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Posted by baalke on August 30, 2007, 2:16 pm
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http://www.jpl.nasa.gov/news/features.cfm?feature=1448
Up, Up and Away -- To Venus
Jet Propulsion Laboratory
August 27, 2007
Scientists hope to learn more about climate changes here on Earth by
studying Venus. A prototype balloon could eventually study the planets
surface and examine its atmosphere and the bizarre winds and chemistry
within it. A team of JPL, ILC Dover and NASA Wallops Flight Facility
engineers designed, fabricated and tested the balloon.
Slightly smaller than Earth, Venus is often regarded as Earth's sister
planet. Both have similar densities, chemical compositions and
gravities. However, its atmosphere is nearly 100 times thicker than
Earth's, which causes blazing temperatures at the surface. By flying
in
the cool skies above Venus, the balloons would avoid that environment.
"The surface is hot enough to melt lead, which is why we can't study
it
for long from a lander," said Kevin Baines, JPL principal investigator
for a proposed mission to Venus. "Without extreme and costly
refrigeration methods, a lander would cook at those temperatures in
just
a few hours, but a balloon can stay in a benign environment, studying
the planet for days, weeks or even months."
The spherical balloon, 18 feet in diameter, is about the size of an
inflatable children's jumper. Its aluminum coating reflects sunlight
to
protect the balloon from becoming too hot as it flies in Venus upper
atmosphere. Its outer transparent layer of the balloon is made of
polytetrafluorethylene, also known as Teflon, the non-stick material
found in cookware and on clothing. The material is highly resistant to
the sulfuric acid found in clouds surrounding Venus. The sun shines
through the Teflon and reflects off the aluminum, and that keeps the
balloon from overheating, said Jeff Hall, JPL's lead balloon engineer.
The balloon's second layer has a mylar film similar to those shiny
helium balloons found in a grocery store. The mylar is used to prevent
gas from leaking out. The next layer is made of a Vectran fabric that
provides the strength to keep the balloon from bursting due to
internal
pressure. The innermost layer has a polyurethane coating that enables
all sections of the balloon to be glued together.
More details about the design, fabrication and testing of the balloon
are reported in a paper published in the journal Advances in Space
Research..
The proposed mission would have two balloons, one at a tropical
latitude, the other at a polar latitude. Each helium-filled balloon
would fly about 56 kilometers (about 35 miles) above Venus' oven-hot
surface, in temperatures about the same as a spring afternoon in Los
Angeles. It would take about four days for the helium superpressure
balloons to fly completely around the planet. After the balloons are
launched from Earth, they would arrive on the night side of Venus.
"The winds at that altitude are very strong, more than 320 kilometers
per hour (about 200 miles an hour), and will blow the balloons around
the planet," Hall said. "Engineers would not have control of where the
balloons travel. Once the balloon starts flying, it is totally
dependent
on the winds."
Each balloon would have quite a roller coaster ride, moving up and
down
about a half a mile in altitude as they ride gravity waves generated
by
Venus mountainous terrain.
"This was one of the surprises of the Vega balloon mission the Soviet
Union flew more than two decades ago," Baines said. "Enormous gravity
waves appear to rise up more than 30 miles into the upper atmosphere,
causing unexpected depositions of energy generated at the surface and
producing strong vertical movements of air. We want to ride these
waves,
measuring their effect on Venus' bizarre high-speed winds."
Scientists believe the Venus balloons could also help us learn more
about climate changes here on Earth. Venus is a place where global
warming has gone amuck, Hall said. Its about the same size as our
planet, but the surface is about 900 degrees Fahrenheit, and we want
to
find out why.
Scientific instruments aboard the balloons would analyze the
composition
of Venus' atmosphere. The pressure cooker atmosphere around Venus
quickly changes and is filled with specific gases, such as helium and
neon, which do not interact chemically with other materials, allowing
researchers to trace the formation of Venus over time. Noble gases can
help scientists determine the geological history of the planet, which
could lead to answers about current climate changes.
"Those gases will tell us if Venus and Earth were twin planets.
Indications from previous missions suggest that Venus and Earth were
quite similar at the beginning," Baines said.
Various studies indicate Venus once had oceans of water much like
those
on Earth, but now the planet is dry. According to Baines, Venus began
as
an oasis with conditions favorable for life in its first billion
years.
"Venus now has an extreme climate. It changed from being wet and wild,
to dry and dead, and it seems to have happened in the last three
billion
years. We'd like to find out how this global transformation happened."
The current explanation for the dry atmosphere and extremely hot
surface
temperature is that Venus does not have a magnetic field to provide
protection from solar winds. Those winds smash into the top of the
atmosphere and drag off hydrogen that is needed for water.
A payload weighing more than 40 kilograms (about 90 pounds) would fly
with each balloon to help transmit data back to Earth. Included in
this
payload would be a flight computer, radio transmitter and 9 kilograms
(20 pounds) of electric batteries to power the equipment. Also
included
is a suite of science instruments:
o A gas chromatograph mass spectrometer to measure the amounts of
gases
on Venus and to sniff for volcanic smoke.
o An atmospheric structure instrument would measure the pressures and
temperatures of the atmosphere and the vertical winds as the balloons
bob up and down. This instrument also includes a nephelometer
instrument
to measure the size and density of cloud particles through light
reflections.
o A lightning detector to measure the power and frequency of nearby
lightning strikes in the atmosphere.
o A microphone to record any nearby sounds in the atmosphere,
including
thunder.
Ground-based radio telescopes using an interferometric technique would
be used to measure how each balloon moves around the atmosphere. "We'd
be able to tell its velocity within one inch per second of movement
over
an hour," Baines said. The telescopes would also use the Doppler
effect
to complete a set of 3-D measurements of each balloon's movements.
The company that built the airbags for the Mars Exploration Rover
mission, ILC Dover, Frederica, Del., also helped design and build the
balloons. The balloons are folded into small packages to fit inside
the
launch rocket that also include high pressure helium tanks and valves.
Once the balloons reach the planet, the heavy tanks would drop away so
the balloon could float away.
The balloon mission would likely end one of two ways: it might run out
of battery power, when the balloons would be unable to communicate
with
ground controllers, or if a balloon develops a leak, it would
eventually
lose altitude and overheat the payload until it stops working. Hall
and
his team of engineers in JPLs Aerobot laboratory have tested the
prototype and determined it can float for up to 12 days without
leaking
any helium gas. A 12-day flight would be long enough to allow the
balloons to circumnavigate the planet three times.
------------------------------------------------------------------------
Media contact: DC Agle/JPL
818-393-9011
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Posted by BradGuth on August 31, 2007, 12:15 am
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What a pathetic old joke, with our NASA in full infomercial media
damage-control, once again pretending at their doing a Venus mission
with old file copy none the less.
Up, Up and Away -- To Venus (on the cheap)
http://www.nasa.gov/vision/universe/solarsystem/venus-20070827.html
http://www.nasa.gov/images/content/187970main_balloon-8-27-07-browse.jpg
"This was one of the surprises of the Vega balloon mission the Soviet
Union flew more than two decades ago," Baines said. "Enormous gravity
waves appear to rise up more than 30 miles into the upper atmosphere,
causing unexpected depositions of energy generated at the surface and
producing strong vertical movements of air. We want to ride these
waves, measuring their effect on Venus' bizarre high-speed winds."
"Enormous gravity waves" ???
http://en.wikipedia.org/wiki/Gravity_wave
"In fluid dynamics, gravity waves are waves generated in a fluid
medium or at the interface between two mediums (e.g. the atmosphere or
ocean) which has the restoring force of gravity or buoyancy."
But otherwise, no kidding folks, because of all the CO2 as saturated
with S8 that's so much hotter near that grothermally active surface,
is clearly why there's such a terrific vertical velocity, as well as
downright nifty buoyancy to that robust atmosphere.
- Brad Guth
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Posted by BradGuth on August 31, 2007, 1:24 pm
Please log in for more thread options Good grief, what another pathetic infomercial spewed old joke, with
our warm and fuzzy NASA in full infomercial media damage-control, once
again via science hype diverting us away from the truth by simply
pretending at their doing such a minimal Venus mission, and with such
old file copy tactics none the less. However, unlike our moon, at
least Venus is technically doable from the toasty surface on up into
those icy cool though acidic nighttime clouds.
Up, Up and Away -- To Venus (aka: on the dirt cheap)
http://www.nasa.gov/vision/universe/solarsystem/venus-20070827.html
http://www.nasa.gov/images/content/187970main_balloon-8-27-07-browse.jpg
"This was one of the surprises of the Vega balloon mission the Soviet
Union flew more than two decades ago," Baines said. "Enormous gravity
waves appear to rise up more than 30 miles into the upper atmosphere,
causing unexpected depositions of energy generated at the surface and
producing strong vertical movements of air. We want to ride these
waves, measuring their effect on Venus' bizarre high-speed winds."
"Enormous gravity waves" ???
http://en.wikipedia.org/wiki/Gravity_wave
"In fluid dynamics, gravity waves are waves generated in a fluid
medium or at the interface between two mediums (e.g. the atmosphere or
ocean) which has the restoring force of gravity or buoyancy."
But otherwise, there's no kidding folks, because of the newish
planetology with all that CO2 as saturated with S8, being so much
hotter near that grothermally active surface, is clearly why there's
such a terrific vertical thermal differential and subsequent velocity,
as well as downright nifty buoyancy to that robust atmosphere.
Instead of going with that silly balloon, a composite rigid airship
would be far better and longer lasting, as well as capable of cruising
extensively to within a few km of that toasty deck.
"It's about the same size as our planet, but the surface is about 900
degrees Fahrenheit, and we want to find out why."
Much like good old proto-Earth, in places it's clearly much hotter
than in other places.
(think: newish planetology)
(think: much less old than Earth)
Think outside the mainstream status quo box, because there's
sufficient proof of intelligent other life existing/coexisting on
Venus. There's also insufficient proof that either Venus or Earth fit
within the popular mold of our solar system, and quite possibly either
of us were not originally associated within this solar system because,
it's becoming better understood that rogue planets do exist,
especially those of good volume and mass as having Earth like moons
that survived the demise of their original sun.
BTW, the extremely mountainous terrain of Venus suggest that it once
upon a time had a fairly substantial moon, perhaps exactly like that
moon of ours, as perhaps being the primary reason as to why Venus
remained so extra geothermal from the inside out. These days, Venus
is cooling off at roughly 20.5 w/m2 (in spite of that insulative
atmosphere, it's losing an impressive 256 fold greater thermal energy
than what Earth is losing).
http://ees.elsevier.com/jasr/
"Advances in Space Research is the Official Journal of the Committee
on Space Research (COSPAR), a Scientific Committee of the
International Council of Scientific Unions (ICSU)" is nothing but
another insider journal dump, of self promoting e-published hype at
taxpayers expense, on just about anything you'd care to find. Peer
reviewed, my ass, as only that which doesn't rock thy good ship
LOLLIPOP is allowed to stick. Their peer review simply means
revisionism of any kind is forbidden, and nothing gets interconnected,
meaning that each research topic has to be a *stand alone* or all
inclusive item without ties or links to other research (aka: no dot
connecting allowed).
- Brad Guth
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