A solar-powered Jupiter mission debacle in the making?

I can't believe they did this.

(CNN) -- NASA scientists are slightly more than a week away from
launching a Jupiter mission they say will unlock key secrets of how
our solar system was formed.

After almost a decade of building and testing the Mission Juno
satellite -- a $1.1 billion spacecraft -- NASA officials placed the
craft atop an Atlas V rocket Wednesday. It is set to blast off from
Cape Canaveral, Florida, on August 5.

Juno will be launched into space atop an Atlas V 551 rocket, one of
the world's most powerful, NASA said.

Mission Juno will offer unprecedented insight into the formation of
our solar system by investigating what lies underneath Jupiter's
atmosphere, astronomers said at Kennedy Space Center. Jupiter is known
for its violent storms and gaseous atmosphere.

Scott Bolton, principal investigator for the mission, said Jupiter --
which is 1,300 times larger than Earth -- holds a key to understanding
the solar system because it's believed to be the first planet to have
formed after the sun.

"It got the majority of the leftovers after the sun formed," Bolton
said. "We want the ingredient list."

He added that the mission will investigate, among other things, what
lies in Jupiter's core.

After circling the inner ring of the solar system for two years, the
craft will use the Earth's gravitational pull to sling itself toward
the gaseous planet. By 2016, Juno will have traveled the 400 million
miles to Jupiter, according to the mission's website.

Juno's three solar arrays -- each the size of a tractor-trailer -- are
lined with solar panels that power the spacecraft, Project Manager Jan
Chodas said.

The spacecraft will be the first solar-powered satellite to journey as
far as Jupiter, Bolton said. Other NASA missions to Jupiter, like
Galileo, have used nuclear fuel.

The craft will periodically communicate with NASA engineers on Earth
and is programmed to respond to glitches and unexpected trouble, the
space site said.

NASA officials said Mission Juno will build upon knowledge gained from
previous missions to Jupiter.

Juno will be followed by other deep-space missions, NASA said.

Juno Mission Overview
http://juno.wisc.edu/mission.html

Key things to know about Juno

Spacecraft scheduled to launch between Aug. 5 and Aug. 26, 2011

Five-year cruise to Jupiter, arriving July 2016

Spacecraft will orbit Jupiter for about one year (33 orbits)

Mission ends with de-orbit into Jupiter

Juno will improve our understanding of our solar system’s beginnings by revealing the origin and evolution of Jupiter.

Specifically, Juno will…

Determine how much water is in Jupiter’s atmosphere, which helps determine which planet formation theory is correct (or if new theories are needed)

Look deep into Jupiter’s atmosphere to measure composition, temperature, cloud motions and other properties

Map Jupiter’s magnetic and gravity fields, revealing the planet’s deep structure

Explore and study Jupiter’s magnetosphere near the planet’s poles, especially the auroras – Jupiter’s northern and southern lights – providing new insights about how the planet’s enormous magnetic force field affects its atmosphere.

On Thu, 28 Jul 2011 04:00:51 -0700 (PDT), Rich
wrote, in part:

I can't believe they did this.

Why not? Unlike the surface of Mars, there are no dust storms in
interplanetary space. Solar panels will be a highly reliable source of
power.

Rockets - especially those that aren't man-rated - do occasionally blow
up on the pad. RTGs are well-shielded, of course, and I agree that the
public panic is largely unfounded, but using them _only_ when it is
essential to the mission keeps confrontations and problems to a minimum.

Of course, solar panels "the size of a tractor-trailer" are heavier than
even a well-shielded RTG, I would think, so it is unfortunate. But only
to a very limited extent.

John Savard
http://www.quadibloc.com/index.html

lid (John Savard) wrote in
:

On Thu, 28 Jul 2011 04:00:51 -0700 (PDT), Rich
wrote, in part:

I can't believe they did this.

Why not? Unlike the surface of Mars, there are no dust storms in
interplanetary space. Solar panels will be a highly reliable source of
power.

Rockets - especially those that aren't man-rated - do occasionally blow
up on the pad. RTGs are well-shielded, of course, and I agree that the
public panic is largely unfounded, but using them _only_ when it is
essential to the mission keeps confrontations and problems to a
minimum.

Of course, solar panels "the size of a tractor-trailer" are heavier
than
even a well-shielded RTG, I would think, so it is unfortunate. But only
to a very limited extent.

John Savard
http://www.quadibloc.com/index.html


It's a huge risk putting a billion dollar mission up with solar panels
than if. If they don't function, the thing is dead. The plutonium power
packs are far better. Self-contained, small, relatively light and so
simple it almost cannot fail.

The plutonium power
packs are far better. Self-contained, small, relatively light and so
simple it almost cannot fail.

You must have one up your ass ?

On Thu, 28 Jul 2011 22:30:59 -0500, Rich wrote, in
part:

Self-contained, small, relatively light and so
simple it almost cannot fail.

The first two, I'll agree with. The third, I don't know - shielding and
containment is heavy. The fourth - it is true that solar panels have
moving parts, in order to spread out, but otherwise, I would say that
both systems have that advantage.

John Savard
http://www.quadibloc.com/index.html

"Rich" wrote:

It's a huge risk putting a billion dollar mission up with solar panels
than if. If they don't function, the thing is dead. The plutonium power
packs are far better. Self-contained, small, relatively light and so
simple it almost cannot fail.

Indeed, they evaluated RTGs but quickly realized they could not afford them.
Same goes for MER: if you can build 2 rovers for $800M (including launch
vehicle) with RTGs, JPL has a job for you...

In article ,
Rich wrote:
It's a huge risk putting a billion dollar mission up with solar panels
than if. If they don't function, the thing is dead.

You test them on the ground; making sure that solar panels don't fail
to unfold while in orbit has been quite a large goal of the commercial
satellite industry for quite a long time. Satellites are still lost
for solar panel failure, but rarely (substantially more rarely than
being deposited into the Atlantic by the launch vehicle)

The plutonium power packs are far better. Self-contained, small,
relatively light and so simple it almost cannot fail.

And unaffordably costly. Except for the Stirling RTGs which have
moving parts and haven't yet been tried on orbit.

Tom

"meow" uble.cat wrote in
message ...
|
| "Rich" wrote:
|
| It's a huge risk putting a billion dollar mission up with solar panels
| than if. If they don't function, the thing is dead. The plutonium
power
| packs are far better. Self-contained, small, relatively light and so
| simple it almost cannot fail.
|
| Indeed, they evaluated RTGs but quickly realized they could not afford
them.
| Same goes for MER: if you can build 2 rovers for $800M (including launch
| vehicle) with RTGs, JPL has a job for you...
|
That's a very silly claim. I can do it for much less but...
the American people don't me to.
Why could I do it for less? Because I'm commercially driven and JPL
is part of NASA, a bureaucracy bound by laws that an international
group isn't. JPL won't give me the job because I won't use an American
launch vehicle with an American payload. Americans HATE competition
and hate to be beaten. When Britain and France built Concorde the yanks
did everything they could to scuttle the best plane ever to fly. Then
they built a fleet of the worst launch vehicle imaginable, the shuttle.
The Russian Soyuz is still going strong.
Competition between GM, Ford and Chrysler is "healthy", they all pay
US taxes. Competition between GM and non-US car builders is bad,
Japanese and Chinese don't pay US taxes. Now the US is going broke,
can't pay its debts. Who do you think you owe the money to?
Dubai has some very impressive buildings... and all you did with all
that oil you bought is burn it. The East is getting very wealthy these
days.
No son, JPL isn't offering the contract to anyone. I can get a Chinese,
Japanese, Russian, Indian or French launch vehicle for less but I
want payment up front, in gold, the USA has already lost its credit
rating.

On Jul 29, 2:57*pm, Andrex whispered treasonable thoughts about our
greatest ally:

No son, JPL isn't offering the contract to anyone. I can get a Chinese,
Japanese, Russian, Indian or French launch vehicle for less but I
want payment up front, in gold, the USA has already lost its credit
rating.

Perhaps y'all should get that nice Miss Failing to ask her North
Koreans allies to heft it up thar for y'all? You could offer more food
for the Sumo family's millions of starving conscripts. Instead of
feeding your own poor. Just ask the Tea Party. They say there's more
than enough rich cake to go around at their parties.

The only thing missing from the Amewican dream for 40% of Amewicans is
a weal Wobin Hood.

http://en.wikipedia.org/wiki/Poverty..._United_States

If there is no Robin Hood ya'll just have to invent one!

http://www.bbc.co.uk/news/world-us-canada-14296682

http://www.bbc.co.uk/news/world-us-canada-14327425

http://www.bbc.co.uk/news/world-us-canada-14327423

http://www.bbc.co.uk/news/world-us-canada-14327421

http://www.bbc.co.uk/news/world-us-canada-13358745