were mounted on the instrument mast and base.
A magnetometer was attached to the top of the mast below the
omnidirectional antenna. Particle detectors were mounted halfway up the
mast, along with the cosmic ray detector. A cosmic dust detector and
solar plasma spectrometer detector were attached to the top edges of the
spacecraft base. A microwave radiometer and an infrared radiometer and
the radiometer reference horns were rigidly mounted to a 48 cm diameter
parabolic radiometer antenna mounted near the bottom of the mast. All
instruments were operated throughout the cruise and encounter modes
except the radiometers, which were only used in the immediate vicinity
of Venus.
Mission Profile
After launch and termination of the Agena first burn, the Agena-Mariner
was in a 118 km altitude Earth parking orbit. The Agena second burn some
980 seconds later followed by Agena-Mariner separation injected the
Mariner 2 spacecraft into a geocentric escape hyperbola at 26 minutes 3
seconds after lift-off. Solar panel extension was completed about 44
minutes after launch. On 29 August 1962 cruise science experiments were
turned on. The midcourse maneuver was initiated at 22:49:00 UT on 4
September and completed at 2:45:25 UT 5 September. On 8 September at
17:50 UT the spacecraft suddenly lost its attitude control, which was
restored by the gyroscopes 3 minutes later. The cause was unknown but
may have been a collision with a small object. On October 31 the output
from one solar panel deteriorated abruptly, and the science cruise
instruments were turned off. A week later the panel resumed normal
function and instruments were turned back on. The panel permanently
failed on 15 November, but Mariner 2 was close enough to the Sun that
one panel could supply adequate power. On December 14 the radiometers
were turned on. Mariner 2 approached Venus from 30 degrees above the
dark side of the planet, and passed below the planet at its closest
distance of 34,773 km at 19:59:28 UT 14 December 1962. After encounter,
cruise mode resumed. Spacecraft perihelion occurred on 27 December at a
distance of 105,464,560 km. The last transmission from Mariner 2 was
received on 3 January 1963 at 07:00 UT. Mariner 2 remains in
heliocentric orbit.
Scientific Results
Scientific discoveries made by Mariner 2 included a slow retrograde
rotation rate for Venus, hot surface temperatures and high surface
pressures, a predominantly carbon dioxide atmosphere, continuous cloud
cover with a top altitude of about 60 km, and no detectable magnetic
field. It was also shown that in interplanetary space the solar wind
streams continuously and the cosmic dust density is much lower than the
near-Earth region. Improved estimates of Venus' mass and the value of
the astronomical unit were made.
Total research, development, launch, and support costs for the Mariner
series of spacecraft (Mariners 1 through 10) was approximately $554
million.
JFK Receives Mariner Model
William H. Pickering, (center)
director of NASA's Jet Propulsion Laboratory, presents a model of the
Mariner spacecraft to President John F. Kennedy in 1961. NASA
Administrator James Webb is standing directly behind the model.
Image Credit: NASA
http://exploration.grc.nasa.gov/education/rocket/gallery/atlas/atlas1.html
Mariner 2
Mariner 2 was the world's first successful
interplanetary spacecraft. Launched Aug. 27, 1962, on an Atlas-Agena
rocket, Mariner 2 passed within about 34,000 kilometers (21,000 miles)
of Venus, sending back valuable new information about interplanetary
space and the Venusian atmosphere. Mariner 2 recorded the planet's
temperature for the first time, revealing the its very hot atmosphere of
about 500 degrees Celsius (900 degrees Fahrenheit). The spacecraft's
solar wind experiment was the first to measure the density, velocity,
composition and variation over time of the solar wind.
Subsequent missions have further explored Venus, detecting electrical activity, which was confirmed by the European Space Agency's Venus Express earlier this week.
Subsequent missions have further explored Venus, detecting electrical activity, which was confirmed by the European Space Agency's Venus Express earlier this week.
Image Credit: NASA/JPL
NASA’s exploration of the solar system began 50 years ago with the
successful launch of the Mariner 2 spacecraft on Aug. 27, 1962. The
spacecraft launched aboard an Atlas-Agena rocket and passed within about
21,000 miles (34,000 kilometers) of Venus, sending back valuable new
information about interplanetary space and the Venusian atmosphere. The
mission recorded the planet's temperature for the first time, revealing
its very hot atmosphere of about 500 degrees Celsius (900 degrees
Fahrenheit). The spacecraft's solar wind experiment was the first to
measure the density, velocity, composition and variation over time of
the solar wind. The probe stopped transmitting in 1963 after delivering a
wealth of scientific information.
Since the success of Mariner 2, NASA successfully has launched a host of solar system mission, notably Cassini to study to Saturn and its moons, and multiple missions to Mars, the latest of which, Curiosity, landed on the Red Planet in August 2012.
To commemorate the 50th anniversary of this, the first successful planetary mission, the NASA History Program Office, in conjunction with the Division of Space History at the National Air and Space Museum, the NASA Science Mission Directorate and the Jet Propulsion Laboratory will host a symposium on Oct. 25-26, 2012. The event will be held at the Lockheed Martin Global Vision Center, 2121 Crystal Drive, Arlington, Va. Participation is open to the public, although registration will be required.
The Solar System Exploration @ 50 symposium will explore issues of interest to scholars, media and the public covering the 50-year history of the space age, what scientists have learned about the other bodies of the solar system and the process whereby they have learned it.
This symposium seeks to pursue broader questions relating to the history of planetary exploration, such as various flight projects and their broader implications for the exploration of other solar system bodies; development of space science disciplines and institution building; the relationships of organizations/international, civil/military, etc., one to another; as well as the relationship between robotic exploration and human spaceflight. The symposium participants also will offer analyses of the science of solar system origins and evolution.
Since the success of Mariner 2, NASA successfully has launched a host of solar system mission, notably Cassini to study to Saturn and its moons, and multiple missions to Mars, the latest of which, Curiosity, landed on the Red Planet in August 2012.
To commemorate the 50th anniversary of this, the first successful planetary mission, the NASA History Program Office, in conjunction with the Division of Space History at the National Air and Space Museum, the NASA Science Mission Directorate and the Jet Propulsion Laboratory will host a symposium on Oct. 25-26, 2012. The event will be held at the Lockheed Martin Global Vision Center, 2121 Crystal Drive, Arlington, Va. Participation is open to the public, although registration will be required.
The Solar System Exploration @ 50 symposium will explore issues of interest to scholars, media and the public covering the 50-year history of the space age, what scientists have learned about the other bodies of the solar system and the process whereby they have learned it.
This symposium seeks to pursue broader questions relating to the history of planetary exploration, such as various flight projects and their broader implications for the exploration of other solar system bodies; development of space science disciplines and institution building; the relationships of organizations/international, civil/military, etc., one to another; as well as the relationship between robotic exploration and human spaceflight. The symposium participants also will offer analyses of the science of solar system origins and evolution.
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com Incríbete en el Foro del blog y participa : A Vuelo De Un Quinde - El Foro!
No hay comentarios:
Publicar un comentario