Scientists Plan Pluto Flyby

BBC ^ | 2-26-2002 | David Whitehouse

[blam]

FYI.

[farmfriend]

When I was done reading this, I was going to call you. Then I saw you had posted it. Oh well, ping anyway.

[vannrox]

Notes:

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.
The rocket equation, derived from the requirement that the change in the total momentum must be zero, demonstrates that the change in velocity of the rocket is the product of the exhaust velocity times the logarithm of the final to initial mass. The exhaust velocity is traditionally given in terms of specific impulse (Isp) times the acceleration of gravity. Rating the various types of rockets that have been invented by their specific impulse tells us how “efficient” the rocket uses its fuel supply. On this basis, photons or light provide the most efficient use of fuel, because they travel at the maximum exhaust velocity permitted by physics—the speed of light. (If the rocket doesn’t carry its own fuel, say, by reflecting photons from the Sun, then some would say that the Isp is infinite.) From this brief survey it is apparent that photon propulsion is the best we can do. The importance of Isp is shown by the next slide.

[vannrox]

Notes:

NASA has stated that it would like to travel to the last planet remaining unvisited. It took Voyager around 16 years to make it to the orbit of Pluto, though Pluto missed the appointment. Now, 24 years later, it would seem that we should be able to arrive at Pluto much faster, so I have arbitrarily selected a 10x faster trip, or 1.6 years. Well it is easy enough to calculate the speed needed, we take the (average) orbital distance to Pluto, and divide by the number of seconds in 1.6 years, to get an average speed of about 100 km/s. This is the change in velocity needed in the rocket equation. Then selecting various specific impulses, Isp, we find that the ratio of the mass of the rocket to the mass of the payload is as given in the table. Note that a “good” Isp of around 10,000, permits a reasonably sized payload to make it to Pluto in 1.6 years. I’m glossing over another problem, of course, that high Isp rockets are generally energy starved, and would need a small nuclear reactor to provide the power for the thrust. But since everything to date has been launched by chemical rockeds, and even advanced chemical fuels will not exceed 400s of Isp, it should be clear that if we are in a hurry, we can’t get anything to Pluto much larger than a pencil eraser.

[vannrox]

Go HERE to find out more...

[vannrox]

Pluto-Kuiper Express

... to explore Pluto/Charon and the fringes of our Solar System

2000/09/13 - A NASA stop work order was issued for the Pluto-Kuiper Express mission. Further direction from NASA had been given to develop a new mission to reach Pluto before 2020.


The new mission to explore the last planet in our Solar System has been selected. Called New Horizons, this mission will be managed by Johns Hopkins University, Applied Physics Laboratory.

[Cincinatus]

Yes, that's why they want to use the Jupiter gravity-assist to get oout to Pluto. That's also why the urgency to launch by 2006.

Unfortunately, this mission was "sold" in the current budget as a pork-a-tron add-on by Sen. Barbara Mikulski (D-MD) as a way to funnel money to Johns Hopkins-APL in Maryland. This side-stepped OMB and the White House, something they generally tend to frown on -- the OMB guy who got particularly shafted in this transaction is one Sean O'Keefe. That name familiar? He's the current NASA Administrator.

Good luck on getting funding for PFF in this year's budget. The current OMB doesn't even include it.

[<1/1,000,000th%]

Nice presentation.

[Paradox]

All that to study Pluto? Whats the big deal? Why waste all that money, and why all the expensive rocketry?

[RightWhale]

If scientists do not make plans now and be ready to act swiftly if the money becomes available

Project engineers and scientists are going full-bore ahead. The funding is in the federal budget. Pretty much a done deal.

[Willie Green]

Project engineers and scientists are going full-bore ahead. The funding is in the federal budget. Pretty much a done deal.

Does the design include wheels in case of unforseen circumstances?

[Contra]

It'll never fly.

[RightWhale]

Does the design include wheels

Wheels are used to save an entire year off transit time to Pluto. They will further save money by using green neon skateboard wheels.

[Revelation 911]

Rather Pluto than - Ur-anus ;)

[RightWhale]

Whats the big deal?

They want to see what is there, like prospecting for gold. Pluto may be rich in materials useful to support space colonies; sometime down the road it could serve as a stepping stone to outer solar system development. And it is a small planet which would be easy to develop, unlike the giant gas planets.

Aside from that, I think it can wait.

[Calvin Locke]

Send a buck. Send the Gore-Sat that's mothballed.

I want to know about this dark planet that Art Bell's recent guests/callers keep talking about.

[Calvin Locke]

Make that "Save a buck"

[RightWhale]

dark planet

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. Our masters making a swing past the colony to see how their creation is doing.

[Cincinatus]

The funding is in the federal budget. Pretty much a done deal.

The only "done deal" is $ 30M in the current year budget. There is NO request for additional money in FY 03 from the administration. $ 30 M sounds like a lot, but it's about 1/20th the amount needed to fly this thing. Congress may try to add money, but it'll take at least $150 M in '03 to get the project where it ought to be; that's not an easy "add-on" for pork. It's likely that this thing is finished.