Phobos and Jupiter Conjunction in 3 D and Amazing Animation – Blastoff to Martian Moon near

Video Caption: Phobos and Jupiter in Conjunction – taken from Mars orbit !
A movie of the 1 June 2011 Phobos–Jupiter conjunction made by combining a sequence of 100 images of the encounter taken by the High Resolution Stereo Camera on ESA’s Mars Express orbiter. Mars Express is searching for safe landing zones on Phobos for Russia’s Phobos-Grunt lander blasting off on November 9. Credits: ESA/DLR/FU Berlin (G. Neukum)
3 D images of Phobos-Jupiter conjuction below
Update – Phobos-Grunt launch processing photo below

In just 7 days, Russia’s Phobos-Grunt sample return mission will blast off for Mars on November 9 on a daring mission to grab soil samples from the surface of the miniscule martian moon Phobos and return them back to Earth for analysis to give us breathtaking new insights into the formation and evolution of Mars, Phobos and our Solar System.

So, check out the amazing animation and 3 D stereo images of fish-like Phobos and banded Jupiter snapped by Europe’s Mars Express orbiter to get a bird’s eye feel for the battered terrain, inherent risks and outright beauty that’s in store for the Phobos -Grunt spaceship when it arrives in the Red Planet’s vicinity around October 2012. Whip out your red-cyan 3 D glasses – Now !

[/caption]

ESA’s Mars Express orbiter (MEX) was tasked to help Russia locate suitable and safe landing sites on Phobos’ pockmarked terrain. MEX was built by ESA, the European Space Agency and has been in Mars orbit since 2003.

To capture this impressive series of rare photos of Jupiter and Phobos in conjunction, Mars Express performed a special maneuver to observe an unusual alignment of Jupiter and Phobos on 1 June 2011.

Mars Express High Resolution Stereo Camera (HRSC) snapped a total of 104 images over 68 seconds when the distance from the spacecraft to Phobos was 11,389 km and the distance to Jupiter was 529 million km.

Phobos- Jupiter Conjunction: before, during and after on 1 June 2011 from Mars Express. Credits: ESA/DLR/FU Berlin (G. Neukum)

Enjoy the exquisite views of the bands of Jupiter and imagine exploring the deep pockets and mysterious grooves on Phobos – which may be a captured asteroid.

The camera was kept fixed on Jupiter, to ensure it remained static as Phobos passed in front and which afforded an improvement in our knowledge of the orbital position of Phobos.

Phobos in 3 D during flyby of 10 March 2010. Image taken from a distance of 278 km. Russia’s Phobos-Grunt will retrieve rogolith and rock for return to Earth. Credit: ESA/DLR/FU Berlin (G. Neukum)

NASA’s twin Mars rovers Spirit and Opportunity have also occasionally photographed both of Mars’ moons to further refine their orbital parameters.

NASA’s Curiosity rover remains on track to liftoff for Mars on Nov. 25

Orbital Paths of Phobos and Mars Express. The trajectories of Phobos and Mars Express at the time of the conjunction with Jupiter on 1 June 2011. The letter ‘S’ denotes the South Pole of Mars.
Technicians at Baikonur Cosmodrome prepare Phobos-Grunt for upper stage attachment. Credit: Roscosmos

Read Ken’s continuing features about Phobos-Grunt here:
Russia Fuels Phobos-Grunt and sets Mars Launch for November 9
Phobos-Grunt and Yinghou-1 Arrive at Baikonur Launch Site to tight Mars Deadline
Phobos-Grunt: The Mission Poster
Daring Russian Sample Return mission to Martian Moon Phobos aims for November Liftoff

First Image Captured by NASAs Jupiter bound Juno; Earth – Moon Portrait

[/caption]

NASA’s solar powered Jupiter bound Juno orbiter has captured her first image – a beautiful portrait of the Earth & Moon – since the probe blasted off from the home planet.

Juno lifted off 25 days ago at 12: 25 p.m. on August 5 from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The spacecraft snapped the portrait with the onboard JunoCam camera on August 26 after journeying some 6 million miles (9.66 million km) from Earth and while traveling at a velocity of 77,600 miles per hour (124,900 kilometers per hour) relative to the sun.

“The image of the Earth Moon system is a rather unique perspective that we can get only by stepping outside of our home planet,” said Scott Bolton, Juno principal investigator, in an exclusive interview with Universe Today. Bolton is from the Southwest Research Institute in San Antonio.

“On our way to Jupiter, we’ve looked back at home and managed to take this amazing image.”

“Earth looking much like any other planet or star from a distance is glorious as this somewhat average looking “star” is home to all of humanity. Our companion, the moon, so beautiful and important to us, stands out even less.”

“We appear almost average and inconspicuous, yet all of our history originates here. It makes one wonder just how many other planets or solar systems might contain life like ours,” Bolton told me.

Juno casts a shadow back toward Earth and Space Shuttle Launch Pad 39A and the shuttle crawler way (at left) seconds after liftoff from adjacent Launch Pad 41 at Cape Canaveral, Florida. View from the VAB Roof. Credit: Ken Kremer

The Juno team commanded the probe to take the image as part of the checkout phase of the vehicles instruments and subsystems.

“The JunoCam instrument turn on and check out were planned activities. The instrument is working great and in fact, all the instruments that we’ve turned on thus far have been working great,” Bolton added.

So far the spacecraft is in excellent health and the team has completed the checkout of the Waves instrument and its two Flux Gate Magnetometer sensors and deployment of its V-shaped electric dipole antenna.

“We have a couple more instruments still to do,” Bolton noted.

The team reports that Juno also performed its first precession, or reorientation maneuver, using its thrusters and that the first trajectory control maneuver (TCM-1) was cancelled as unnecessary because of the extremely accurate targeting provided by the Atlas V rocket.

The portrait shot is actually not Juno’s last photo of her home.

The 8000 pound (3,600 kilogram) probe will fly by Earth once more on October 9, 2013 for a gravity assisted speed boost of 16,330 MPH (7.3 km/sec) to accelerate Juno past the asteroid belt on its long journey to the Jovian system.

Juno soars skyward to Jupiter on Aug. 5 from launch pad 41 at Cape Canaveral Air Force Station at 12:25 p.m. EDT. View from the VAB roof. Credit: Ken Kremer

JunoCam will collect new photos and the other science instruments will make measurements as Juno cartwheels past Earth during the slingshot to Jupiter.

Juno is on a 5 year and 1.7 Billion mile (2.8 Billion km) trek to the largest planet in our solar system. When she arrives at Jupiter on July 4, 2016, Juno will become the first polar orbiting spacecraft at the gas giant.

During a one year science mission – entailing 33 orbits lasting 11 days each – the probe will plunge to within about 3000 miles (5000 km) of the turbulent cloud tops and collect unprecedented new data that will unveil the hidden inner secrets of Jupiter’s genesis and evolution.

The goal is to find out more about the planets origins, interior structure and atmosphere, observe the aurora, map the intense magnetic field and investigate the existence of a solid planetary core.

“This is a remarkable sight people get to see all too rarely,” said Bolton in a NASA statement about the Earth-Moon photo. “This view of our planet shows how Earth looks from the outside, illustrating a special perspective of our role and place in the universe. We see a humbling yet beautiful view of ourselves.”

NASA’s Jet Propulsion Laboratory manages the Juno mission. The spacecraft was designed and built by Lockheed Martin Space Systems, Denver.

Juno and Booster Streak Across the Stars
NASA's Juno spacecraft and its spent Centaur upper rocket stage are captured in this telescope view as they move across the field of stars. The five-minute, timed exposure was acquired on Aug. 5 11:18pm Eastern time (Aug. 6 at 3:18 UTC) when Juno was at a distance of about 195,000 miles (314,000 kilometers) from Earth. The images were taken remotely by amateur astronomer Scott Ferguson using Global Rent-a-Scope's GRAS-016 Takahashi Widefield Refractor, which is located in Nerpio, Spain. Credit: Scott Ferguson
Juno Spacecraft Cruise Trajectory to Jupiter
This graphic shows Juno's trajectory, or flight path, from Earth to Jupiter. The spacecraft travels around the Sun, to a point beyond the orbit of Mars where it fires its main engine a couple of times. These deep space maneuvers set up the Earth flyby maneuver that occurs approximately two years after launch. The Earth flyby gives Juno the boost in velocity it needs to coast all the way to Jupiter. Juno arrives at Jupiter in July 2016. Credit: NASA/JPL-Caltech
View of Juno’s position on Aug. 24, 2011 nearly 6 million miles distant from Earth visualized by NASA’s Eyes on the Solar System website.

Read my continuing features about Juno
Juno Blasts off on Science Trek to Discover Jupiter’s Genesis
Juno Jupiter Orbiter poised at Launch Pad for Aug. 5 Blastoff
JUNO Orbiter Mated to Mightiest Atlas rocket for Aug. 5 Blastoff to Jupiter
Solar Powered Jupiter bound JUNO lands at Kennedy Space Center

In Their Own Words: Experts Talk Juno

Several scientists and experts discussed the Juno mission to Jupiter with Universe Today. Photo Credit: Alan Walters/awaltersphoto.com

CAPE CANAVERAL Fla. – Many experts took time out of their hectic schedules to talk with Universe Today in the day leading up to the launch of the Juno spacecraft. Some even took the time to talk to us just minutes before the probe was scheduled to be launched on its mission. Check out what they had to say below:

Juno Project Scientist Steve Levin was at Kennedy Space Center to watch the Juno probe begin its five-year journey to Jupiter. He took a few minutes of his time to talk about what his expectations are for this mission.

Levin has been with JPL since 1990, one of the previous projects he worked on is the Planck mission which launched in 2009.

Levin believes that Juno could fundamentally change the way we view Jupiter. He was one of many VIPs that descended on Kennedy Space Center to watch as Juno thundered to orbit atop at Atlas V rocket.

Sami Asmar is part of the science team that is working on the Juno project. He was at the rollout of the Atlas rocket to the pad. Here is what he had to say about the mission (note the Atlas rocket moving out behind him).

Bill Nye the Science Guy was a very busy man while at Kennedy Space Center. He still took the time to chat with Universe Today about his views on this mission. Unfortunately, with little time to spare, we had to conduct the interview within minutes of the first launch attempt. A good chunk of Nye’s interview – was drowned out by the lead up to the countdown!

The usual launch of an Atlas consists of the launch team coming in, pushing a button and going home – the launch vehicle is that reliable. This day, things occurred quite differently. A technical issue coupled with a wayward boat that had drifted too close to the launch pad saw the launch time slip from 11:34 a.m. EDT to 12:25 p.m. When the rocket did take off however it was a spectacular sight to behold, faster than other iterations of the Atlas, it roared off the pad, sending Juno on its way to Jupiter.

Juno Blasts off on Science Trek to Discover Jupiter’s Genesis

[/caption]

NASA’s solar powered Juno spacecraft blasted off today (Aug.5)from Cape Canaveral today to begin a 2.8 billion kilometer science trek to discover the genesis of Jupiter hidden deep inside the planet’s interior.

Upon arrival at Jupiter in July 2016, JUNO will fire its braking rockets and go into polar orbit and circle the planet 33 times over about one year. The goal is to find out more about the planets origins, interior structure and atmosphere, observe the aurora, map the intense magnetic field and investigate the existence of a solid planetary core.

The spacecraft is healthy and the solar panels successfully deployed.

Check out the photo album of Juno’s launch from the Universe Today team of Alan Walters and Ken Kremer.

“Jupiter is the Rosetta Stone of our solar system,” said Scott Bolton, Juno’s principal investigator from the Southwest Research Institute in San Antonio. “It is by far the oldest planet, contains more material than all the other planets, asteroids and comets combined and carries deep inside it the story of not only the solar system but of us. Juno is going there as our emissary — to interpret what Jupiter has to say.”

Juno was launched atop a powerful Atlas V rocket augmented by 5 solid rocket boosters – built by United Launch Alliance

JUNO blasts off for Jupiter on Aug. 5. Credit: Alan Walters (awaltersphoto.com)

“Today, with the launch of the Juno spacecraft, NASA began a journey to yet another new frontier,” NASA Administrator Charles Bolden said. “The future of exploration includes cutting-edge science like this to help us better understand our solar system and an ever-increasing array of challenging destinations.”

Juno Launch - View from the VAB Roof
Atlas V liftoff with JUNO to Jupiter on Aug. 5 from Cape Canaveral Air Force Station. Credit: Ken Kremer
Juno Launch - View from the VAB Roof
Atlas V liftoff with JUNO to Jupiter on Aug. 5 from Cape Canaveral Air Force Station. Credit: Ken Kremer (kenkremer.com)
Juno Launch - View from the VAB Roof
JUNO blasts off for Jupiter on Aug. 5 atop an Atlas V rocket from Cape Canaveral Air Force Station at 12:25 p.m. EDT.

Credit: Ken Kremer (kenkremer.com)

Send Ken your Juno launch photos to post at Universe Today

Read my continuing features about Juno
Juno Jupiter Orbiter poised at Launch Pad for Aug. 5 Blastoff
JUNO Orbiter Mated to Mightiest Atlas rocket for Aug. 5 Blastoff to Jupiter
Solar Powered Jupiter bound JUNO lands at Kennedy Space Center

Juno Jupiter Orbiter poised at Launch Pad for Aug. 5 Blastoff

[/caption]

The Atlas V rocket that will power NASA’s new Juno science probe to Jupiter was rolled out to the launch pad at Space Launch Complex 41 and now sits poised for blastoff on Friday, Aug. 5 at 15:34 UT (11:34 a.m. EDT) from Cape Canaveral Air Force Station in Florida.

The Atlas V booster rocket was pushed out of its protective hanger, known as the Vertical Integration Facility, and towards Pad 41 this morning starting at 8:01 a.m. and took about 40 minutes to reach its destination.

Weather forecasters continues to call for a 70 percent chance of favorable conditions at launch time, but the approach of Tropical Storm Emily could throw a wrench in NASA’s plans depending on the track following by the storm over the remaining prelaunch period.

According to continuing weather updates, Emily is dissipating.

Juno Jupiter Orbiter encapsulated inside Payload Fairing atop Atlas V Rocket at Pad 41. NASA’s Juno science spacecraft sits inside the 5 meter diameter payload fairing which is bolted on top of an Atlas V rocket. Credit: Ken Kremer (kenkremer.com)

Managers approved Juno for flight at this morning’s Launch Readiness Review. The 4 ton Juno spacecraft will embark on a five year trek to Jupiter, our solar system’s largest planet and seek to understand the ingredients necessary for planetary formations.

Juno is perched inside a 5 meter diameter payload fairing and mated to the most powerful version of the Atlas V rocket – an Atlas 551 – with 2.4 million pounds of liftoff thrust. The 20 story tall Atlas 551 uses a standard Atlas booster with five solid rocket boosters in the first stage and a single engine Centaur in the second stage.

The launch window extends for 69 minutes.

The Atlas V is built by United Launch Alliance (ULA).

Juno will orbit Jupiter 33 times and search for the existence of a solid planetary core, map Jupiter’s intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet’s auroras. Each orbit lasts 11 days

The spacecraft will provide the first detailed glimpse of Jupiter’s poles via a specially designed camera. The elliptical orbit will allow Juno to avoid most of Jupiter’s harsh radiation regions that can severely damage the spacecraft systems.

See my photo album from the launch pad published here.

Atlas and Juno at Space Launch Complex 41 at Cape Canaveral Air Force Station, Florida. Juno is slated for an Aug. 5 blastoff to Jupiter. 465,000 gallon Liquid Oxygen tank at right. Credit: Ken Kremer
A bank of remote cameras set up to record the blastoff of Juno spacecraft. Credit: Ken Kremer
Atlas V, Juno and the Flame Trench at Space Launch Complex 41 at Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer
Atlas and Juno begin wheeling out from the Vertical Integration Facilty (VIF) to launch pad at Space Launch Complex 41 at Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer (kenkremer.com)

Read my continuing features about Juno
JUNO Orbiter Mated to Mightiest Atlas rocket for Aug. 5 Blastoff to Jupiter
Solar Powered Jupiter bound JUNO lands at Kennedy Space Center for blastoff

NASA Unveils Thrilling First Full Frame Images of Vesta from Dawn

[/caption]

NASA has just released the first full frame images of Vesta– and they are thrilling! The new images unveil Vesta as a real world with extraordinarily varied surface details and in crispy clear high resolution for the first time in human history.

Vesta appears totally alien and completely unique. “It is one of the last major uncharted worlds in our solar system,” says Dr. Marc Rayman, Dawn’s chief engineer and mission manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “Now that we are in orbit we can see that it’s a unique and fascinating place.”

“We have been calling Vesta the smallest terrestrial planet,” said Chris Russell, Dawn’s principal investigator at the UCLA. “The latest imagery provides much justification for our expectations. They show that a variety of processes were once at work on the surface of Vesta and provide extensive evidence for Vesta’s planetary aspirations.”

Dawn launch on September 27, 2007 by a Delta II Heavy rocket from Cape Canaveral Air Force Station, Florida. Credit: Ken Kremer

The newly published image (shown above) was taken at a distance of 3,200 miles (5,200 kilometers) by Dawn’s framing camera as the probe continues spiraling down to her initial science survey orbit of some 1,700 miles (2,700 km) altitude. The new images show the entire globe all the way since the giant asteroid turns on its axis once every five hours and 20 minutes.

Vesta and its new moon – Dawn – are approximately 114 million miles (184 million kilometers) distant away from Earth.

“The new observations of Vesta are an inspirational reminder of the wonders unveiled through ongoing exploration of our solar system,” said Jim Green, planetary division director at NASA Headquarters in Washington.

The Dark Side of Vesta Captured by Dawn
NASA's Dawn spacecraft obtained this image over the northern hemisphere with its framing camera on July 23, 2011. It was taken from a distance of about 3,200 miles (5,200 kilometers) away from the giant asteroid Vesta. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

Dawn was launched atop a Delta II Heavy booster rocket in September 2007, took a gravity assist as it flew past Mars and has been thrusting with exotic ion propulsion for about 70 percent of the time ever since.

Dawn will spend 1 year collecting science data in orbit around Vesta before heading off to the Dwarf Planet Ceres.

The science team has just completed their press briefing. Watch for my more detailed report upcoming soon.

And don’t forget JUNO launches on Aug 5 – It’s an exciting week for NASA Space Science and I’ll be reporting on the Jupiter orbiter’s blastoff and more – as Opportunity closes in on Spirit Point !

NASA’s groundbreaking interplanetary science is all inter connected – because Vesta and Ceres failed to form into full-fledged planets thanks to the disruptive influence of Jupiter.

Read my prior features about Dawn
Dawn Spirals Down Closer to Vesta’s South Pole Impact Basin
First Ever Vesta Vistas from Orbit – in 2D and 3D
Dawn Exceeds Wildest Expectations as First Ever Spacecraft to Orbit a Protoplanet – Vesta
Dawn Closing in on Asteroid Vesta as Views Exceed Hubble
Dawn Begins Approach to Asteroid Vesta and Snaps First Images
Revolutionary Dawn Closing in on Asteroid Vesta with Opened Eyes

JUNO Orbiter Mated to Mightiest Atlas rocket for Aug. 5 Blastoff to Jupiter

[/caption]

In less than one week’s time, NASA’s $1.1 Billion Juno probe will blast off on the most powerful Atlas V rocket ever built and embark on a five year cruise to Jupiter where it will seek to elucidate the mysteries of the birth and evolution of our solar system’s largest planet and how that knowledge applies to the remaining planets.

The stage was set for Juno’s liftoff on August 5 at 11:34 a.m. after the solar-powered spacecraft was mated atop the Atlas V rocket at Space Launch Complex 41 at Cape Canaveral and firmly bolted in place at 10:42 a.m. EDT on July 27.

“We’re about to start our journey to Jupiter to unlock the secrets of the early solar system,” said Scott Bolton, the mission’s principal investigator from the Southwest Research Institute in San Antonio. “After eight years of development, the spacecraft is ready for its important mission.”

Inside the Vertical Integration Facility at Space Launch Complex 41, the Juno spacecraft, enclosed in an Atlas payload fairing, is in position on top of its Atlas launch vehicle. The spacecraft was prepared for launch in the Astrotech Space Operations' payload processing facility in Titusville, Fla. Credit: NASA/Cory Huston

The launch window for Juno extends from Aug. 5 through Aug. 26. The launch time on Aug. 5 opens at 11:34 a.m. EDT and closes at 12:43 p.m. EDT. Juno is the second mission in NASA’s New Frontiers program.

JUNO’s three giant solar panels will unfurl about five minutes after payload separation following the launch, said Jan Chodas, Juno’s project manager at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

The probe will cartwheel through space during its five year trek to Jupiter.

Upon arrival in July 2016, JUNO will fire its braking rockets and go into polar orbit and circle Jupiter 33 times over about one year. The goal is to find out more about the planet’s origins, interior structure and atmosphere, observe the aurora, map the intense magnetic field and investigate the existence of a solid planetary core.

Hoisting Juno inside the payload fairing at Space Launch Complex 41. Credit: NASA/Cory Huston

“Juno will become the first polar orbiting spacecraft at Jupiter. Not only are we over the poles, but we’re getting closer to Jupiter in our orbit than any other spacecraft has gone,” Bolton elaborated at a briefing for reporters at the Kennedy Space Center. “We’re only 5,000 kilometers above the cloud tops and so we’re skimming right over those cloud tops and we’re actually dipping down beneath the radiation belts, which is a very important thing for us. Because those radiation belts at Jupiter are the most hazardous region in the entire solar system other than going right to the sun itself.”

“Jupiter probably formed first. It’s the largest of all the planets and in fact it’s got more material in it than all the rest of the solar system combined. If I took everything in the solar system except the sun, it could all fit inside Jupiter. So we want to know the recipe.”

Watch for my continuing updates and on-site launch coverage of Juno, only the 2nd probe from Earth to ever orbit Jupiter. Galileo was the first.

Solar Powered Jupiter bound JUNO lands at Kennedy Space Center for blastoff

[/caption]

Juno, NASA’s next big mission bound for the outer planets, has arrived at the Kennedy Space Center to kick off the final leg of launch preparations in anticipation of blastoff for Jupiter this summer.

The huge solar-powered Juno spacecraft will skim to within 4800 kilometers (3000 miles) of the cloud tops of Jupiter to study the origin and evolution of our solar system’s largest planet. Understanding the mechanism of how Jupiter formed will lead to a better understanding of the origin of planetary systems around other stars throughout our galaxy.

Juno will be spinning like a windmill as it fly’s in a highly elliptical polar orbit and investigates the gas giant’s origins, structure, atmosphere and magnetosphere with a suite of nine science instruments.

Technicians at Astrotech's payload processing facility in Titusville, Fla. secure NASA's Juno spacecraft to the rotation stand for testing. The solar-powered spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins. Credit: NASA/Jack Pfaller

During the five year cruise to Jupiter, the 3,600 kilogram probe will fly by Earth once in 2013 to pick up speed and accelerate Juno past the asteroid belt on its long journey to the Jovian system where it arrives in July 2016.

Juno will orbit Jupiter 33 times and search for the existence of a solid planetary core, map Jupiter’s intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet’s auroras.

The mission will provide the first detailed glimpse of Jupiter’s poles and is set to last approximately one year. The elliptical orbit will allow Juno to avoid most of Jupiter’s harsh radiation regions that can severely damage the spacecraft systems.

Juno was designed and built by Lockheed Martin Space Systems, Denver, and air shipped in a protective shipping container inside the belly of a U.S. Air Force C-17 Globemaster cargo jet to the Astrotech payload processing facility in Titusville, Fla.

Juno undergoes acoustics testing at Lockheed Martin in Denver where the spacecraft was built. Credit: NASA/JPL-Caltech/Lockheed Martin

This week the spacecraft begins about four months of final functional testing and integration inside the climate controlled clean room and undergoes a thorough verification that all its systems are healthy. Other processing work before launch includes attachment of the long magnetometer boom and solar arrays which arrived earlier.

Juno is the first solar powered probe to be launched to the outer planets and operate at such a great distance from the sun. Since Jupiter receives 25 times less sunlight than Earth, Juno will carry three giant solar panels, each spanning more than 20 meters (66 feet) in length. They will remain continuously in sunlight from the time they are unfurled after launch through the end of the mission.

“The Juno spacecraft and the team have come a long way since this project was first conceived in 2003,” said Scott Bolton, Juno’s principal investigator, based at Southwest Research Institute in San Antonio, in a statement. “We’re only a few months away from a mission of discovery that could very well rewrite the books on not only how Jupiter was born, but how our solar system came into being.”

Juno is slated to launch aboard the most powerful version of the Atlas V rocket – augmented by 5 solid rocket boosters – from Cape Canaveral, Fla. on August 5. The launch window extends through August 26. Juno is the second mission in NASA’s New Frontiers program.

NASA’s Mars Curiosity Rover will follow Juno to the Atlas launch pad, and is scheduled to liftoff in late November 2011. Read my stories about Curiosity here and here.

Because of cuts to NASA’s budget by politicians in Washington, the long hoped for mission to investigate the Jovian moon Europa may be axed, along with other high priority science missions. Europa may harbor subsurface oceans of liquid water and is a prime target in NASA’s search for life beyond Earth.

Technicians inside the clean room at Astrotech in Titusville, Fla. guide NASA's Juno spacecraft, as it is lowered by overhead crane, onto the rotation stand for testing. Credit: NASA/Jack Pfaller
Technicians at Astrotech unfurl solar array No. 1 with a magnetometer boom that will help power NASA's Juno spacecraft on a mission to Jupiter. Credit: NASA
Juno's interplanetary trajectory to Jupiter. Juno will launch in August 2011 and fly by Earth once in October 2013 during its 5 year cruise to Jupiter. Click to enlarge. Credit: NASA/JPL

Astronomy Without A Telescope – Solar Or RTG?

[/caption]

It used to be the case that if you wanted to send a spacecraft mission out past the asteroid belt, you’d need a chunk of plutonium-238 to generate electric power – like for Pioneers 10 and 11, Voyagers 1 and 2, Galileo, Cassini, even Ulysses which just did a big loop out and back to get a new angle on the Sun – and now New Horizons on its way to Pluto.

But in 2011, the Juno mission to Jupiter is scheduled for launch – the first outer planet exploration mission to be powered by solar panels. And also scheduled for 2011, in another break with tradition – Curiosity, the Mars Science Laboratory will be the first Mars rover to be powered by a plutonium-238 radioisotope thermoelectric generator – or RTG.

I mean OK, the Viking landers had RTGs, but they weren’t rovers. And the rovers (including Sojourner) had radioisotope heaters, but they weren’t RTGs.

So, solar or RTG – what’s best? Some commentators have suggested that NASA’s decision to power Juno with solar is a pragmatic one – seeking to conserve a dwindling supply of RTGs – which have a bit of a PR problem due to the plutonium.

However, if it works, why not push the limits of solar? Although some of our longest functioning probes (like the 33 year old Voyagers) are RTG powered, their long-term survival is largely a result of them operating far away from the harsh radiation of the inner solar system – where things are more likely to break down before they run out of power. That said, since Juno will lead a perilous life flying close to Jupiter’s own substantial radiation, longevity may not be a key feature of its mission.

Perhaps RTG power has more utility. It should enable Curiosity to go on roving throughout the Martian winter – and perhaps manage a range of analytical, processing and data transmission tasks at night, unlike the previous rovers.

With respect to power output, Juno’s solar panels would allegedly produce a whopping 18 kilowatts in Earth orbit, but will only manage 400 watts in Jupiter orbit. If correct, this is still on par with the output of a standard RTG unit – although a large spacecraft like Cassini can stack several RTG units together to generate up to 1 kilowatt.

So, some pros and cons there. Nonetheless, there is a point – which we might position beyond Jupiter’s orbit now – where solar power just isn’t going to cut it and RTGs still look like the only option.

Left image: a plutonium-238 ceramic pellet glowing red hot, like most concentrated ceramicised radioisotopes will do. Credit: Los Alamos National Laboratory. Right image: the Apollo 14 ALSEP RTG, almost identical to Apollo 13's RTG which re-entered Earth's atmosphere with the demise of the Aquarius lunar module. Credit: NASA

RTGs take advantage of the heat generated by a chunk of radioactive material (generally plutonium 238 in a ceramic form), surrounding it with thermocouples which use the thermal gradient between the heat source and the cooler outer surface of the RTG unit to generate current.

In response to any OMG it’s radioactive concerns, remember that RTGs travelled with the Apollo 12-17 crews to power their lunar surface experiment packages – including the one on Apollo 13 – which was returned unused to Earth with the lunar module Aquarius – the crew’s life boat until just before re-entry. Allegedly, NASA tested the waters where the remains of Aquarius ended up and found no trace of plutonium contamination – much as expected. It’s unlikely that its heat tested container was damaged on re-entry and its integrity was guaranteed for ten plutonium-238 half-lives, that is 900 years.

In any case, the most dangerous thing you can do with plutonium is to concentrate it. In the unlikely event that an RTG disintegrates on Earth re-entry and its plutonium is somehow dispersed across the planet – well, good. The bigger worry would be that it somehow stays together as a pellet and plonks into your beer without you noticing. Cheers.