[dorlomin]

About $200k of a Falcon 9 is fuel costs. It is as dumb to claim that energy will restrict space flight as to claim energy will restrict computing. The cost is staff, design and fabrication, you increase the rate of flight you drop the cost, even with a tripling of energy costs.

It will be a while before we colonise the solar system. But this is due to poor leadership not inherent cost barriers.

[SeaGypsy]

Actually it's to do with biology & physics. But heck, who said you can't make lots of dosh out of fantasy?

[ralfy]

$this->bbcode_second_pass_quote('dorlomin', 'A')bout $200k of a Falcon 9 is fuel costs. It is as dumb to claim that energy will restrict space flight as to claim energy will restrict computing. The cost is staff, design and fabrication, you increase the rate of flight you drop the cost, even with a tripling of energy costs.

It will be a while before we colonise the solar system. But this is due to poor leadership not inherent cost barriers.

[SeaGypsy]

If miraculously 'meeting the basic needs of humanity' became the overarching principle, we would all be in a very different situation. For one, these morons fantasies about living in space would appear as vacuous as they really are.

[dorlomin]

$this->bbcode_second_pass_quote('ralfy', '
')As it is, there is barely enough energy and material resources to meet just the basic needs of the human population.

[ralfy]

$this->bbcode_second_pass_quote('dorlomin', '')$this->bbcode_second_pass_quote('ralfy', '
')As it is, there is barely enough energy and material resources to meet just the basic needs of the human population.

[Sixstrings]

$this->bbcode_second_pass_quote('dorlomin', 'A')bout $200k of a Falcon 9 is fuel costs.

[Tanada]

Well ESA has announced Venus Express ran out of fuel mid way through the orbit raising burns in November.

$this->bbcode_second_pass_quote('', 'T')he mission then continued in a reduced science phase, as the closest
approach of the spacecraft to Venus steadily decreased again naturally
under gravity.

Under the assumption that there was some propellant still remaining, a
decision was taken to correct this natural decay with a new series of
raising manoeuvres during 23-30 November, in an attempt to prolong the
mission into 2015.

However, full contact with Venus Express was lost on 28 November. Since
then the telemetry and telecommand links had been partially re-established,
but they were very unstable and only limited information could be retrieved.

"The available information provides evidence of the spacecraft losing
attitude control most likely due to thrust problems during the raising
manoeuvres," says Patrick Martin, ESA's Venus Express mission manager.

"It seems likely, therefore, that Venus Express exhausted its remaining
propellant about half way through the planned manoeuvres last month."

Unlike cars and aircraft, spacecraft are not equipped with fuel gauges,
so the time of propellant exhaustion for any satellite - especially after
such a long time in space - is difficult to predict. The end could not
be predicted but was not completely unexpected either.

Without propellant, however, it is no longer possible to control the attitude
and orient Venus Express towards Earth to maintain communications. It
is also impossible to raise the altitude further, meaning that the spacecraft
will naturally sink deeper into the atmosphere over the coming weeks.

[Subjectivist]

Well that stinks, the artical says they have lost orientation control of the spacecraft so they only get data at intervals as it slowly tumbles in orbit. Within a few months it will enter the atmosphere and burn up.
So long Venus Express, you did your best and we are proud of what you accomplished!

[Sixstrings]

What went wrong? Why did it "run out of fuel?"

It's a reminder that these are very complex missions where anything that can go wrong will and they have to plan for every possibility, and redundancies, and even something unexpected will still go wrong.

Real space stuff gets me thinking of Kerbal Space Progam, lol. Like with Philae, I'm thinking well ok so the rock outcropping is blocking the solar panel -- they should have had an RTG on the thing! That's what I'd have done in kerbal space and I wouldn't have had that problem, I finally learned about blocked solar panels. Now I put on an RTG just in case, and plenty of batteries to cover data transmission even if all power fails.

The old Voyager probes are still amazing, how they made all their targets with gravity assists and exact timing (engineers on ground using slide rules), and did so much with those things.

[Tanada]

$this->bbcode_second_pass_quote('Sixstrings', 'W')hat went wrong? Why did it "run out of fuel?"

[Keith_McClary]

$this->bbcode_second_pass_quote('Sixstrings', 'W')hat went wrong? Why did it "run out of fuel?"

It's a reminder that these are very complex missions where anything that can go wrong will and they have to plan for every possibility, and redundancies, and even something unexpected will still go wrong.

Real space stuff gets me thinking of Kerbal Space Progam, lol. Like with Philae, I'm thinking well ok so the rock outcropping is blocking the solar panel -- they should have had an RTG on the thing! That's what I'd have done in kerbal space and I wouldn't have had that problem, I finally learned about blocked solar panels. Now I put on an RTG just in case, and plenty of batteries to cover data transmission even if all power fails.

The old Voyager probes are still amazing, how they made all their targets with gravity assists and exact timing (engineers on ground using slide rules), and did so much with those things.

[Sixstrings]

$this->bbcode_second_pass_quote('Keith_McClary', 'I') guess those backward Europeans never heard of RTGs.

[Sixstrings]

$this->bbcode_second_pass_quote('Tanada', '')$this->bbcode_second_pass_quote('Sixstrings', 'W')hat went wrong? Why did it "run out of fuel?"

[Subjectivist]

$this->bbcode_second_pass_quote('Sixstrings', '
')
I should probably join the kerbal space program forum and make a thread there (but this is my only forum), I know you guys have no idea what I'm talking about but it's just hilarious, it's a classic KSP mishap -- where you're like "doh! the rocks are the shading my solar panels, shoulda had an RTG!"

I don't know why RTGs aren't used more these days, other than mass savings.

This is a radioisotope thermoelectric generator:

$this->bbcode_second_pass_quote('', 'W')hy were solar panels used on the Philae Lander when we have RTG

[vox_mundi]

So six, where you stashing your Pu 238 ...

Pu 238 Global supply - less than 10 kg

Mars rover Curiosity utilizes 4.8 kilograms of Pu-238 borrowed from a Soviet-era nuclear weapons plant.

Cost - over $8 Million a kg

Rate of production - 1.5 kg per year

Last produced in the U.S. in 1988

There's still hope

NASA considers possibilities for manned mission to Venus
http://phys.org/news/2014-12-nasa-possi ... venus.html

[Sixstrings]

$this->bbcode_second_pass_quote('Subjectivist', 'T')he hysterical anti-nuclear crowd protests ever RTG launch and have even gone to court seeking injunctions. Eventually the probe builders got tired of it and just went solar to shut them up even though for most probes an RTG would be much more sensible.

[Sixstrings]

$this->bbcode_second_pass_quote('vox_mundi', 'h')ttp://phys.org/news/2014-12-nasa-possibilities-mission-venus.html

[Subjectivist]

A balloon filled with earth air at sea level pressure is Bouyant at the same pressure level in Venusian air. That means a probe using a balloon floats at a level where the temperature and pressure is very earth like. There have even been stories about colonists living on Venus in balloon cities floating above the clouds and using robotic equipment to mine the surface.