Free Republic
Browse · Search
News/Activism
Topics · Post Article

Skip to comments.

Scientists Plan Pluto Flyby
BBC ^ | 2-26-2002 | David Whitehouse

Posted on 02/26/2002 6:45:06 AM PST by blam

Tuesday, 26 February, 2002, 15:05 GMT

Scientists plan Pluto flyby

Golden opportunity to study Pluto

By Dr David Whitehouse
BBC News Online science editor

Many scientists are keen to plan for a Pluto encounter as the planet and its large moon, Charon, represent one of the true frontiers in the solar system that no spacecraft has ever visited.
This is despite the fact that the money for a mission to Pluto is in jeopardy as Nasa contemplates its future spending plans.

If scientists do not make plans now and be ready to act swiftly if the money becomes available, they may miss a golden opportunity to study the planet at the end of the Solar System.

They say if they do not get there soon, they may miss amazing sights that will not reoccur for almost 250 years.

Jupiter first

There are two reasons why scientists want to get there as soon as possible. The first has to do with its atmosphere.

Since 1989, Pluto has been moving farther from the Sun and as it gets colder its atmosphere will freeze out, so researchers want to arrive while there is a chance to see it.

The second reason is to map as much of Pluto and Charon as possible. The longer we wait, the more of Pluto and Charon will be shadowed for decades impeding the spacecraft's ability to take pictures in reflected sunlight.

Celestial mechanics say that an opportunity to launch to Pluto by way of Jupiter, which gives it a gravity kick, occurs in January 2006.

But given the uncertainty about the money that do not provide much time to get a probe designed and built. But if it does get off, scientists know what they want to do.

From Earth, the spacecraft will head to Jupiter, arriving just over a year later. Passing the Jovian system at 80,500 km per hour (50,000 mph) it will move on a trajectory that will arrive at Pluto and Charon as early as 2015.

The cameras on the spacecraft will start taking data on Pluto and Charon a year before it arrives and about three months from the closest approach - when Pluto and Charon are about 160,000 kilometres (100,000 miles) away - the spacecraft can make the first maps.

One day only

The busiest part of the Pluto-Charon flyby lasts a full Earth day. On the way in, the spacecraft will make the best global maps of Pluto and Charon in green, blue, red, and a special wavelength that is sensitive to methane frost on the surface.

The spacecraft will get as close as about 9,600 kilometres (6,000 miles) from Pluto and about 27,000 kilometres (17,000 miles) from Charon. During the half hour when the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The best pictures of Pluto will depict surface features as small as 60 meters (about 200 feet) across.

But even when it has sailed past Pluto the spacecrafts scientific life is far from over.

After passing Pluto it will retarget itself for an encounter with a Kuiper Belt Object (KBO) - one of the many large chunks of rock and ice that have been found in the cold outer reaches of the solar system in the past decade.

The team has not yet identified their target KBO, but scientists expect to find one or more the spacecraft can reach that are 50-100 kilometres (about 30-60 miles) across.

With so much pioneering science that such a probe could do researchers know they can make a case for the Pluto probe. They just hope that the politicians are listening.

Despite their proximity, Pluto and Charon are covered with bright frosts of differing compositions.

Water ice covers Charon, while Pluto's surface is predominantly nitrogen frost with traces of methane and carbon monoxide ices.

The Pluto/Charon system has a highly elliptical orbit around the sun. In 1989, Pluto was as close to the Sun as it gets during its long year - less than 30 astronomical units (AU), or 30 times the distance between Earth and the Sun. That distance nearly doubles just half a Pluto year later, to 50 AU in 2123.

As Pluto recedes from the Sun, much of its thin nitrogen atmosphere will condense as frost on the surface. This periodic reappearance of fresh frost takes place every Pluto year (248 Earth years) and is the reason that Pluto's is one of the most reflective surfaces in the solar system.


TOPICS: Culture/Society; News/Current Events
KEYWORDS:
Navigation: use the links below to view more comments.
first previous 1-2021-4041-42 next last
To: RightWhale

"...As a guess it is the Sitchin planet, the 12th planet,..."


Now that would be worth looking into. However, I certainly believe that it is more than 30 or 40 miles in diameter. It is most likely a "Brown Dwarf". Now you know that Sitchin already named the planet and logged it as a matter of Public record.


I believe that it is named "Marduk" in Sumerian, and called "NUDIMMUD" in Babylonian.


21 posted on 02/26/2002 11:32:28 AM PST by vannrox
[ Post Reply | Private Reply | To 19 | View Replies]

To: Cincinatus
From a news release:

"The House and Senate ultimately went against NASA and Bush administration wishes by including $30 million for the Pluto Kuiper Express mission."

Looks like it is up to Congress. I'm not an advocate of the Pluto-Kuiper Mission; Pluto is not going to be important to space exploration for a long time to come, even if now is an opportunity to explore the planet before its atmosphere freezes once again. The next opportunity will be in a couple of centuries. Pluto can wait.

22 posted on 02/26/2002 11:39:47 AM PST by RightWhale
[ Post Reply | Private Reply | To 20 | View Replies]

To: RightWhale
Yes, I know -- that was last year. The current year OMB proposed budget has the Pluto mission at ZERO. Sure, Congress can add money again, but only enough to continue the slow torture, not actually fly the mission.
23 posted on 02/26/2002 11:46:26 AM PST by Cincinatus
[ Post Reply | Private Reply | To 22 | View Replies]

To: vannrox
I hesitate to explain things that are so well known to everyone present here, but please humor me because I am a physicist, and therefore must start at the beginning.......

Uh....some of us are just dumb Joes who love this stuff.....I revel in your knowledge....even tho it will take me 3 or 4 hours to try and understand it.

24 posted on 02/26/2002 11:47:42 AM PST by Focault's Pendulum
[ Post Reply | Private Reply | To 4 | View Replies]

To: blam

Orbital Cameras




The Pluto orbiter will carry two CCD cameras for the purpose of taking detailed maps of both Pluto and Charon. The cameras will take photographs in the visible and far infrared spectra, one camera dedicated to each wavelength range. The visible light will be used to build up a map of Pluto and Charon's surfaces which, when combined with the radar altimetry information, should be extremely accurate.


The far infrared data collected will be used to construct a map of the heat flow from Pluto and Charon, which would be created by activity within the planet and moon. This information, when combined with the magnetometer information, should give us more information about the very centres of the two bodies, telling us how active they are.


The cameras are very similar to the Mars Orbital Camera used so sucessfully on the Mars Global Surveyor. It has a 35cm aperture, with a 3.5 metre focal length. It's field of view is limited to 0.4 degrees. The CCD consists of dual 2048 element line arrays, giving a maximum picture resolution of 2048x2048 pixels.


Quick Glance Specifications (Both Cameras Combined);
Experiment mass: 42.00 kg
Average experiment power: 16.00 W
Average experiment bit rate:18.24 kbps


Radar Sounder and Altimeter




The radar sounder and altimeter carried on board the orbiter will provide information on the exact shape of Pluto's surface, and should also show the structure of the ice layers beneath the surface.


The device will emit a radar pulse towards the surface of the planet as it passes overhead. The radar signal will then travel at the speed of light to the surface and be partially reflected back towards the orbiter and partially transmitted through the ice.


Because the pulse will be partially reflected and partially transmitted at every dielectric boundary, it should be reflected every time the ice changes composition - at the surface and at every boundary between layers of ice. The time delay between the pulses being received back at the orbiter will be measured. This should allow the creation of a detailed map of the sub-surface ice, possibly even rock layers, when used continuously around the globe of Pluto.


Quick Glance Specifications;
Experiment mass: 9.70 kg
Average experiment power: 18.00 W
Average experiment bit rate: 0.50 kbps


UV Spectrometer




The orbtier will carry an ultraviolet spectrometer. The main use for this instrument is to detect and determine the composition of Pluto's atmosphere. Pluto's atmosphere is seasonal; as the planet moves away from the Sun in its orbit, the temperature drops and the atmosphere is frozen into the surface of the planet as solid ices.


The atmosphere scatters the ultraviolet light is receives from the Sun. These scattered rays can be detected and their absorption patterns analysed, revealing what type of gas scattered the rays, and hence revealing the composition of the atmosphere.


The spectrometer will collect light through a 125mm Cassegrain telescope, which will direct light through a grating to the detector.


Quick Glance Specifications;
Experiment mass: 3.10 kg
Average experiment power: 1.70 W
Average experiment bit rate: 1.00 kbps


IR Spectrometer




On board the Pluto probe, there will be an IR spectrometer. The main function of this device is to spectroscopically analyse and map the surface of the planet.


Because infra red radiation is allowed to pass through the atmosphere, it is scattered by the surface of the planet. The sunlit sides of both Pluto and Charon will be mapped in infra red light, providing data that will aid in determining the composition of the surfaces of both Pluto and Charon. This may help in answering the question of whether or not Pluto and Charon are from the same source, and even if they used to be part of the same body.


It is already known that the surface of the planet is made up of ice, but we are uncertain of the composition of the ice. It is also unknown what causes the difference in darkness of some areas of Pluto's surface. It could be that there are organic type molecules such as methane locked in the ice, though this is only speculation. The IR spectrometer should be able to help determine this for certain, in addition to the data provided by the landers.


Quick Glance Specifications;
Experiment mass: 18.00 kg
Average experiment power: 12.00 W
Average experiment bit rate: 11.52 kbps


Magnetometer




On board the Pluto orbiter, there will be a magnetometer. This will measure the strength and direction of the magnetic field surrounding Pluto. A magnetic field such as this could indicate internal activity within the planet. The magnetometer that is to be used is similar to those used on the two Voyager missions and also numerous Mariner missions. It is a Triaxial Fluxgate magnetometer.


This type of instrument actually uses 2 magnetometers, a high-field and a low-field triaxial fluxgate magnetometer, thus giving a range of measurements from 0.01nT to 2mT. Two magnetometers are used so that they can be simultaneously analysed to seperate the ambient fields from the spacecraft fields.


The magnetometers will be placed on a boom extending outwards from the main body of the craft, thus keeping them away from interference produced by other instruments and ferrous materials.


Quick Glance Specifications;
Experiment mass: 5.60 kg
Average experiment power: 2.20 W
Average experiment bit rate: 0.12 kbps

25 posted on 02/26/2002 11:48:29 AM PST by vannrox
[ Post Reply | Private Reply | To 1 | View Replies]

To: vannrox
The nuclear-plasma motor is ideal for a Pluto mission. Nuclear power source, plasma or ion reaction mass.
26 posted on 02/26/2002 11:51:20 AM PST by RightWhale
[ Post Reply | Private Reply | To 4 | View Replies]

To: Cincinatus
Pluto


No one has seen the face of Pluto before Hubble's historic images.  Maps derived from Hubble data shaow that Pluto has the highest contrast between light and dark regions of any planet except Earth.

Pluto Specifications:
Year (Earth days) 60191.00
Day (Earth hours) 159h 19m
Diameter (km) 2400.00
Diameter (miles) 1500.00
Density (water = 1) 0.70
Moons 1.00
Surface Gravity (Earth = 1) 0.03
Mass (x10,000,000,000,000 Gigatons) 0.06
Distance from Sun (Million km) 5902.80
Distance from Sun (Million miles) 3667.90
Orbital Velocity (km/sec) <4.77
Orbital Velocity (miles/sec) <2.96

27 posted on 02/26/2002 12:20:47 PM PST by vannrox
[ Post Reply | Private Reply | To 23 | View Replies]

To: blam

Case Studies : Hardware Project Control


National Aeronautics and Space Administration



Parametric Method Helps NASA Make Early Cost Estimates of Pluto Mission


Huntsville, AL

BACKGROUND

The use of parametric cost estimation is helping engineers at NASA's Marshall Space Flight Center (MSFC) make early cost estimates for a proposed mission to Pluto. Cost estimates are critical in the early phases of projects in order to obtain budgetary approval and evaluate various approaches early in the life of the proposed program when they can have the most impact on its cost. MSFC uses a cost model developed by the government especially for aerospace program costs but it works at a very high level so it often isn't very useful for comparing alternative approaches at the subsystem level and below. In recent years, MSFC has supplemented these estimates with those provided by a commercial software package that offers the ability to create a model that is as detailed as desired and provides an extensive database that quickly generates system, subsystem and component cost estimates based on real-world experience. This approach proved very useful in providing early estimates of the cost of making the first flyby of the last unexplored planet as well as the Kuiper Belt, which lies beyond it and hasn't changed much since the solar system was created.

Pluto is the only planet in our Solar System not yet viewed close-up by spacecraft, and given its great distance and tiny size, study of the planet continues to challenge and extend the skills of planetary astronomers. Most of what we know about Pluto we have learned since the late 1970s. Many of the key questions about Pluto and its satellite Charon await the close-up observation of a space flight mission. Beyond Pluto lies the recently-discovered Kuiper Belt of "ice dwarfs" or minor planets. NASA originally planned to launch the Pluto-Kuiper Express in 2004 to conduct the first reconnaissance of Pluto and its large moon Charon with low mass flyby spacecraft, using advanced technologies to serve as a pathfinder for low cost exploration of the outer Solar System. The scientific goals of the mission were to 1) characterize the global geology and geomorphology of Pluto and Charon, imaging both sides of each 2) map the surface composition and 3) characterize Pluto's neutral atmosphere, including composition, thermal structure, and aerosol particles.

Need for a lower cost approach

Missions to the outer Solar System are by nature complex and expensive and it soon became clear that the funding was inadequate to launch the series of missions NASA had hoped for during the next decade. Last fall, NASA Headquarters announced that - because both the Pluto-Kuiper Express Mission and the Europa Orbiter mission to follow it were now certain to cost almost twice as much as the Jet Propulsion Laboratory had first suggested - the 2004 Pluto mission would be cancelled, to ensure that there were enough funds to launch the Europa mission in 2007. Europa is the subject of great scientific interest because of the possibility that it may hold life, but the Pluto cancellation nevertheless disappointed the planetary science community. They pointed out that if the 2004 launch opportunity is missed there can be no gravity-assist flyby of Jupiter to catapult them out to Pluto and that the Europa mission, on the other hand, could tolerate a launch delay without any loss of science. As a result, NASA Headquarters began soliciting proposals for a simpler, less expensive Pluto-Kuiper Belt mission, ideally one that could be flown for under $500 million.

As the request for proposals put it: "Every aspect of the investigation must reflect a commitment to mission success while keeping total costs as low as possible. Consequently, the investigation should be designed to emphasize mission success within the specified cost and schedule constraints by incorporating sufficient cost, schedule, and design margins, reserves, and content resiliency." MSFC with partners Teledyne Brown Engineering (TBE), Los Alamos National Laboratory (LANL), and NASA Glenn Research Center (GRC) put together a team of engineers from the disciplines involved, including structural, thermal control, propulsion, and avionics, in an effort to meet this challenge. These engineers developed rough order of magnitude subsystem level design specifications, in many cases developing multiple alternative designs. The MSFC/TBE/LANL/GRC design efforts resulted in a Pluto Orbiter which far surpassed the original specification for a flyby mission. Their work was turned over to the engineering cost group, the group that is responsible for developing cost estimates of various proposals for accomplishing this mission. NASA has used parametric costing methods for about three decades. One tool that they used on this project is the NASA/Air Force Cost Model (NAFCOM96) which is an innovative tool for developing a high level estimate of aerospace program costs.

Need to penetrate to subsystem level and below



"NAFCOM is a great tool for system level analysis," said Mahmoud Naderi, aerospace technology technical manager for MSFC. "It's designed specifically for aerospace projects and does a great job of capturing the way the government works. But it has its limitations, including the fact that it is primarily designed for use at the system level, so it doesn't capture differences in approach at the subsystem or component level very well. Also, this tool can't incorporate the effects of risk on a project, such as the possibility that a certain subsystem may end up costing considerably more than we originally estimated. For these reasons, and because we like to compare the results of multiple tools, we have begun using commercial software packages to provide complementary cost estimates. One of the commercial tools that we use most is SEER-H&#8482; from Galorath Incorporated (www.galorath.com), which penetrates to the subsystem level and below, while allowing us to analyze alternatives and risk factors at any level that we choose. It has the rich feature set that you would expect from a leading commercial package, including the ability to capture virtually any technical detail you can think of and include it in the analysis."

SEER-H has approximately 40 knowledge bases for electronic elements and for mechanical. While SEER-H is primarily focused on the development process, it also includes manufacturing cost estimation capabilities for low volume production. The program is sensitive to the difference between mechanical and electrical elements and between labor and materials costs. It also bases the price of individual PCBs on their number of components rather than their weight, an approach that usually provides more realistic results. SEER-H allows the user to choose the probability level of estimates, and set different levels for each portion of the project. It also provides detailed sensitivity analysis features that make it possible to determine the impact of adjusting specific project factors. This feature, for instance, makes it possible to quickly estimate the impact on cost if a project schedule is compressed by two months. This software package reduces the learning curve by avoiding the use of less-than-obvious adjustments in order to present the estimating objective more clearly.

Generating the parametric model



Charles Hunt, industrial engineer for NASA, performed the analysis of several proposals on the new proposed Pluto-Kuiper Belt mission. "The project manager provided me with the general technical specifications and a weight statement," Hunt said. "I transposed the information into SEER parameters and began entering high level systems data into the software package. The process of compiling and entering the information and generating the initial model took only two hours. Then I had a completed cost model that I was able to take back to the program manager and other members of the engineering team for their feedback. In many cases, when they saw the output of the model, it prompted them to adjust their original specifications to make them more realistic. Engineers frequently provided me with alternatives and I was able to quickly use the parametric approach to provide near real-time feedback on development and manufacturing costs of each approach. As a result, we moved through many iterations at a rapid pace, continually improving the accuracy of the model. As detailed information is developed by the engineering team, we will capture that in the program. SEER-H will search through its database for similar assemblies and then use the experience gained from earlier programs to improve the accuracy of the model. I will stay involved with the project and continually update the model to reflect the latest thinking of the design team."
With SEER-H and other tools, Hunt is in the process of providing the project team with a realistic, well-documented budget that they can take to Congress to ask for funding. The capability of the program to quickly evaluate the cost of alternate approaches is saving considerable time during the proposal process by providing information that guides engineers toward a cost effective approach sooner than it would have otherwise been available. If the Pluto-Kuiper Belt program is approved, the SEER model will be developed to a finer level of detail and used to make subassembly and component decisions and to determine the effect of specification and scheduling changes on costs. "SEER, in combination with other tools, provides a time-efficient and accurate method for generating cost estimates," Naderi concluded.


28 posted on 02/26/2002 12:38:36 PM PST by vannrox
[ Post Reply | Private Reply | To 1 | View Replies]

To: RightWhale;Calvin Locke
"As a guess it is the Sitchin planet, the 12th planet, which some people think --for whatever reason-- is on its way to earth once again. "

Along the same line are those that believe our sun has a companion star, Death Star, that drops by every few thousand years and disrupts the oort cloud and sends asteroids crashing into earth.

29 posted on 02/26/2002 1:09:34 PM PST by blam
[ Post Reply | Private Reply | To 19 | View Replies]

To: blam
...oort cloud and sends asteroids crashing into earth

I thought that's where comets are spawned.

30 posted on 02/26/2002 1:15:26 PM PST by Calvin Locke
[ Post Reply | Private Reply | To 29 | View Replies]

To: RightWhale
Why? Anything "local", with the planets in alignment, can't they just use gravity to whip that sucker around the solar system?

I though JPL was pretty good at that type of driving...

31 posted on 02/26/2002 1:20:57 PM PST by Calvin Locke
[ Post Reply | Private Reply | To 26 | View Replies]

To: Calvin Locke
comets

From what we know about asteroids and comets, what would be the difference except that comets have a greater percentage of volatiles for a while and wild orbits?

32 posted on 02/26/2002 1:26:10 PM PST by RightWhale
[ Post Reply | Private Reply | To 30 | View Replies]

To: Calvin Locke
Even with gravity asist it still takes a long time to get as far out as Pluto. A nuke-plasma motor would cut that to a couple years.
33 posted on 02/26/2002 1:28:18 PM PST by RightWhale
[ Post Reply | Private Reply | To 31 | View Replies]

To: Calvin Locke
"I thought that's where comets are spawned."

Oops! You are correct. I was referring to the asteroid belt between Mars and Jupiter. (Jeez...I have a 2fx3f picture of the whole system here above my desk) Hmmmm.

34 posted on 02/26/2002 1:36:50 PM PST by blam
[ Post Reply | Private Reply | To 30 | View Replies]

To: RightWhale
...would be the difference ...

You can generally see comets coming for a couple of years. You never know when an asteroid is going to get ponged out
of the belt, let alone see it, track it, whatever.

Its my favorite for resetting the progress of humanity on the planet, but I don't lose any sleep over it.

35 posted on 02/26/2002 2:43:48 PM PST by Calvin Locke
[ Post Reply | Private Reply | To 32 | View Replies]

To: RightWhale
A nuke-plasma motor...

Geez, you're quite the masochist. The envirowhackos complain about the internal combustion engine.

Mention "nuke" and all bets are off.

36 posted on 02/26/2002 2:54:34 PM PST by Calvin Locke
[ Post Reply | Private Reply | To 33 | View Replies]

To: Calvin Locke
see it, track it

Here's how they spot incoming asteroids:


The Sky Is Falling? No Sweat

The process of discovering one of these rocks is akin to looking for a very tiny needle in a stadium-sized haystack that -- just to keep things interesting -- is very far away. Every night, Pravdo and his team aim their powerful electronic cameras at a small patch of the sky. They take three different pictures of the same spot, each one at a different time.

Then the three images are overlaid over each other, and the team uses a computer to see whether any of the objects appear to have moved over time. These moving objects are possible asteroids.



37 posted on 02/26/2002 3:02:20 PM PST by RightWhale
[ Post Reply | Private Reply | To 35 | View Replies]

To: blam
Hey, Blam. Any chance we can get those scientist to take some politicians with them when they fly by Pluto?
38 posted on 02/26/2002 3:03:29 PM PST by DugwayDuke
[ Post Reply | Private Reply | To 1 | View Replies]

To: Calvin Locke
The Bush Administration is pushing to develop nuke-plasma motor technology. It could happen. Greenies will have a field day, but it won't matter.
39 posted on 02/26/2002 3:04:23 PM PST by RightWhale
[ Post Reply | Private Reply | To 36 | View Replies]

To: Paradox
LOL! Good work! I was looking for a picture of the "real" Pluto myself, but I see you beat me to it.

I wonder if scientists will plan a Goofy flyby?

40 posted on 02/26/2002 3:07:23 PM PST by Jay W
[ Post Reply | Private Reply | To 10 | View Replies]


Navigation: use the links below to view more comments.
first previous 1-2021-4041-42 next last

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
News/Activism
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson