Posted on by Jon Voisey

STEREO Looks at the Sun; Finds Planets

STEREO spacecraft. Credit: NASA

[/caption]

The primary mission of the twin STEREO probes is to explore the 3-dimensional makeup of our Sun. Each craft carries a variety of instruments. One of them, the Heliospheric Imager (HI), doesn’t look directly at the Sun, but rather, explores a wide field near the Sun in order to explore the physics of coronal mass ejections (CMEs), in particular, ones aimed at the Earth. But while not focusing on solar ejections, the HI is free to make many other observations, including its first detection of an extrasolar planet.

As the Heliospheric Imager stares at the space between the Earth and Sun, it has made many novel observations. The device first opened its shutters in 2006 the instrument has observed the interaction of CMEs with the atmosphere of Venus, the stripping of a tail of a comet by a CME, atomic iron in a comet’s tail, and “the very faint optical emission associated with so-called Corotating Interaction Regions (CIRs) in interplanetary space, where fast-flowing Solar wind catches up with slower wind regions.”

The spacecraft allows for long periods of time to stare at patches of sky as the satellites precede and follow Earth in its orbit. The spacecraft is able to take pictures roughly every 40 minutes for almost 20 days in a row giving excellent coverage. As a result, the images taken have the potential to be used for detailed survey studies. Such information is useful for conducting variable star studies and a recent summary of findings from the mission reported the detection of 263 eclipsing variable stars, 122 of which were not previously classified as such.

Another type of variable star observed by the STEREO HI, was the cataclysmic sort, in particular, V 471 Tau. This red giant/white dwarf binary in the Hyades star cluster is a strong source of interest for stellar astrophysicists because the system is suspected to be a strong candidate for a type Ia supernova as the red giant dumps mass onto its high mass, white dwarf companion. The star system is extremely erratic in its light output and observations could help astronomers understand how such systems evolve.

Although planetary hunting is at the very edge of the capabilities of the HI’s limitations, eclipses caused by planet sized objects are feasible for many of the brighter stars in the field of view as dim as approximately 8th magnitude. Around one star, HD 213597, the STEREO team reported the detection of an object that seems too small to be a star based on the light curve alone. However, follow up studies will be necessary to pin down the object’s mass more accurately.

Posted on by Nancy Atkinson

STS-133 Crew Pays Tribute to Shuttle Discovery

The STS-133 crew sent down a video from orbit today where they each paid tribute to the legacy of space shuttle Discovery. My favorite line was from Nicole Stott: “I’m looking forward to bringing her home to the people who care for her the most, to the time when we are on the runway and can look back and still see her standing on her own gear, with her own proud wings holding her up before she goes back to that hanger for the last time.”

Posted on by Nancy Atkinson

Aged Voyager 1 Does In-flight Gymnastics for Science

Voyager 1 Mission
Artist impression of Voyager 1, the first probe to traverse the heliosheath (NASA)

[/caption]

She might be old, but she’s still got it where it counts. The 33-year old Voyager 1 probe, flying out near the edge of the solar system conducted a roll program, spinning 70 degrees counterclockwise, and held the position by spinning gyroscopes for two hours, 33 minutes. Voyager performed its in-flight gymnastics on March 7, 2011 and scientists hope the maneuver will help answer the question of which direction is the sun’s stream of charged particles turns when it nears the edge of the solar system.

“Even though Voyager 1 has been traveling through the solar system for 33 years, it is still a limber enough gymnast to do acrobatics we haven’t asked it to do in 21 years,” said Suzanne Dodd, Voyager project manager, based at NASA’s Jet Propulsion Laboratory. “It executed the maneuver without a hitch, and we look forward to doing it a few more times to allow the scientists to gather the data they need.”

Voyager needed to get in the right orientation to enable its Low Energy Charged Particle instrument to gather data.

The last time either of the two Voyager spacecraft rolled and stopped in a gyro-controlled orientation was Feb. 14, 1990, when Voyager 1 snapped a family portrait of the planets. See the image here.

The two Voyager spacecraft are traveling through a turbulent area known as the heliosheath,the outer shell of a bubble around our solar system created by the solar wind. The solar wind is traveling outward from the sun at a million miles per hour. Scientists think the wind must turn as it approaches the heliosheath where it makes contact with the interstellar wind — , which originates in the region between stars.

In June 2010, when Voyager 1 was about 17 billion kilometers (about 11 billion miles) away from the sun, data from the Low Energy Charged Particle instrument began to show that the net outward flow of the solar wind was zero. That zero reading has continued since. The Voyager science team doesn’t think the wind has disappeared in that area, but perhaps has just turned a corner. But where does it go from there: up, down or to the side?

“Because the direction of the solar wind has changed and its radial speed has dropped to zero, we have to change the orientation of Voyager 1 so the Low Energy Charged Particle instrument can act like a kind of weather vane to see which way the wind is now blowing,” said Edward Stone, Voyager project manager. “Knowing the strength and direction of the wind is critical to understanding the shape of our solar bubble and estimating how much farther it is to the edge of interstellar space.”

Voyager engineers performed a test roll and hold back on Feb. 2, just to make sure the spacecraft was still capable. No problems for the old girl, and spacecraft had no problem in reorienting itself and locking back onto its guide star, Alpha Centauri.

This artist's concept shows NASA's two Voyager spacecraft exploring a turbulent region of space known as the heliosheath, the outer shell of the bubble of charged particles around our sun. Image credit: NASA/JPL-Caltech

There will be five more of these maneuvers over the next seven days, with the longest hold lasting three hours 50 minutes. The Voyager team plans to execute a series of weekly rolls for this purpose every three months.

Over the next few months, scientists will analyze the data.

“We do whatever we can to make sure the scientists get exactly the kinds of data they need, because only the Voyager spacecraft are still active in this exotic region of space,” said Jefferson Hall, Voyager mission operations manager at JPL. “We were delighted to see Voyager still has the capability to acquire unique science data in an area that won’t likely be traveled by other spacecraft for decades to come.”

Voyager 2 was launched on Aug. 20, 1977. Voyager 1 was launched on Sept. 5, 1977. On March 7, Voyager 1 was 17.4 billion kilometers (10.8 billion miles) away from the sun. Voyager 2 was 14.2 billion kilometers (8.8 billion miles) away from the sun, on a different trajectory.

The solar wind’s outward flow has not yet diminished to zero where Voyager 2 is exploring, but that may happen as the spacecraft approaches the edge of the bubble in the years ahead.

Voyager is just another good old girl.

Source: JPL

Posted on by Nancy Atkinson

Best Images from STS-133: Discovery’s Final Mission in Pictures

Discovery leaving the ISS on March 7, 2011 for the final time. Credit: NASA

[/caption]

As space shuttle Discovery prepares to return home from its final mission to space, let’s take a look back at the STS-133 mission, an historic “last” for the program’s most-traveled shuttle. “I think the legacy that this shuttle has made for herself is just nothing short than cause for celebration,” said mission specialist Michael Barratt during press conference from orbit on March 8.

“It’s going to be sad when it’s over, when we land tomorrow or the next day,” said STS-133 commander Steve Lindsey. “The hardest part of this for me is giving up the capability. It can do everything except leave low-Earth orbit…There is not a single thing wrong with her. Every single system and every piece of every system is working just like it’s brand new.”

After a successful launch, the Remote Manipulator System/Orbiter Boom Sensor System (RMS/OBSS) equipped with special cameras, begins to conduct thorough inspections of the shuttle's thermal tile system on flight day 2. Photo credit: NASA
This view of the nose, the forward underside and crew cabin of the space shuttle Discovery was provided by an Expedition 26 crew member during a survey of the approaching STS-133 vehicle prior to docking with the International Space Station. Credit: NASA
ISS tally ho! A view the space station as Discovery approaches for docking. Compare this image with one below, taken as Discovery departs to see the addition of the PMM. Credit: NASA
Backdropped by a blue and white part of Earth, space shuttle Discovery is featured in this image photographed by an Expedition 26 crew member as the shuttle approaches the International Space Station during STS-133 rendezvous and docking operations. Docking occurred at 2:14 p.m. (EST) on Feb. 26, 2011. A Russian Progress spacecraft docked to the space station is also featured in the image. Credit: NASA
A view of the docked space shuttle Discovery during the STS-133 mission, along with and the Canadian-built robot Dextre, and other parts of the ISS. Credit: NASA
European Space Agency astronaut Paolo Nespoli (left), Expedition 26 flight engineer; and NASA astronaut Steve Bowen, STS-133 mission specialist, are pictured in the Quest airlock of the International Space Station as they prepare for the start of the mission's first spacewalk. Credit: NASA
Astronauts Steve Bowen and Alvin drew work in tandem on one of the truss sections of the ISS during the first spacewalk of the STS-133 mission. Credit: NAS
Astronaut Alvin Drew during the first spacewalk of the STS-133 mission. Credit: NASA

The first spacewalk of the mission lasted six-hours and 34-minutes. Alvin Drew and Steve Bowen installed a power extension cable, move a failed ammonia pump module to the External Stowage Platform 2 on the Quest Airlock for return to Earth at a later date, installed a camera wedge on the right hand truss segment, installed extensions to the mobile transporter rail and exposed the Japanese “Message in a Bottle” experiment to space.

Cady Coleman, Expedition 26 flight engineer, is pictured near a Japanese-designed metal cylinder floating freely in the Destiny laboratory of the International Space Station while space shuttle Discovery remains docked with the station. On Feb. 28, spacewalkers Steve Bowen and Alvin Drew opened and 'filled' the cylinder, named "Message in a Bottle", with space, or rather the vacuum of outer space, and then sealed it to be brought back to Earth with the Discovery crew. Credit: NAS
The newly-attached Permanent Multipurpose Module (PMM) and a docked Russian Soyuz spacecraft. Credit: NASA
NASA astronauts Scott Kelly (foreground), Expedition 26 commander; and Steve Lindsey, STS-133 commander, are pictured in the newly-installed Permanent Multipurpose Module (PMM) of the International Space Station. Credit: NASA
Backdropped by Earth's horizon and the blackness of space, this view shows the Cupola of the International Space Station and a docked Russian Progress spacecraft, taken during the STS-133 mission. Credit: NASA
Nicole Stott, STS-133 mission specialist, is pictured in the Cupola of the International Space Station. Credit: NASA
Alvin Drew, STS-133 mission specialist, is pictured in his sleeping bag, which is attached in the Columbus laboratory of the International Space Station. Credit: NASA
The crews from STS-133 and the ISS Expedition 26 in the newly installed Permanent Multipurpose Module. Credit: NASA

Joint crew photo inside the newest module, the PMM — which is basically a big storage closet for the ISS. The STS-133 crew members, all attired in red shirts(from left)are NASA astronauts Alvin Drew, Eric Boe (below), Nicole Stott, Michael Barratt, Steve Bowen and Steve Lindsey (below). The dark blue-attired Expedition 26 crew members, from bottom left, are NASA astronaut Scott Kelly, European Space Agency astronaut Paolo Nespoli, NASA astronaut Cady Coleman along with Russian cosmonaut Oleg Skripochka. In the center of the photo are Dmitry Kondratyev and Alexander Y. Kaleri.

Russian cosmonaut Dmitry Kondratyev, Expedition 26 flight engineer, moves stowage containers in the Unity node of the International Space Station. Credit: NAS
Alvin Drew works outside during the second EVA of the STS-133 mission. Credit: NASA
Anchored to a Canadarm2 mobile foot restraint, NASA astronaut Steve Bowen works outside the ISS during the second EVA of the STS-133 mission. Credit: NASA
The space shuttle Discovery as seen from the International Space Station, flying over southwestern coast of Morocco in the northern Atlantic. During a post undocking fly-around, the crew members aboard the two spacecraft collected a series of photos of each other's vehicle. Credit: NASA
Backdropped against the blackness of spaec and clouds over Earth, the International Space Station is seen from Discovery as the shuttle departed from the station. Credit: NAS
Disovery departing the ISS for the final time. Credit: NASA

Larger versions of all these images can be found at NASA’s Human Spaceflight website, under the STS-133 gallery.

Click here to see our gallery of launch images for Discovery’s final flight.

Here’s a video recap of the STS-133 mission:

Posted on by Nancy Atkinson

Enceladus’ Internal Heat Much Higher Than Predicted

Dramatic plumes, both large and small, spray water ice out from many locations along the famed "tiger stripes" near the south pole of Saturn's moon Enceladus. Credit: NASA/JPL/Space Science Institute

[/caption]

The south polar region of Enceladus is turning out to be a veritable heat pump. The fissure- and geyser-laden region on this moon of Saturn is churning out internal heat-generated power of about 15.8 gigawatts, which is approximately 2.6 times the power output of all the hot springs in the Yellowstone region, or comparable to 20 coal-fueled power stations. This is more than an order of magnitude higher than scientists had predicted, according to Carly Howett, the lead author of a study published in the Journal of Geophysical Research on March 4. Just how that much power is being generated, however, is unknown.

“The mechanism capable of producing the much higher observed internal power remains a mystery and challenges the currently proposed models of long-term heat production,” said Howett.

2008 data from Cassini’s composite infrared spectrometer indicates a surprisingly high output of temperature from the south polar terrain on Enceladus, which makes it even more likely that liquid water exists below Enceladus’ surface, Howett said.

A 2007 study predicted the internal heat of Enceladus, if principally generated by tidal forces arising from the orbital resonance between Enceladus and another moon, Dione, could be no greater than 1.1 gigawatts averaged over the long term. Heating from natural radioactivity inside Enceladus would add another 0.3 gigawatts.

So these new readings come as a surprise.

This graphic, using data from NASA's Cassini spacecraft, shows how the south polar terrain of Saturn's moon Enceladus emits much more power than scientists had originally predicted. Images credit: NASA/JPL/SWRI/SSI

Recently, scientists studying ice particles ejected from the plumes discovered that some of the particles are salt-rich, and are probably frozen droplets from a saltwater ocean in contact with Enceladus’ mineral-rich rocky core. The presence of a subsurface ocean, or perhaps a south polar sea between the moon’s outer ice shell and its rocky interior would increase the efficiency of the tidal heating by allowing greater tidal distortions of the ice shell.

“The possibility of liquid water, a tidal energy source and the observation of organic (carbon-rich) chemicals in the plume of Enceladus make the satellite a site of strong astrobiological interest,” said Howett, who is a postdoctoral researcher at Southwest Research Institute in Boulder, Colorado.

A possible explanation of the high heat flow observed is that Enceladus’ orbital relationship to Saturn and Dione changes with time, allowing periods of more intensive tidal heating, separated by more quiescent periods. This means Cassini might be “lucky” enough to be seeing Enceladus when it’s unusually active.

The activity is centered on four roughly parallel linear trenches, 130 kilometers (80 miles) long and about 2 kilometers (1 mile) wide, informally known as the “tiger stripes.” These fissures eject great plumes of ice particles and water vapor continually into space, and have elevated temperatures due to heat leaking out of Enceladus’ interior.

Along one fissure, called Baghdad Sulcus, temperatures exceed 180 Kelvin ( – 92 C, -135 F), and may be higher than 200 Kelvin (- 73 C, -100 F). While chilly by Earth standards, peak temperatures, the temperatures are a cozy oasis compared to the numbing 50 Kelvin (-223 C, -370 F) of their surroundings.

Source: JPL

Posted on by Nancy Atkinson

Awe-Inspiring Flythrough of the Saturn System

Ever imagine creating your own IMAX movie? Cinematographer Stephen Van Vuuren is working to do just that, and has created flythough sequences from thousands of images from the Cassini spacecraft’s tour of the Saturn system. The video above is just a sampling of this non-profit, giant-screen art film effort “that takes audiences on a journey of the mind, heart and spirit from the big bang to the near future via the Cassini-Huygens Mission at Saturn,” according to the “Outside In” website.

Continue reading “Awe-Inspiring Flythrough of the Saturn System”

Posted on by Nancy Atkinson

Vast Areas of Low Latitude Subsurface Ice Found on Mars

Color image of a region in Holden Crater. Credit: NASA/JPL/University of Arizona

[/caption]

There could be more subsurface ice on Mars than previously thought, and vast stretches of it may lie just south of the equator. Indeed, one of the proposed landing sites for the Mars Science Laboratory could hold the mother lode of enticing scientific prospects. Observations from two spacecraft, the Mars Reconnaissance Orbiter and Mars Express, have revealed potential subsurface ice deposits in areas just south of the equator, including one near Holden Crater, with an estimated reservoir of perennial subsurface water ice of about 50 – 500 kg m -2 just two or three meters beneath the surface. This is the first evidence of ice at “tropical” latitudes on Mars as low as 25 degrees.


In 2009, MRO observations revealed water ice as low as 45 degrees North in a recent small impact crater, and permanent water ice at Mars’ poles is known to exist. But most robotic missions – and hopefully one day human missions – need to land closer to the equator to meet safety criteria and engineering constraints. As evidence, the four proposed landing sites for the MSL hover within 25 degrees of the equator.*

Of course, subsurface ice can’t be seen directly on Mars, but certain surface characteristics and thermal properties belie potential underground ice. The OMEGA (Observatoire pour la Minéralogie, l’Eau, les Glaces et l’Activité ) onboard Mars Express and CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) onboard the Mars Reconnaissance Orbiter use near-infrared imaging spectrometers to measure solar radiation scattered by the surface, providing spectral images that have been used to assess the composition of both minerals and condensates on the surface of Mars.

What drew scientists to this region, were observed surface distributions of seasonal CO2 frost on pole facing slopes. Carbon dioxide ice usually only forms on the surface if there is a cold layer beneath, which can come from water ice or bedrock.

But in this case, Mathieu Vincendon and his team at Brown University concluded that bedrock couldn’t be responsible for creating the observed thermal properties that stores and releases heat two or three meters beneath the surface. Evidence of a uniform layer of bedrock stretching across the equatorial region has never been seen in orbital images, which would have been revealed by erosion or impact processes.

“Using different modeling hypotheses within the range of uncertainties leads to the result that water ice is present within one meter of the surface on all 20-30° pole facing slopes down to about 25°S,” the team writes in their paper. “ The relevant thermal depths probed are 2 or 3 meters. Hence, an ice rich layer that thick is implied, which leads to an estimated reservoir of perennial subsurface water ice of about 50 – 500 kg m -2 on steep slopes.”

The team believes that the subsurface ice could be possible remnants of the last ice age on Mars, and could provide water that will be needed for the future exploration of Mars. More thermal measurements of seasonal temperature variations could help to derive more precise permafrost depths.

Holden crater is located at the edge of the subsurface water ice area at 26°S.

*Eberswalde Crater is -23.90 degrees S, Mawrth Vallis is 23.99 degrees N, Gale crater is -4.49 degrees S, and Holden is -26.4 degrees S.

Sources: arxiv, Technology Review Blog

Posted on by Jason Rhian

As Shuttle Era Ends, What Will be its Legacy?

The shuttle era is set to end this summer when Atlantis completes STS-135. What will be the program's legacy? Photo Credit: Jason Rhian

[/caption]
When it comes to space flight, the media, politicians and the public tend to focus on who was “first.” Many point to the fact that the Soviet Union was first to send both a satellite and man into orbit as the impetus behind the U.S. into the new frontier. However, the “lasts” are often lost to history, forgotten in the dusty pages of some biographer’s notes. As the shuttle era closes, there are several lasts that, so far, have gone unmentioned. More importantly, the program, as a whole, has been an incredibly powerful engine for change – both within the U.S. and abroad.

Alvin Drew is the last African-American currently scheduled to fly in the shuttle program. Additionally, there is one other last that may or may not be highlighted (if NASA gets the necessary funding for the mission) – the last woman to fly in the shuttle program – Sandra “Sandy” Magnus on STS-135. Although NASA has declared STS-135 an official mission, the funding needed to fly it, has yet to be approved.

Currently, Alvin Drew will be the last African-American to fly in the shuttle program. Photo Credit: Jason Rhian

These two “lasts” may or may not be noted by the media, many of whom give the appearance of looking down on the program. The shuttle, as Bob Crippen once said is often “bad-mouthed” for not living up the expectations laid out at the beginning of the program. Perhaps, in time, the shuttle program will be remembered as what it was – an engine that worked to remove many social barriers. The shuttle era could, one day, be regarded as the program that opened space flight to people of all races and nations.

The number of nations that have flown astronauts onboard NASA’s fleet of shuttles is far more expansive than most think. Canada, Belgium, France, Germany, Italy, the Netherlands, Spain, Switzerland, Israel, Japan, Mexico, Russia, Saudi Arabia and the Ukraine have all flown astronauts aboard the space shuttle.

During the Mercury, Gemini and Apollo Programs the crews were universally white and male. With the shuttle’s capacity for larger crews – that dynamic changed. The U.S. flew its first woman, Sally Ride, in 1984 (the Soviet Union flew its first woman, Valentina Tereshkova in 1963) the first African-American, Guy Bluford also flew that year. After that the backgrounds of the astronauts who flew on the shuttle continued to diversify.

Sandra Magnus is set to fly onboard shuttle Atlantis' STS-135 mission, she will be the last woman to fly in the shuttle program. Photo Credit: NASA

The first female pilot, Eileen Collins, flew on board STS-63 – she would go on to become the first female commander – and to return NASA to flight after the Columbia disaster on STS-114 in 2005. Charles Bolden, an African-American, commanded the first joint Russian/American shuttle mission (mission STS-61 on Discovery) and would go on to become the first African-American NASA administrator when he was selected in 2009. These are just two of numerous examples of how the shuttle has empowered different genders and races.

So while Drew’s and Magnus’ place in history may not be well remembered, those that paved the way for them as well as the shuttle’s capabilities made it all possible. Time will tell if the shuttle will be remembered for its shortcomings or if it will be remembered for allowing astronauts of all stripes to fly, for the Hubble Space Telescope to be deployed and serviced, for the International Space Station to be built and for all the other positive things that the shuttle made possible since it first flew in April of 1981.

“The shuttle has flown on such a routine basis for the past 30 years that many Americans may not realize the contributions it has made for all humankind,” said Candrea Thomas a NASA public affairs officer. “When the shuttles stop flying, I believe Americans will remember all the wonderful technologies and advancements that these amazing spacecraft, and the diverse group of people who worked on them, made possible.”

Posted on by Nancy Atkinson

Where to Next? Decadal Survey Prioritizes Future Planetary Missions

Concept for the MAX-C-Rover to Mars, a priority mission recommended for NASA

[/caption]

The planetary science community has released their “Decadal Survey” a set of recommendations and a wish list of future missions to explore the solar system. But, as panel chair Steve Squyres said in his presentation of the survey at the Lunar and Planetary Science Conference on late Monday afternoon, NASA’s current budget projections could mean the end of large, flagship missions.

“The budget we had to work with is a projection by OMB (Office of Management and Budget) of what the future of planetary exploration might look like,” Squyres said. “If implemented, it would mean the end of flagships programs in planetary science. But this is not set in stone by any means. This budget is the first step in the process from the executive branch of the government. There are many more steps involving the other branches, and Congress is answerable to its constituents, and that includes us. So those of us who care have an obligation to speak to our representatives and let them know what missions we would like to see.”

The Decadal Survey, a lengthy 400-page document supported by NASA, the National Research Council and the National Science Foundation, “transcends Congress and changes in administration and is our guiding light that moves us forward year after year, said Jim Green, NASA’s Planetary Science Chief.

Squyres said the Decadal Survey is “an extraordinary event where a governmental entity looks toward its constituency for input and actually listens to them.”

In total, the committee – made up of planetary scientists — identified 25 mission candidates for detailed studies.

Flagship missions were recommended in the report, but with the caveat that if they can’t stay under a certain budget, those missions will either be delayed or canceled. And if NASA doesn’t have enough money or cannot stay within budget, the space agency should focus on smaller, cheaper missions first. These recommendations appear to be a direct result of the money issues of the James Webb Space Telescope and the Mars Science Laboratory Rover.

Among the highest recommendations for the big flagship missions are a double rover mission to Mars working in cooperation with the European Space Agency, sending NASA’s Mars Astrobiology Explorer Cacher (MAX-C) rover, (which could be a sample return mission) and ESA’s ExoMars Rover to the Red Planet which could both help determine whether the planet ever supported life and could also help answer questions about its geologic and climatic history. NASA’s part of that joint mission should not exceed $2.5 billion, which is actually $1 billion less than the independent estimates provided to the committee. However, the panel suggested that both space agencies work to make the missions cheaper by reducing the scope of the mission (and they provided a checklist of how to do that).

The second highest recommendation for the flagship missions is to study Jupiter’s icy moon Europa and its subsurface ocean — one of the most promising environments in the solar system for supporting life. But again, NASA should fly the Jupiter Europa Orbiter (JEO) only if NASA’s budget for planetary science is increased, or if the JEO’s mission scope is made more affordable. The independent estimate put the price tag at $4.7 billion. The committee concluded that unless costs could be brought down, conducting JEO would preclude too many other important missions.

“De-scoping is a difficult thing,” Squyres said at the conclusion of his presentation. “It requires discipline, it requires leaving behind some of our most cherished hopes for what a mission might be.”

But Squyres reminded those in attendance of two famous de-scoped missions. One mission, originally called the Grand Tour ended up being cut because it was alltogether too large in scope and budget. It later became Voyager, and scientists later worked out a way to make the Grand Tour happen. The other mission was the VIRM mission to Venus, which was a radar and mapping mission to Venus, which was too expensive, and it was massively de-scoped to became the Magellan mission.

“Voyager and Magellan both revolutionized our understanding of five planets, so de-scoping — when done right — can lead to revolutionary missions,” Squyres said.

Other missions would be the first in-depth exploration of an ice giant plant – an orbiter to Uranus — and another to Saturn’s geyser-filled moon, Enceladus.

The Decadal Survey takes input from planetary scientists, and Squyres said the science community stressed the importance of smaller missions – known as New Frontier class missions — which would provide science quicker, cheaper and more frequently than the big flagship missions. Also, they said NASA should place high priority on research and development and technology funding.

Recommendations for New Frontiers missions for 2013-2022 include a Comet Surface Sample Return mission, and Io orbiter, a probe to deploy into Saturn’s atmosphere, a network of lunar landers and orbiters, and a Lunar South Pole-Aitken Basin Sample Return.

Squyres said the panel proceeded knowing their recommendations should be science-driven and but also that the missions would have to be maintainable within the projected budgetary resources. So, not just the science but the costs of the science.

“Science return per dollar — I understand science return is not highly definable in terms of cost,” Squyres said, which sometimes makes the projections difficult.

Other missions were recommend based on balance across the solar system and balance on mission size between the smaller and larger missions. Other criteria were the missions’ readiness of appropriate technologies, and availabilities of trajectories in the next 10 years — “You have to be able to get from here to there,” Squyres said.

They also recommended funding for current missions to continue or be extended including, MESSENGER, Dawn, Kepler, GRAIL, New Horizons, Juneo, Cassini, the current Mars missions, including the Mars Science Laboratory and MAVEN, and the LADEE lunar mission.

Posted on by Nancy Atkinson

Double Spaceship Sighting Alert – and last chance to see Discovery in orbit

Discovery and ISS pass over the UK on March 7, 2011, captured by Will Gater.

[/caption]

UPDATE: We’ve already got a sighting! The image above was taken this evening in the UK by science writer Will Gater.

Space shuttle Discovery undocked from the ISS on early Monday, March 7, and depending where you live, you might have an opportunity to see the two spaceships flying in tandem. This is an incredible sight, and will be the last opportunity to see Discovery in orbit, as she will be retired after she lands and completes the STS-133 mission. Spaceweather.com reports that the station and shuttle will be flying over parts of the United States and Europe Monday and Tuesday, appearing in the night sky as a closely-spaced pair of bright lights. The ISS is bigger, so will appear as the brighter object trailing the smaller Discovery as they move across the sky.

To find out if you’ll be able to see the two spaceships in your area, there are a few different sites to check out:

NASA has a Skywatch page where you can find your specific city to look for satellite sighting info.

Spaceweather.com, has a Satellite Tracker Tool. Just put in your zip code (good for the US and Canada) to find out what satellites will be flying over your house.

Heaven’s Above also has a city search, but also you can input your exact latitude and longitude for exact sighting information, helpful if you live out in the country.

Seeing the two spacecraft flying closely in tandem is a very unique and thrilling sight. Good luck!

Below, watch some of the incredible views as Discovery performed the fly-around maneuver of the ISS early Monday.