Posted on by Nancy Atkinson

13 Things That Saved Apollo 13, Part 1: Timing

Damage to the Apollo 13 spacecraft from the oxygen tank explosion. Credit: NASA

Note: To celebrate the 40th anniversary of the Apollo 13 mission, for the next 13 days, Universe Today will feature “13 Things That Saved Apollo 13,” discussing different turning points of the mission with NASA engineer Jerry Woodfill. Click here for our preview article.

Oxygen Tank two in the Apollo 13 Service Module exploded at Mission Elapsed Time (MET) 55 hours and 55 minutes, 321,860 kilometers (199,990 miles) away from Earth. If the tank was going to rupture and the crew was going to survive the ordeal, the explosion couldn’t have happened at a better time. “Not everyone agrees with all the things I’ve come up with in my research,” said NASA engineer Jerry Woodfill who has studied the Apollo 13 mission in intricate detail, “but pretty much everyone agrees on this, including Jim Lovell. The timing of when the explosion happened was key. Much earlier or later in the mission would have prevented a successful rescue.”

If the explosion happened earlier (and assuming it would have occurred after Apollo 13 left Earth orbit), the distance and time to get back to Earth would have been so great that there wouldn’t have been sufficient power, water and oxygen for the crew to survive. Had it happened much later, perhaps after astronauts Jim Lovell and Fred Haise had already descended to the lunar surface, there would not have been the opportunity to use the lunar lander as a lifeboat.

But looking at why the explosion happened when it did shows how fortuitous the timing ended up to be.

The control panel of the Apollo 13 capsule. The module is on display at the Kansas Cosmosphere and Space Center in Hutchinson, KS. Photo courtesy Kansas Cosmosphere and Space Center.

The explosion occurred when Jack Swigert flipped a switch to conduct a “stir” of the O2 tank. The Teflon insulation on the wires to the stirrer motor in O2 tank 2 had unknowingly been damaged because the manufacturer failed to update the heater design for 65 volt operation, and the tank overheated during a pre-flight test, melting the insulation. The damaged wires shorted out and the insulation ignited. The resulting fire rapidly increased pressure beyond its nominal 1,000 psi (7 MPa) limit and either the tank or the tank dome failed.

The O2 tanks were stirred in order to get an accurate reading on the gauging systems, as the cryogenic oxygen tends to solidify in the tanks, and stirring allows for a more accurate reading on the quantity of O2 remaining in the tank.

But this was not the first time the crew had been ordered to stir the tank. It was the fifth time during the mission. And most interestingly, the tanks normally were stirred approximately once every 24 hours. So, why was it stirred that often?

In what Woodfill said was a problem unrelated to what caused the explosion, the quantity sensor or gauge was not working correctly on O2 tank 2. The EECOM (Electrical Environmental and Consumables) flight controller in Houston discovered that the quantity sensor was not reading accurately, and because of that Mission Control asked the astronauts to perform additional actuations of the stirrer to try and troubleshoot why the sensor wasn’t working correctly.

So, it took five actuations until the short circuit and the resulting fire and explosion occurred. If the gauge had been working correctly and the normal stirring of the tank had been done, that would have put the time of the fifth stirring after Lovell and Haise had departed for the lunar surface, and the rescue scenario that ultimately was carried out couldn’t have happened.

“Check the arithmetic,” said Woodfill. “Five actuations at 24 hour periods amounts to a MET of 120 hours. The lunar lander would have departed for the Moon at 103.5 hours into the mission. At 120 hours into the mission, the crew of Lovell and Haise would have been awakened from their sleep period, having completed their first moon walk eight hours before. They would receive an urgent call from Jack Swigert and/or Mission Control that something was amiss with the mother ship orbiting the Moon.”

Apollo 13 crew: Jim Lovell, Jack Swigert and Fred Haise. Credit: NASA

Who knows what would have happened to the crew? The fuel cells required the liquid oxygen tanks. This meant no production of electrical power, water and oxygen. The attached lunar lander had to be available. Likely, the two ships couldn’t even have docked back together. And what if the accident had happened behind the Moon without mission control’s help? Alone in the Command module, Swigert would have had difficulty analyzing the problem. Without a fueled lunar lander descent stage attached, lacking its consumables and engines as well as the needed battery power, water and oxygen, the crippled Command Module could not have returned to Earth with live astronaut(s). Not only would Lovell and Haise have perished but Swigert’s fate would have been the same. Even if the damaged Service Module’s engine had worked, no fuel cells meant the ship would die. The situation that the Apollo 13 crew actually faced was dire, but the alternative scenario would certainly have been fatal.

Woodfill contends that the quantity sensor malfunction assured the lunar lander would be present and fully fueled at the time of the disaster. It was an extremely fortuitous event. Had it not occurred, the timing of the explosion would have been far different and the crew would have perished.

Additional Articles from the “13 Things That Saved Apollo 13” series that have now been posted:

Introduction

Part 2: The Hatch That Wouldn’t Close

Part 3: Charlie Duke’s Measles

Part 4: Using the LM for Propulsion

Part 5: Unexplained Shutdown of the Saturn V Center Engine

Part 6: Navigating by Earth’s Terminator

Part 7: The Apollo 1 Fire

Part 8: The Command Module Wasn’t Severed

Part 9: Position of the Tanks

Part 10: Duct Tape

Part 11: A Hollywood Movie

Part 12: Lunar Orbit Rendezvous

Part 13: The Mission Operations Team

Also:

Your Questions about Apollo 13 Answered by Jerry Woodfill (Part 1)

More Reader Questions about Apollo 13 Answered by Jerry Woodfill (part 2)

Final Round of Apollo 13 Questions Answered by Jerry Woodfill (part 3)

Never Before Published Images of Apollo 13’s Recovery

Listen to an interview of Jerry Woodfill on the 365 Days of Astronomy podcast.

Posted on by Nancy Atkinson

Where Is NASA Going and How Are We Going to Get There?

Constellation Program. Image Credit: NASA

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Everyone seems to be a little confused and in the dark about the direction NASA will be headed if Obama’s proposed FY2011 budget passes. Yesterday’s hastily called press briefing answered a few question, but not the big issues of where we’ll be going and how we’re going to get beyond low Earth orbit. Yes, Bolden did say that Mars is the ultimate destination but everyone knows we can’t just pick and go to Mars. NASA needs a vehicle to get there, and getting there will require doing it in incremental steps, such as going to the Moon or asteroids first. There’s no plan (yet) for a vehicle and no plans for those incremental steps. Hopefully Obama’s “Space Summit” on April 15 will provide some answers.

I’m of two minds about this whole deal.

First, I love the space shuttle. I’ve just spent two months at Kennedy Space Center. I experienced the launch of Endeavour, got to see Endeavour and Discovery up closer than I ever imagined, saw behind the scenes processing, met people who work with the shuttles every day, and talked with people whose livelihood depends on NASA sending people to space.

And admittedly, any talk of extending the shuttle program makes my heart leap just a little. It’s a beautiful, marvelous, incredible machine – many say the most complex device ever invented by humans. And why shouldn’t we keep flying it? NASA managers like Mike Moses, Mike Leinbach and John Shannon say that since the Columbia accident we now know the shuttle and understand the risks better than ever. Right now, it definitely would be safer to fly on a shuttle than to fly on a new, untested commercial rocket.

And the jobs lost – not only at KSC but at Johnson Space Center, other NASA centers and contractors — by ending the shuttle and canceling Constellation means individuals who have these incredible skill sets for getting people to space may not be needed anymore. There are things they know that just can’t be replaced, replicated or restarted five or ten years down the road.

Bolden said yesterday that there should be new jobs under the new budget which provides more money for NASA, but nobody really knows yet how many and where.

One of the most poignant questions asked by a reporter at yesterday’s press briefing came at the very end: What’s to say that when a new administration enters the White House that we won’t come back to starting over again with a whole new program?

“If we execute the budget as proposed and prove that we are on a sustainable path, that is the best protection for a subsequent administration not having to change course,” said Lori Garver, Deputy NASA Administrator. “That’s the goal, to not be in this position every four years. These technologies we will be developing will allow us to leave low Earth orbit and go to interesting places. We’ll be able to determine the best places to go, and we should have the data to do it and the capabilities to do it that are more affordable, which has been the goal since the beginning to the space program.”

So this is where my other mind kicks in.

Change is hard. It’s really hard when people’s lives and livelihood are affected. But without change, we get comfortable and getting comfortable means we do the same things over and over.

Running NASA the same way ever since the end of Apollo, while giving us the amazing vehicle that is the space shuttle, has not gotten humans beyond low Earth Orbit, and I think everyone agrees we want to be able to go other places.

Last year NASA turned 50 and there were some comments about NASA reaching middle age and acting like it, too. Change is what keeps us young, and change keeps us on our toes. When you’re willing to change and get out of your comfort zone, you make a commitment to the unknown. And that’s what NASA should be all about. Our memories can’t be bigger than our dreams.

Perhaps the hardest thing about these proposed changes to NASA is that Obama and Bolden are asking for change without telling us exactly what the change is. Maybe they don’t know yet, but this is something we can’t just figure out along the way.

There’s the famous saying that life is not about the destination but the journey, or the other saying that the best thing about being in a race is competing in it. But most journeys have a map and most races have a finish line.

If the proposed budget and plan goes through, this will give us a shot at journeying beyond. Now we just need to know where we’re going and how we’re going to get there.

I started writing this to report on yesterday’s briefing by Charlie Bolden, Lori Garver and other NASA officials, but clearly it turned into something different. Here are a few links to articles by other journalists who wrote about the briefing and what might be coming next:

Reuters: NASA Maps Plan for Revamped Space Program

NASA Chief Maps Out Space Agency’s Future Beyond Shuttle by Tariq Malik at Space.com

NASA Chief Charts Agency’s Shuttle-Less Future by Seth Borenstein, AP

The Write Stuff Blog at the Orlando Sentinel quickly distills what the changes will mean for the different NASA Centers:

Plans for Kennedy Space Center under Obama 2011 budget

What JSC can Expect from the NASA Reshuffle

What Marshall Can Expect from the NASA Reshuffle

Houston Chronicle’s Eric Berger, The SciGuy: Job Cuts Worry Space Center Boss and Answers Coming Today on NASA’s Future

Congressional Reactions to NASA’s Work Assignments by Jeff Foust at Space Politics

NASA Announces Programs and Costs for the Next Five Years by Dennis Overbye, New York Times

And finally, this NASA budget page provides links to all the NASA documents published about the new budget

Posted on by Nancy Atkinson

13 Things that Saved Apollo 13

The crew of Apollo 13 after landing safely. Credit: NASA.

On the night of April 13th, 1970, when the oxygen tank in Apollo 13’s Command and Service Module exploded, a 27-year-old engineer named Jerry Woodfill sat at his console in the Mission Evaluation Room at Johnson Space Center, monitoring the caution and warning system he helped create for the Apollo spacecraft.

“It was 9:08 pm, and I looked at the console because it flickered a few times and then I saw a master alarm come on,” Woodfill said, talking from his office at JSC where he has worked for almost 45 years. “Initially I thought something was wrong with the alarm system or the instrumentation, but then I heard Jack Swigert in my headset: “Houston, we’ve had a problem,” and then a few moments later, Jim Lovell said the same thing.”

And so began the most perilous but eventually triumphant situation ever encountered in human spaceflight.

2010 is the 40th anniversary of Apollo 13, and Universe Today had the chance to talk with Woodfill about his role in Apollo 13, a mission which many believe should have ended fatally for astronauts Jim Lovell, Fred Haise, and Jack Swigert. But it didn’t, and the mission has come to be called a “successful failure.”

What things were responsible for that success – the overcoming of odds – to rescue of the crew?

Since Woodfill was there in the thick of the action, he has some ideas on how to answer that question. But also, for the past 40 years he has studied the Apollo13 mission in intricate detail, examining all the various facets of the rescue by going through flight transcripts, debriefs, and other documents, plus he’s talked to many other people who worked during the mission. Fascinated by the turn of events and individuals involved who turned failure into success, Woodfill has come up with what he calls “13 Things That Saved Apollo 13.”

Over the next few weeks, we’ll share Woodfill’s insights and discuss each of those 13 turning points. What better way to celebrate the 40th anniversary of Apollo 13!

But for today, besides giving our readers a preview of what is to come the next 13 days, we’ll take this opportunity introduce you to Jerry Woodfill.

Jerry Woodfill working in the Apollo Mission Evaluation Room. Credit: Jerry Woodfill.

While attending Rice University on a basketball scholarship, Woodfill was inspired by President John F. Kennedy’s famous “We Choose to go to the Moon” speech delivered at Rice. Woodfill turned in his basketball shoes and focused on his studies of electrical engineering, hoping to become part of the space program.

He came on board at NASA just in time to work on helping to build the Apollo spacecraft.

“I spent years working with contractors, engineers, flight controllers and astronauts on the caution and warning system, or the alarm systems for both the lunar lander as well as the command ship,” Woodfill said.

He compared the alarm system to the lights that come on in an automobile when the battery is low or the generator isn’t working. “We had to come up with the best means of telling the astronauts they had a problem. We had to make sure the alarm system worked right. ”

Woodfill said that like most of the NASA team, he knew the workings of the command ship and lander more intimately than any of his college courses would have required, but that prepared him for any problems that might arise.

The Mission Evaluation Room. Credit: Jerry Woodfill.

During the Apollo missions Woodfill worked in the Mission Evaluation Room, which is NOT the Mission Operations Control Room (MOCR) or “Mission Control” as it is known. MER was in a building adjacent to the Mission Control building. Woodfill has written a webpage detailing the difference between the MER and MOCR.

“We were an unsung group,” Woodfill said. “We were there for mission support. We weren’t flight controllers, but we were experts. For other missions that were routine we didn’t play that big of a role, but for the Apollo 13 mission, we did play a role.”

Woodfill tends to downplay both his role and the importance of the MER. “Comparing the 1970s era MER to the Mission Operations Control Room would be akin to comparing the Queen Mary to a weekend boater’s cabin cruiser,” he said. “Likewise, comparing my role in the rescue to Gene Kranz and Glen Lunney’s would be more incomparable.”

For a truly unbiased opinion, however, Chapter 11 of Jim Lovell’s book “Lost Moon” (renamed Apollo 13 after the movie of the same name came out in 1995) details how important the people in the Mission Evaluation Room were. Yes, the “MER-men” were important!

While many may say the way Apollo 13 turned out was luck or a fortuitous turn of events, Woodfill said he tends to lean towards providence.

Over the next 13 days, perhaps we’ll find out!

And if Woodfill’s name is familiar to Universe Today readers, you may recall how he found the “lost” lesson plans of the teacher in space, Christa McAuliffe, and brought them “back to life” so to speak, as they are now being used by many teachers and Challenger Learning Centers.

Listen to an interview of Jerry Woodfill that I did for the 365 Days of Astronomy podcast.

Additional Articles in the “13 Things That Saved Apollo 13” that have now been posted:

Part 1: Timing

Part 2: The Hatch That Wouldn’t Close

Part 3: Charlie Duke’s Measles

Part 4: Using the LM for Propulsion

Part 5: Unexplained Shutdown of the Saturn V Center Engine

Part 6: Navigating by Earth’s Terminator

Part 7: The Apollo 1 Fire

Part 8: The Command Module Wasn’t Severed

Part 9: Position of the Tanks

Part 10: Duct Tape

Part 11: A Hollywood Movie

Part 12: Lunar Orbit Rendezvous

Part 13: The Mission Operations Team

Also:

Your Questions about Apollo 13 Answered by Jerry Woodfill (Part 1)

More Reader Questions about Apollo 13 Answered by Jerry Woodfill (part 2)

Final Round of Apollo 13 Questions Answered by Jerry Woodfill (part 3)

Never Before Published Images of Apollo 13’s Recovery

Posted on by Nancy Atkinson

Volcanoes on Venus May Still Be Active

The colored overlay shows the emissivity derived from VIRTIS surface brightness data, acquired by ESA¹s Venus Express mission. The high emissivity area (shown in red and yellow) is centered on the summit and the bright flows that originate there. Image courtesy NASA/JPL-Caltech/ESA; image created by Ryan Ollerenshaw and Eric DeJong of the Solar System Visualization Group, JPL.

Recent infrared data from an instrument on the Venus Express spacecraft indicate there could be active volcanism on Venus. “We are pretty sure that Venus still has volcanic activity,” said Joern Helbert and Nils Mueller from the DLR Institute of Planetary Research, members of the Visible and Infrared Thermal Imaging Spectrometer(VIRTIS) team. Nine ‘hotspots’ on Venus’ southern hemisphere have been identified as possibly active, according to a paper published in Science by an international team.

Focusing on areas that showed a lack of surface weathering – which indicates a young surface — the scientists looked at variations in surface thermal emissions to identify compositional differences in lava flows at three specific hotspots. They found that lava flows at the those areas emit abnormally high amounts of heat when compared with their surroundings. That the temperatures are higher does not indicate “heat” as such from volcanism, but means that not much rock degradation by exposure to the harsh Venusian weather took place.

For planetary scientists, that indicates recent active volcanos. How recent?

“Based on a wide range of estimates for rates of volcanism on the surface, we find an upper bound of 250 years to 2.5 million years,” lead author Suzanne Smrekar from JPL told Universe Today in an email. “From predictions about how fast rocks weather on the surface of Venus, we think they are likely on the young side of these estimates. However, there is nothing to preclude them from happening today – but we don’t have any data that demonstrates that.”
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The areas are analogous to Hawaii with volcanism, broad topographic rises, and large positive gravity anomalies suggesting mantle plumes – which are rising masses of hot molten rock.

Smrekar said the temperature variations aren’t huge. “Only a degree or two above the background temperature,” she said. “‘Hot spot’ refers to the geologic environment. On Earth, places like Hawaii where there is hot material coming up from deep inside the Earth to produce volcanism, are referred to as ‘hot spots’.”

Like on Earth, Venus’s valleys are warmer than its mountains. But the venusian atmosphere is so dense that it completely determines the temperature of the planet’s surface. This enabled the scientists to predict surface temperatures with computer models. Data obtained from VIRTIS last year shows that certain areas deviate from the predictions by as much as two or three degrees, and that was the focus of the team’s study.

Smrekar said the team was surprised at the findings. “Although we suspected that these areas could be volcanically active on geologic time scales from past data sets, this is the first data to confirm very recent volcanism, geologically speaking.”

Sources: Science, email exchange with Suzanne Smrekar, DLR

Posted on by John Carl Villanueva

Surface of the Moon

Earth's Moon
Earth's Moon

[/caption]Despite the close proximity between the Earth and the Moon, there’s a big difference between the surface of the Moon and of Earth’s. Much of the difference between the two celestial bodies is caused by the absence of the following attributes on the Moon: an atmosphere, bodies of water, and plate tectonics.

Since the Earth’s Moon doesn’t have a significant atmosphere, nothing can stop even the smallest meteoroids from striking its surface. As a result, the lunar surface is heavily cratered. As a matter of fact, tiny craters are quite common even on lunar rocks. This was observed on the Moon rocks brought home by the Apollo missions.

By contrast, small meteoroids that pass through the Earth’s atmosphere are easily vaporized and hence are not able to form craters on the land below.

The absence of liquid water on its surface has allowed the Moon to preserve much of its ancient geological features. Here on Earth, erosion can alter and cover formations over time. Plate tectonics, which is also absent on the Moon, is another big factor that makes the terrain of the two celestial bodies different.

Here on Earth, plate tectonics cause volcanic activities, earthquakes, and sea floor spreading.

Due to the lack of water and atmosphere, the lunar regolith (also called “lunar soil”) is noticeably dry and devoid of air. It also does not contain anything organic. The regolith comes from meteor impacts that has plagued the Moon since its inception.

Impact crater sizes on the lunar surface range from the tiny holes that mark lunar rocks to the really big ones like the South Pole Aitken Basin that has a diameter of approximately 2,500 km. Younger craters are superimposed over older ones. This characteristic is used by scientists to determine the relative ages of impact craters.

Basically, it has been observed that the size of impact craters on the surface of the Moon have decreased over time.

Other prominent geological features found on the surface of the Moon include maria, rilles, domes, wrinkle ridges, and grabens.

The maria, which comprise about one-third of the Moon’s near side, are made up of flows of basaltic lava formed from volcanic activities that occurred in the younger years of the Moon. They were once mistaken for seas on the surface of the Moon, hence the name. Maria is the Latin word for seas. The near side refers to the side of the Moon that is constantly facing Earth.

Here’s a list of popular craters on Earth from Universe Today.

Come October 9, 2009, LCROSS will perform a lunar impact. Find out which crater NASA has chosen for the impact. If you want to know more about the largest crater on the Moon, NASA’s got the right stuff.
There are some interesting episodes from Astronomy Cast that we’d like to recommend:
The Source of Atmospheres, the Vanishing Moon, and a Glow After Sunset
The Moon, Part 1

References:
http://www.nasa.gov/mission_pages/LRO/multimedia/lro-20100709-basin.html
http://curator.jsc.nasa.gov/lunar/letss/Regolith.pdf

Posted on by Nancy Atkinson

HiRISE Captures Amazing Close-Up of Spirit Rover

Spirit rover, as seen by HiRISE on Feb. 15, 2010. Crop and colorization by Stuart Atkinson, image credit: NASA/JPL, U of AZ

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The HiRISE team released some new images on Wednesday — one of which was another incredible avalanche image. But then there was another shot of Gusev Crater, the home of the Spirit rover. It was a wide shot of the entire region (you can see it below), and visible are the Columbia Hills, and if you look real close you can see the “Home Plate” region where Spirit sits. Our friend Stu Atkinson took a real close look and found Spirit sitting all alone –but very visible in this wonderfully amazing zoom-in closeup! (Click the image for access to a larger version). Stu also colorized it to show almost intricate detail of Spirit’s solar panels. The image was taken on Feb. 15, 2010, and she looks great! She’s in her current stationary position, and even though this image is from before she went into hibernation, it’s great to know she’s still sitting there, waiting for warmer days. “Hang in there rover, hang in there…” Stu said on Twitter, which echoes all our sentiments. Awww, Spirit….

Thanks to Stu and HiRISE for keeping our hopes alive!

The Spirit rover landing region. Credit: NASA/JPL/University of Arizona

Stu has also written a few of wonderful items about Spirit: A poem called Spirit Shivering, a great story about someone who maybe could travel to Mars and free Spirit, and a great blog post titled, “Spirit, Time to Rest.” Stu is a very talented writer and image editor, so check out his incredible handiwork!

Posted on by Nancy Atkinson

Hubble Captures Distorted Beauty of M66

M 66. Image credit: NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration. Acknowledgement: Davide De Martin and Robert Gendler

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This isn’t your basic spiral galaxy, but perhaps it used to be! Hubble’s Advanced Camera for Surveys has captured this beautiful view of the biggest child of the Leo Triplet, M66. Its asymmetric spiral arms and an apparently displaced core was mostly likely caused by the gravitational pull of the other two members of the trio. Talk about sibling rivalry!

M66, is located at a distance of about 35 million light-years in the constellation of Leo. Together with Messier 65 and NGC 3628, Messier 66 is one third of the Leo Triplet, a trio of interacting spiral galaxies, part of the larger Messier 66 group. While M66 is the biggest — it is about 100,000 light-years across — the gravitational influence from the two neighboring galaxies have distorted the one orderly spiral arms, making them appear to rise above the central core.

The striking dust lanes and bright star clusters along the spiral arm — pictured in the blue and pinkish regions of the image — are key tools for astronomers since they are used as indicators of how the parent galaxies assembled over time.

Messier 66 boasts a remarkable record of supernovae explosions. The spiral galaxy has hosted three supernovae since 1989, the latest one occurring in 2009. A supernova is a stellar explosion that may momentarily outshine its entire host galaxy. It then fades away over a period lasting several weeks or months. During its very short life the supernova radiates as much energy as the Sun would radiate over a period of about 10 billion years.

Source: European Hubble Space Telescope webpage

Posted on by Nancy Atkinson

Solar-Powered Airplane Makes Maiden Voyage

Solar Impulse durings its maiden voyage. Credit: Solar Impulse.


A solar powered airplane that one day will attempt an around the world non-stop flight took its maiden voyage yesterday in Switzerland. Solar Impulse flew for 87 minutes and climbed to 1,200 meters. “This first flight was for me a very intense moment!” exclaimed test pilot Markus Scherdel immediately after the flight. “The HB-SIA behaved just as the flight simulator told us! Despite its immense size and feather weight, the aircraft’s controllability matches our expectations!”

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“We reached all objectives, especially the safe landing, which was our main purpose,” said Claude Nicollier, a former astronaut who is one of the leaders of the project.

The plane has a 61 meter wingspan, and the wings are covered with 12,000 state-of-the-art photovoltaic solar cells that power the plane. Using so-called intelligent light materials and new energy storage, the plane will be able to fly both night and day, completely on solar power. Solar impulse weights 1,600 kg and can fly at speeds up to 70 kmh at a maximum altitude of 8,500 m (27 900 ft)

“We .still have a long way to go until the night flights and an even longer way before flying round the world, but today, thanks to the extraordinary work of an entire team, an essential step towards achieving our vision has been taken,” said Solar Impulse Chairman and initiator Bertrand Piccard. “Our future depends on our ability to convert rapidly to the use of renewable energies. Solar Impulse is intended to demonstrate what can be done already today by using these energies and applying new technologies that can save natural resources.”

For more information on Solar Impulse.

Posted on by Ken Kremer

Mother of Pearl Colored Clouds form above Kennedy after Discovery Blast Off

‘Mother of Pearl’ Colored Clouds form above the Countdown clock at the Kennedy Space Center Press Site about 23 minutes after the April 5, 2010 launch of Space Shuttle Discovery, as 3 excited Science Journalists point out (from left, Rob van Mackelenbergh, Jacob Kuiper and Ken Kremer). Credit: Jacob Kuiper

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(Editor’s Note: Ken Kremer is at the Kennedy Space Center for Universe Today covering the flight of Discovery)

Beautiful billowing clouds of all shapes, sizes and appearance always form from rocket exhaust plumes following a mighty rocket launch, whether it’s from the Space Shuttle or an unmanned rocket like the Atlas for the SDO launch (see my exhaust plume photo).

Well I’ve never witnessed anything like the magnificently colored clouds following Monday’s (April 5) predawn launch of Shuttle Discovery. They are known as “Mother of Pearl” clouds – according to Jacob Kuiper, Senior Meteorologist with the Royal Netherlands Meteorological Institute (KNMI).

Kuiper and myself observed the launch together with journalist Rob van Mackelenbergh (Dutch Society for Spaceflight, NVR) at the Kennedy Space Center (KSC) Press Site, located across the street from the iconic Vehicle Assembly Building where Shuttle’s are prepared for launch. See our STS 131 Launch day photo mosaic below of the day’s thrilling events.

At first the wispy clouds were nearly all white and set against the still dark sky. Then the sky overhead was suddenly lit on fire with a growing multitude of these pastel colored “Mother of Pearl” clouds – also called “Nacreous” clouds.

“The Mother of Pearl Clouds began turning from white to hues of pink and yellow. Starting about 10 minutes after the launch of Space Shuttle Discovery, its exhaust plume turned into a magnificently colorful panorama. Generally, this continues until about 40 minutes or more after blast off”, Kuiper told me as we stood next to the world famous Countdown clock and gazed in awe at the colored clouds above.

STS 131 Launch Day Mosaic: Crew walkout to Astro Van and ride to launch pad; Discovery Blast off and Countdown Clock at KSC Press site at T Plus 4 Seconds; Pastel Colored ‘Mother of Pearl’ Clouds which formed above the Countdown Clock at T Plus 23 Minutes as three science journalists are in awe. Click to Enlarge. Credit: Rob van Mackelenbergh, Ken Kremer and Jacob Kuiper

“Launching northeast in the predawn sky here on the ground means as the shuttle and its exhaust plumes head to orbit they’re going to catch the rising sunlight and that’s what creates the spectacular clouds we saw on launch morning !” KSC spokesman Allard Beutel explained to me.

Mother of Pearl Clouds form above US Flag at Kennedy Space Center from STS 131 Launch Exhaust Plume. Credit: Ken Kremer
The wispy clouds are transient events – constantly evolving in mere seconds as they are blown in a multitude of directions. Indeed it’s quite easy to let your imagination run wild and dream all sorts of fantastical things ranging from mythical creatures to assorted life forms and even people. Certainly someone has sighted Elvis in the rocket plumes.

“Atmospheric layers between 15 and 85 kilometers height normally contain very low quantities of water vapor. But the final exhaust product of the Shuttle’s external tank (hydrogen and oxygen) provides an enormous amount of water vapor”, Kuiper said.

“In the very cold atmosphere layers, the vapor turned into a tremendous mass of ice crystals and tiny super cooled water droplets. These crystals reflect and bend the solar rays very efficiently and create a nice spectrum of colors”.

“The lowest clouds, turned pink and orange, because at that height the sun just rises and most rays are a bit more reddish due to a certain extinction of the atmosphere. The higher portions of the exhaust plume hardly experience any extinction,” Kuiper explained.

Graphic of Nacreous clouds over Antartica. Atmospheric layers in the Antarctic winter. Nacreous clouds show colours similar to those on the inside of a Mother-of-Pearl shell. The clouds only occur at high polar latitudes in winter, requiring temperatures less than approximately -80ºC to form. Nacreous clouds also known as Mother-of-Pearl clouds, are rare cloud formations which are composed of ice crystals and form when temperatures are well below the ice frost point which is typically below -83C. The only place where these temperatures exist is in the stratosphere, some 20km (6 miles) above the surface. © Dr. Andrew Klekociuk, Australian Antarctic Division

“The yellow/white light of the sun – there a few more degrees above the horizon – is reflected immediately and causes the yellow and white, sometimes blueish colors. In the lowest segment of the atmospheric layers starting around 15 kilometers height, nature is able to form these clouds under very special circumstances. There they are called ‘Mother of Pearl’ clouds”.

“In layers around the Mesopause (about 85 km), clouds sometimes appear in the weeks around June 21 (northerly latitudes). These clouds are called Noctilucent clouds – or NLC. Both types can be produced due to the exhaust plumes from a Space Shuttle launch”, said Kuiper.

By far the largest and most long lasting rocket exhaust clouds derive from the Space Shuttle because it’s the most powerful rocket in the US Fleet – although not for much longer after the shuttle is retired and the US completely loses its Heavy Lift boost capability.

Internet sources: www.knmi.nl, www.weerboek.nl

Earlier STS 131 related articles by Ken Kremer:

Spectacular Radar Failed Belly Flip (Video) and Docking links Discovery to ISS

Antenna Glitch hinders Data Flow from Inspection of Discovery

Discovery Dazzles with Two Dawns in One Day

Discovery Unveiled on Easter Sunday to the Heavens Above

Countdown Clock Ticking for Discovery Blast off on April 5

Soyuz Blasts off with Russian American Crew for Easter ISS arrival

STS 131 Launch Contrails over the Kennedy Space Center on 5 April 2010. Credit: John O’Connor

Flock of Birds fly in front of Pastel colored clouds which formed above Kennedy Space Center from STS 131 Launch Exhaust Plume. Credit: Ken Kremer

Wispy contrails from the launch of space shuttle Discovery on the STS-131 mission glow in rainbow colors in the early morning hours as the sun rises over the Vehicle Assembly Building at NASA's Kennedy Space Center in Florida. Shuttle Discovery lifted off at 6:21 a.m. EDT on April 5, 2010. Credit: NASA/Kim Shiflett

Posted on by Nancy Atkinson

More Mars Avalanches from HiRISE, Oh My!

A shot monitoring the original site of active frost-dust avalanches (ESP_016173_2640) Credit: NASA/JPL/University of Arizona

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In 2008, the HiRISE camera on the Mars Reconnaissance Orbiter was monitoring a certain region on Mars for changes in frost patterns as spring progressed, and serendipitously captured an avalanche in action. This year, the HiRISE team has been on the lookout, ready to capture more avalanches as spring approaches in Mars’ northern hemisphere. They’ve been successful — and how! This awesome shot was captured on January 27, 2010 of a steep cliff in the northern polar region of Mars, and shows at least three isolated clouds of particles falling from the cliff. The HiRISE teams says that these clouds, rolling or hovering close to the ground likely reach up tens of meters high (up to 180 feet)! The avalanches are a result of carbon-dioxide frost that clings to the scarp in the darkness of winter, and when sunlight hits them in the spring they loosen up and fall. The cliff, approximately 700 meters (2000 feet) high is made up of layers of water ice with varying dust content, roughly similar to the polar ice caps on Earth. But wait, there’s more! Yes, it’s avalanche season on Mars!

Another avalanche seen earlier in 2010. Credit: NASA/JPL/University of Arizona

Here’s another avalanche captured on January 12, 2010, and below, the HiRISE camera was trained on the same site that the original avalanche was captured back in 2008.

A shot monitoring the original site of active frost-dust avalanches (ESP_016173_2640) Credit: NASA/JPL/University of Arizona

The HiRISE teams says that by looking at all of the individual instances of avalanches from all of the images will also allow them to piece together a sequence of snaphots of the whole avalanche process, from beginning (a stream of material falling down the cliff face) to end (lingering puffy clouds). Patrick Russell writes:

Based on this year’s observations, these events happen mostly in the middle of spring, roughly equivalent to April to early May on Earth. And, they are indeed more widespread than just this one scarp. All together, it seems this is a regular spring process at Mars’ north pole that may be expected every year – avalanche season! This information, in conjunction with the results of numerical modeling of the behavior of the materials involved, will help us find out what is causing these dramatic events.

For more wonderful images, check out the HiRISE website.