Sometimes I complain about the earthly weather, but mostly I like to post about astronomy and space events. Hope you enjoy the articles.
By: Susie77, 11:39 AM GMT on July 31, 2009
The Perseids are Coming
July 31, 2009: Earth is entering a stream of dusty debris from Comet Swift-Tuttle, the source of the annual Perseid meteor shower. Although the shower won't peak until August 11th and 12th, the show is already getting underway.
"I used an off-the-shelf digital camera to capture this fireball and its smoky trail," says Emfinger. "It was a bright one!"
Don't get too excited, cautions Bill Cooke of NASA's Meteoroid Environment Office. "We're just in the outskirts of the debris stream now. If you go out at night and stare at the sky, you'll probably only see a few Perseids per hour."
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This will change, however, as August unfolds.
"Earth passes through the densest part of the debris stream sometime on August 12th. Then, you could see dozens of meteors per hour."
For sky watchers in North America, the watch begins after nightfall on August 11th and continues until sunrise on the 12th. Veteran observers suggest the following strategy: Unfold a blanket on a flat patch of ground. (Note: The middle of your street is not a good choice.) Lie down and look up. Perseids can appear in any part of the sky, their tails all pointing back to the shower's radiant in the constellation Perseus. Get away from city lights if you can.
There is one light you cannot escape on August 12th. The 55% gibbous Moon will glare down from the constellation Aries just next door to the shower's radiant in Perseus. The Moon is beautiful, but don't stare at it. Bright moonlight ruins night vision and it will wipe out any faint Perseids in that part of the sky.
The Moon is least troublesome during the early evening hours of August 11th. Around 9 to 11 p.m. local time (your local time), both Perseus and the Moon will be hanging low in the north. This low profile reduces lunar glare while positioning the shower's radiant for a nice display of Earthgrazers.
"Earthgrazers are meteors that approach from the horizon and skim the atmosphere overhead like a stone skipping across the surface of a pond," explains Cooke. "They are long, slow and colorful—among the most beautiful of meteors." He notes that an hour of watching may net only a few of these at most, but seeing even one can make the whole night worthwhile.
The Perseids are coming. Enjoy the show.
By: Susie77, 9:52 PM GMT on July 25, 2009
So I heard a rumor the other day that this July may go down in the record books as the Midwest's 5th-coolest July. Anyone know if this is true, and what theories account for it? Thanks!
(I was wondering if we should thank that volcano in Siberia.)
By: Susie77, 7:19 PM GMT on July 23, 2009
Scramjets promise space travel for all
* 22 July 2009 by Greg Klerkx
* Magazine issue 2718. Subscribe and get 4 free issues.
* For similar stories, visit the Galleries and Spaceflight Topic Guides
Gallery: Spaceplanes and scramjets: A 50-year history
ON A bright autumn morning five years ago, the space-flight community was turned on its head by a little teardrop-shaped spacecraft built in a small workshop in California's Mojave desert. The successful flight of SpaceShipOne on 29 September 2004, the first of two flights en route to winning the $10 million Ansari X prize, seemed to usher in a new era of space travel - one in which space flight would be affordable, frequent and, perhaps most importantly, accessible to all.
SpaceShipOne was the first crewed spacecraft to be developed privately. Designed, built and flown on a budget of roughly $25 million, it was much cheaper than the multibillion-dollar US government-backed space shuttle. In its climb to just over 111 kilometres above the Earth, SpaceShipOne broke the world altitude record for a winged vehicle, set more than 40 years earlier by NASA's
X-15 rocket plane. It was also fully reusable, a feature long seen as an essential milestone on the path to a more accessible spacefaring future.
And yet, five years on, it is easy to regard SpaceShipOne as more anomaly than herald. After making two sub-orbital flights in two weeks, it never flew again: the craft now hangs in the Smithsonian National Air and Space Museum in Washington DC. The Spaceship Company, a partnership between SpaceShipOne creator Burt Rutan and airline tycoon Richard Branson has yet to unveil the larger, passenger-ready SpaceShipTwo, although the company has revealed the carrier aircraft needed to launch it on its way to space. Most other commercial space-flight projects remain on the ground.
"I think Burt Rutan did a great thing with SpaceShipOne," says Elon Musk, CEO and chief designer at commercial space company SpaceX.
"However, it is important to appreciate that it is only a Mach 3 [three times the speed of sound] terminal velocity vehicle. You need Mach 25 to reach low Earth orbit, and the energy required scales with the square of the velocity."
Whatever its limitations as a spacecraft, SpaceShipOne has galvanised attempts to break the "space access" problem. There are arguably more spacecraft development efforts under way now than at any point in the brief history of space flight. So which idea, or set of ideas, will produce the breakthrough vehicle? "To achieve a true revolution in cost and reliability, we have to make a truly reusable system," Musk says. "That's one of the biggest technical challenges known to man."
This challenge is gradually yielding to human ingenuity. SpaceX has successfully flown its Falcon rocket, after several aborted attempts, and other companies are doing ever more advanced tests on new engines, systems and designs. And one long-awaited test flight later this year may herald a major technological breakthrough in air-breathing engines that could power a winged vehicle from runway to orbit, ultimately fulfilling the dream that SpaceShipOne has rekindled.
Space vehicles can be broadly divided into two categories: those inspired by winged aircraft and those inspired by ballistic rockets.
In the early days of the space race, winged and ballistic craft were both considered to be viable options for reaching orbit. Yet they represent vastly different ideas about space travel, in terms of both engineering and economics. Ballistic spacecraft simply pile in the fuel and use brute force to push their way into space, shedding engines and fuel tanks on their way up to lighten the load.
Winged spacecraft are the more elegant option. Launching from the ground or from the back or belly of another aircraft, they use the Earth's atmosphere for lift as long as possible. On the way back, they glide down to Earth to be used again and again. Their potential reusability has led to the tantalising idea that winged spacecraft could, in time, be much cheaper to operate than ballistic throwaways.
They could even use the same facilities as commercial airliners, opening up space travel to commerce and even tourism.
In reality, winged spacecraft like SpaceShipOne and NASA's X-15 - which reached an altitude of 107 kilometres - have never made it past the lower reaches of space. Their on-board rocket engines lacked the oomph to propel them the extra 60 kilometres or so needed to reach orbit. The conspicuous exception to this rule is the space shuttle, a vehicle that was part winged spacecraft and part ballistic vehicle.
The shuttle isn't completely reusable, however: on each flight the expensive external fuel tank is dumped in the ocean. Yet it showcases the most important technologies for low-cost, reliable access to space, says Daniel Rasky, a NASA scientist who has developed flight hardware for several of the agency's spacecraft. "The key is reusability, combined with flying often," he says. "Where the shuttle falls down is the 'flying often' part."
Originally designed to fly hundreds of times annually and therefore reduce the cost of each flight, the shuttle fleet has never managed more than nine flights in a year. Lessons from the shuttle are being incorporated into NASA's Constellation Program, the project to design the shuttle's replacement, with the ultimate aim of sending people back to the moon. But while some elements of Constellation's spacecraft are designed to be reusable, Rasky believes that the design is a step back towards the Apollo era. "It can probably be made reliable enough, but it will never be low-cost because it will never be flown enough."
This is where commercial space companies come in. A new NASA initiative led by Rasky, called Space Portal, is forging partnerships between the agency and new space companies, with a focus on breaking the cheap-space-flight barrier. In the past year, for example, Space Portal has helped SpaceX develop high-performance heat shielding by, amongst other things, providing the company with the means to manufacture the material in-house.
Advanced technology is also breathing fresh life into winged spacecraft. The buzz centres on a hypersonic engine known as a supersonic combustion ramjet, or scramjet. Despite the name, scramjets are very different to the turbojet engines that power commercial aircraft, not least because scramjet-powered vehicles must first be accelerated to Mach 4 or so using jet engines or rockets before their scramjets can work. This is because, unlike turbojets, scramjets do not use spinning blades to compress the air entering the engine.
Instead, the high speed of the vehicle compresses the incoming air, which is then fed into a combustion chamber where the burning fuel creates an exhaust jetthat exits the engine faster than the air that entered (see diagram).
Advanced technology is beginning to breathe fresh life into winged spacecraft
Scramjets only work when travelling at high speeds - and getting them there requires complicated technology and lots of fuel. This has led some critics to liken scramjets to nuclear fusion reactors: a great idea but technically impractical. The first tests, in the 1990s, weren't promising - the scramjets required far more energy than they produced. Overcoming these problems is expensive, which until recently ruled out the scramjet for anything other than military applications.
Yet the first successful scramjet flight was delivered on a relatively modest budget of $1.1 million. It took place in 2002, when a joint British and Australian team flew their HyShot vehicle at the Woomera range in South Australia. To keep costs down, the scramjet was mounted on the nose of a conventional rocket. HyShot reached Mach 7.6, about 9000 kilometres per hour, for several seconds before breaking up.
Since then, scramjet development and testing has accelerated markedly, culminating in 2004 with NASA's X-43A scramjet aircraft, which flew at Mach 9.68 - a new world record for jet-powered travel. In the last few years, news of other scramjet research has trickled out, including programmes in Japan, Russia and China, as well as an Indian plan to develop a hypersonic spaceplane called Avatar.
Later this year, a consortium that includes NASA, the US air force and the Defense Advanced Research Projects Agency (DARPA) plans to fly a more advanced scramjet vehicle, the X-51A, over the Pacific Ocean. The programme's aim is to demonstrate that the small prototype engine can be scaled up. Designed to operate between Mach 4 and 6, the X-51A will also test a range of new materials that could, if successful, allow scramjets to operate for longer than the mere seconds that previous test vehicles lasted.
Critically, scramjet programmes like the X-51A are working towards reusability. This has proven elusive so far: all scramjet test vehicles have been intentionally destroyed after their brief period of use, largely because they burn out. The obstacles to greater scramjet robustness are many. Top of the list is keeping air moving through the engine at sufficient speeds for combustion, as well as preventing the engine from melting. Even with these problems, NASA is sufficiently encouraged by recent progress to have established several national science centres earlier this year. These will explore, and eventually exploit, scramjet technology.
Results from the X-51A programme may help another style of engine being designed by DARPA. Called Vulcan, it will be capable of launching a craft from a runway like a commercial airliner before accelerating it to hypersonic speeds. To do this, Vulcan will use a modified turbojet engine to accelerate to around Mach 2, at which point its hypersonic engine - possibly based on a pulse detonation design first used in Germany's V-1 flying bomb during the second world war - would kick in to push it beyond Mach 4. Both units would be integrated into an airframe similar to the X-51A. DARPA hopes to produce a test vehicle by 2012. Though it is initially aimed at military applications, the organisation suggests that future versions of the vehicle could allow for runway-based access to space.
So will these scramjets reach orbit unaided? Estimates for their top speed range from Mach 12 to Mach 20 - still short of the Mach 25 or so needed to propel them into orbit. To get round this problem, rockets will have to play a role on a scramjet-powered spaceplane, either as initial accelerants or final-stage boosters. This shouldn't affect their reusability too much, though, as most of the space vehicles'
power will come from the scramjet engine, making them far more reusable than the space shuttle. And because they are designed to draw oxidiser from very thin air, they would be much lighter than conventional ballistic vehicles. On the space shuttle, for instance, oxidiser accounts for about 85 per cent of the contents of the external fuel tanks.
Yet the debate over hypersonic-powered spacecraft is as contentious as that over winged versus ballistic vehicles. Critics of the hypersonic approach say that even if the technology does become viable, it is likely to remain in the military-industrial realm for some time to come, mainly due to expense. "Obviously, there are military applications for fast transport of small teams to a critical area,"
says Derek Webber of Spaceport Associates, which has conducted a market analysis for future space activities. The civilian equivalent, a hypersonic airliner, could take super-rich travellers right round the globe in just 4 hours.
Some engineers believe there is a third way forward: a relatively inexpensive, reusable winged spacecraft that does not rely on experimental technology such as scramjets or throwaway ballistic systems. British company Reaction Engines falls into this category:
its proposed Skylon vehicle would use an advanced air-breathing engine called Sabre to reach orbit.
At high speed, air entering an engine is compressed so fast that it heats up rapidly - that is why scramjets must be built using special, hefty heat-resistant alloys. To combat this, Skylon's jet engine would use a heat exchanger to cool incoming air from around 1000°C to less than -100 °C. The cooled air is then mixed with liquid hydrogen and burned. As a result, the Sabre will be lighter and, unlike a scramjet, it should work from launch up to a speed of Mach 5.5. Then, at an altitude of 26 kilometres, the engine would switch to normal rocket power and use on-board oxygen and hydrogen to propel the plane into space.
The Skylon is a return to the classic spaceplane dream. Launching under its own power, the unpiloted Skylon would fly into orbit, deliver its payload, and land on a runway. "Making launchers operate like civil aircraft is the route to unblocking the metaphoric dam,"
said Mark Hempsell, future programmes director for Reaction Engines.
The Skylon is a return to the classic spaceplane dream: launching under its own power, flying into orbit and landing on a runway
Skylon and its Sabre engine are new versions of work done by British Aerospace and Rolls-Royce in the 1980s, thereby continuing the trend in spacecraft development of building upon previously developed systems, rather than starting from scratch. Crucially, Reaction Engines does not propose to manufacture the Skylon nor the Sabre, but rather to contract those activities to aerospace firms with the facilities and experience to do so.
As the strategy of Reaction Engines suggests, smaller companies are recognising that they need the big players - and the results of their heavily funded research - to have any chance of achieving a true breakthrough. Likewise, Rasky and others at NASA now view space entrepreneurs as partners, not competitors. Another Space Portal programme, for example, would send science experiments on sub-orbital vehicles produced by companies such as Virgin Galactic, Mojave-based XCOR Aerospace, and Blue Origin in Kent, Washington. NASA would pay for the flights like any commercial customer, giving these companies a market for their services. And NASA is already funding a number of entrepreneurs, including SpaceX, through its Commercial Orbital Transport Services programme, which seeks to find cheaper, more reliable orbital space transport.
"Today's emerging commercial space offerings stand a much better chance of success because they're attacking the real issues," Rasky says, including purely commercial challenges such as focusing on expanding a customer base. "New and advanced technology will play an important role, but it will be evolutionary, similar to how technology impacts other forms of transportation, like cars and airplanes."
In this light, the success of SpaceShipOne created one undeniable result. As Hempsell points out: "It took away the giggle factor." In the short and often fractious history of space flight, that's one giant step towards a different, and perhaps more exciting, spacefaring future.
By: Susie77, 10:37 PM GMT on July 22, 2009
(And solar eclipse photo gallery)
Space Weather News for July 22, 2009
AURORA SURPRISE: Last night, July 21st and 22nd, a solar wind stream hit Earth's magnetic field and surprised observers with an unexpected display of auroras. Northern Lights swept across parts of Canada and descended as far south as the Dakotas, Montana, Iowa and Wisconsin in the United States. Photos of the display are featured on today's edition of http://spaceweather.com .
AURORA ALERTS: Did you sleep through the show? Next time get a wake up call from Space Weather PHONE: http://spaceweatherphone.com.
JULY 22nd SOLAR ECLIPSE GALLERY: The longest solar eclipse of the 21st century is over and, despite a disappointing rainstorm over Shanghai, millions of people witnessed the event. Highlights may be found in our eclipse gallery. Start browsing here: http://spaceweather.com/eclipses/gallery_22jul09_page3.htm
By: Susie77, 10:14 PM GMT on July 21, 2009
Space Weather News for July 21, 2009
SOLAR ECLIPSE: The longest total eclipse of the 21st century is about to begin. It starts just hours from now at approximately 9 p.m. EDT on July 21st (0100 UT on July 22nd). The path of totality crosses many major cities in India and China, setting the stage for possibly the best-observed eclipse in history. Photos from the path of totality will be posted on http://spaceweather.com as the event unfolds.
COSMIC COLLISION: Evidence is mounting that something did hit Jupiter no more than a few days ago. The impact site (a dark "scar" in Jupiter's clouds) was discovered on July 19th by Australian amateur astronomer Anthony Wesley, and NASA astronomers quickly confirmed the find. Infrared photos posted on today's edition of Spaceweather.com are consistent with an asteroid or comet strike on the giant planet. The debris zone in Jupiter's clouds is itself as wide as a small planet, making it an easy target for backyard telescopes.
By: Susie77, 1:28 AM GMT on July 21, 2009
Longest Solar Eclipse of the 21st Century
July 20, 2009: One one-thousand, 2 one-thousand, 3 one-thousand, 4 one-thousand...
Continue counting and don't stop until you reach 399 one-thousand.
Did that feel like a long time? Six minutes and 39 seconds to be exact. That's the duration of this week's total solar eclipse--the longest of the 21st century.
The event begins at the crack of dawn on Wednesday, July 22nd, in the Gulf of Khambhat just east of India. Morning fishermen will experience a sunrise like nothing they've ever seen before. Rising out of the waves in place of the usual sun will be an inky-black hole surrounded by pale streamers splayed across the sky. Sea birds will stop squawking, unsure if the day is beginning or not, as a strange shadow pushes back the dawn and stirs up a breeze of unaccustomed chill.
Most solar eclipses produce this sort of surreal experience for a few minutes at most. The eclipse of July 22, 2009, however, will last as long as 6 minutes and 39 seconds in some places, not far short of the 7 and a half minute theoretical maximum. It won't be surpassed in duration until the eclipse of June 13, 2132.
From the Gulf of Khambhat, the Moon's shadow will race east across India, China, and the Ryukyu Islands of Japan.
The path of totality cuts across many large cities. The shadow will linger over Shanghai, the largest city in China, for six full minutes, giving 20 million residents a lengthy and stunning view of the sun's ghostly corona. Other large cities in the path of totality include Surat, Vadodara, Bhopal, Varanasi, Chengdu, Chongqing, Wuhan, Hefei, Hangzhou. The population of each numbers in the millions, making this possibly the best-observed solar eclipse in human history.
The eclipse is extra-long because of a lucky coincidence, made possible by the elliptical shape of planetary orbits. On July 22nd, Earth happens to be near its farthest point from the sun. A small sun means the Moon can cover it longer. At the same time, the Moon will be near its closest point to Earth. A large Moon covers the sun longer, lengthening the eclipse even more.
The leisurely pace of the eclipse could have a transformative effect on witnesses. Total eclipses have been known to turn ordinary folk into life-long "eclipse-chasers" willing to spend thousands of dollars and travel tens of thousands of miles to feel the Moon's cool shadow and behold the sun's pale atmosphere just one more time. A few extra minutes of wonder will intensify this effect to an unknown degree.
Live webcasts of the eclipse--not the next best thing to being there, but the only substitute available to many readers--may be found at the website of the San Francisco Exploratorium.
Let the counting begin.
By: Susie77, 1:54 AM GMT on July 20, 2009
Space Weather News For July 19, 2009
JUPITER IMPACT? On July 19th, a veteran observer of Jupiter in Australia photographed a fresh dark "scar" in Jupiter's cloudtops; the feature resembles the Shoemaker-Levy 9 impacts of 1994. It is possible that Jupiter has been struck anew by an asteroid or comet. Astrophotographers around the world should train their optics on Jupiter to confirm the event and monitor its progress. Visit http://spaceweather.com for photos and updates.
By: Susie77, 2:44 AM GMT on July 18, 2009
July 17, 2009
NASA MOURNS THE DEATH OF WALTER CRONKITE
WASHINGTON --The following is a statement from NASA Administrator
Charles Bolden on the death of veteran journalist Walter Cronkite.
"It is with great sadness that the NASA family learned of Walter
Cronkite's passing. He led the transition from print and radio
reporting to the juggernaut that became television journalism. His
insight and integrity were unparalleled, and his compassion helped
America make it through some of the most tragic and trying times of
the 20th century.
"From the earliest days of the space program, Walter brought the
excitement, the drama and the achievements of space flight directly
into our homes. But it was the conquest of the moon in the late 1960s
that energized Walter most about exploration. He called it the most
important feat of all time and said that the success of Apollo 11
would be remembered 500 years from now as humanity's greatest
"It was Walter Cronkite's impassioned reporting on America's inaugural
moon landing that inspired me to join in the dreams of many to travel
to space and accept the risks that this exploration brings while I
was a student in naval flight training.
"In honor of his ethical and enthusiastic coverage of our nations'
space program, NASA was proud to honor Walter in 2006 with an
Ambassador of Exploration Award and presented him with an Apollo
"For decades, we had the privilege of learning about our world from
the original 'anchorman.' He was a true gentleman. Our thoughts and
prayers are with Walter's family and his millions of friends and
By: Susie77, 12:45 AM GMT on July 16, 2009
(anyone remember the Jethro Tull song about the moon landing?)
July 15, 2009
STATEMENT FROM APOLLO 11 ASTRONAUT MICHAEL COLLINS
The following is a series of questions and answers prepared by Michael
Collins, command module pilot for Apollo 11. Collins issued the
following statement in lieu of media interviews:
These are questions I am most frequently asked, plus a few others I
have added. For more information, please consult my book, the 40th
anniversary edition of CARRYING THE FIRE, published by Farrar, Straus
& Giroux. All of the following sections in quotation marks are from
Q. Circling the lonely moon by yourself, the loneliest person in the
universe, weren't you lonely?
"Far from feeling lonely or abandoned, I feel very much a part of what
is taking place on the lunar surface. I know that I would be a liar
or a fool if I said that I have the best of the three Apollo 11
seats, but I can say with truth and equanimity that I am perfectly
satisfied with the one I have. This venture has been structured for
three men, and I consider my third to be as necessary as either of
the other two. I don't mean to deny a feeling of solitude. It is
there, reinforced by the fact that radio contact with the Earth
abruptly cuts off at the instant I disappear behind the moon, I am
alone now, truly alone, and absolutely isolated from any known life.
I am it. If a count were taken, the score would be three billion plus
two over on the other side of the moon, and one plus God knows what
on this side."
Q. Did you have the best seat on Apollo 11?
"The cancellation of 014 also freed Borman-Stafford-Collins for
reassignment, and reassigned we were, but not as a unit. Tom Stafford
moved up a notch and acquired his own highly experienced crew, John
Young and Gene Cernan; they became McDivitt's back-up. Score one for
Tom. Borman and Collins got promoted to prime crew of the third
manned flight, picking up Bill Anders as our third member.
In the process, Collins also got 'promoted' from lunar module pilot to
command module pilot, and lost right then and there his first chance
to walk on the surface of the moon. The reason I had to move up was
that Deke at that time had a firm rule that the command module pilot
on all flights involving LM must have flown before in space, the idea
being that he didn't want any rookie in the CM by himself. Since Bill
and Anders had not flown, I was it. Slowly it sunk in. No LM for me,
no EVA, no fancy flying, no need to practice in helicopters anymore."
Q. Were you happy with the seat you had?
A. Yes, absolutely. It was an honor.
Q. Has the space program helped young people become interested in
careers in math and science? Don't you tell kids to opt for these
A. Yes and no. We definitely have a national problem in that kids seem
to be going for money rather than what they consider 'nerdy' careers.
Other countries are outstripping us in the quality and quantity of
math and science grads, and this can only hurt in the long run. But a
liberal arts education, particularly English, is a good entry point
no matter what the later specialization. I usually talk up English.
Q. Turning to your flight, what is your strongest memory of Apollo 11?
A. Looking back at Earth from a great distance.
"I really believe that if the political leaders of the world could see
their planet from a distance of 100,000 miles their outlook could be
fundamentally changed. That all-important border would be invisible,
that noisy argument silenced. The tiny globe would continue to turn,
serenely ignoring its subdivisions, presenting a unified fa?ade that
would cry out for unified understanding, for homogeneous treatment.
The earth must become as it appears: blue and white, not capitalist
or Communist; blue and white, not rich or poor; blue and white, not
envious or envied."
Small, shiny, serene, blue and white, FRAGILE.
Q. That was 40 years ago. Would it look the same today?
A. Yes, from the moon, but appearances can be deceiving. It's
certainly not serene, but definitely fragile, and growing more so.
When we flew to the moon, our population was 3 billion; today it has
more than doubled and is headed for 8 billion, the experts say. I do
not think this growth is sustainable or healthy. The loss of habitat,
the trashing of oceans, the accumulation of waste products - this is
no way to treat a planet.
Q. You are starting to sound a little grumpy. Are you grumpy?
A. At age 78, yes, in many ways. Some things about current society
irritate me, such as the adulation of celebrities and the inflation
Q. But aren't you both?
A. Not me. Neither.
Heroes abound, and should be revered as such, but don't count
astronauts among them. We work very hard; we did our jobs to near
perfection, but that was what we had hired on to do. In no way did we
meet the criterion of the Congressional Medal of Honor: 'above and
beyond the call of duty.'
Celebrities? What nonsense, what an empty concept for a person to be,
as my friend the great historian Daniel Boorstin put it, "known for
his well-known-ness." How many live-ins, how many trips to rehab,
maybe--wow--you could even get arrested and then you would really be
noticed. Don't get me started.
Q. So, if I wanted to sum you up, I should say "grumpy?"
A. No, no, lucky! Usually, you find yourself either too young or too
old to do what you really want, but consider: Neil Armstrong was born
in 1930, Buzz Aldrin 1930, and Mike Collins 1930. We came along at
exactly the right time. We survived hazardous careers and we were
successful in them. But in my own case at least, it was 10 percent
shrewd planning and 90 percent blind luck. Put LUCKY on my tombstone.
Q. Okay, but getting back to the space program. What's next?
A. I hope Mars. It was my favorite planet as a kid and still is. As
celestial bodies go, the moon is not a particularly interesting
place, but Mars is. It is the closest thing to a sister planet that
we have found so far. I worry that at NASA's creeping pace, with the
emphasis on returning to the moon, Mars may be receding into the
distance. That's about all I have to say.
Q. I understand you have become a recluse.
A. I'm not sure that's the word. I think of the Brown Recluse, the
deadliest of spiders, and I have a suntan, so perhaps. Anyway, it's
true I've never enjoyed the spotlight, don't know why, maybe it ties
in with the celebrity thing.
Q. So, how do you spend your time?
A. Running, biking, swimming, fishing, painting, cooking, reading,
worrying about the stock market, searching for a really good bottle
of cabernet under ten dollars. Moderately busy.
Q. No TV?
A. A few nature programs, and the Washington Redskins, that's about
Q. Do you feel you've gotten enough recognition for your
A. Lordy, yes, Oodles and oodles.
Q. Oodles?? But don't you have any keen insights?
A. Oh yeah, a whole bunch, but I'm saving them for the 50th.
Collins's official NASA astronaut biography is available online at:
Additional information about the 40th anniversary of Apollo can be
By: Susie77, 12:33 AM GMT on July 16, 2009
Can you believe that it has been 40 years ago, this month? What a year was 1969. Where were you?
APOLLO 11 CONVERSATIONS EARTH DIDN'T HEAR NOW ONLINE AT NASA.GOV
HOUSTON -- You're in a spacecraft, on a mission to land on the moon
for the first time in history, and the microphone to Earth is off.
What do you say?
Now you can listen in on a NASA Web site and find out.
As Neil Armstrong, Buzz Aldrin and Mike Collins flew on Apollo 11 to a
lunar landing in July 1969, the world heard communications between
the crew and Mission Control live as they happened. But Earth did not
hear the private conversations between Armstrong, Aldrin and Collins,
although they were recorded aboard the Command Module Columbia and
Lunar Module Eagle.
Those conversations now are available on the Internet. All the Apollo
spacecraft had onboard voice recorders, activated during much of each
mission to record the crew's conversations. The transcripts of those
recordings were publicly released in the mid-1970s. Only recently
were the actual onboard audio recordings from Apollo 11 digitized and
made available on the Web.
To listen to the recordings and view the transcript, visit:
For more information about the history of onboard recorders on the
Apollo spacecraft and full transcripts of all mission recordings,
For a detailed list of NASA events that celebrate the 40th anniversary
of Apollo 11, visit:
By: Susie77, 12:37 AM GMT on July 15, 2009
What a lovely, lovely evening. Many folks here are focused on and/or attending the All Star game in St. Louis. Me, just sitting on my deck with a glass of wine. Admiring how green and lush are the grass and trees and gardens... unusual here for mid July. It's only 79 degrees out, light breeze, overcast skies.
A nice night for either a ball game, or just to be outdoors! What a lovely gift for this time of year, here in the hot n steamy midsection of the country.
By: Susie77, 5:05 PM GMT on July 14, 2009
Nothing much happening with the sun lately in this, one of the deepest solar minimums recorded. However, the night skies still have some beautiful sights:
Noctilucent Cloud Gallery
By: Susie77, 12:29 AM GMT on July 10, 2009
Usually I'll post the entire article, but it's hot, I'm crabby, I hate summer, I hate a/c, I hate not being outdoors, the a/c was broken again at work today.... blah blah. So if you're interested, just check out the link. Sorry. I promise to be cheerier come fall.
NASA Science News for July 9, 2009
Amateur astronomers have photographed NASA's LCROSS spacecraft en route to an October crash landing on the Moon. Observers say the spacecraft is surprisingly easy to photograph, and NASA hopes more amateurs will give it a try.
FULL STORY at
By: Susie77, 11:21 AM GMT on July 03, 2009
NASA'S FERMI TELESCOPE PROBES DOZENS OF PULSARS
WASHINGTON -- With NASA's Fermi Gamma-ray Space Telescope, astronomers
now are getting their best look at those whirling stellar cinders
known as pulsars. In two studies published in the July 2 edition of
Science Express, international teams have analyzed gamma-rays from
two dozen pulsars, including 16 discovered by Fermi. Fermi is the
first spacecraft able to identify pulsars by their gamma-ray emission
A pulsar is the rapidly spinning and highly magnetized core left
behind when a massive star explodes. Most of the 1,800 cataloged
pulsars were found through their periodic radio emissions.
Astronomers believe these pulses are caused by narrow,
lighthouse-like radio beams emanating from the pulsar's magnetic
"Fermi has truly unprecedented power for discovering and studying
gamma-ray pulsars," said Paul Ray of the Naval Research Laboratory in
Washington. "Since the demise of the Compton Gamma Ray Observatory a
decade ago, we've wondered about the nature of unidentified gamma-ray
sources it detected in our galaxy. These studies from Fermi lift the
veil on many of them."
The Vela pulsar, which spins 11 times a second, is the brightest
persistent source of gamma rays in the sky. Yet gamma rays -- the
most energetic form of light -- are few and far between. Even Fermi's
Large Area Telescope sees only about one gamma-ray photon from Vela
every two minutes.
"That's about one photon for every thousand Vela rotations," said
Marcus Ziegler, a member of the team reporting on the new pulsars at
the University of California, Santa Cruz. "From the faintest pulsar
we studied, we see only two gamma-ray photons a day."
Radio telescopes on Earth can detect a pulsar easily only if one of
the narrow radio beams happens to swing our way. If not, the pulsar
can remain hidden.
A pulsar's radio beams represent only a few parts per million of its
total power, whereas its gamma rays account for 10 percent or more.
Somehow, pulsars are able to accelerate particles to speeds near that
of light. These particles emit a broad beam of gamma rays as they arc
along curved magnetic field lines.
The new pulsars were discovered as part of a comprehensive search for
periodic gamma-ray fluctuations using five months of Fermi Large Area
Telescope data and new computational techniques.
"Before launch, some predicted Fermi might uncover a handful of new
pulsars during its mission," Ziegler added. "To discover 16 in its
first five months of operation is really beyond our wildest dreams."
Like spinning tops, pulsars slow down as they lose energy. Eventually,
they spin too slowly to power their characteristic emissions and
But pair a slowed dormant pulsar with a normal star, and a stream of
stellar matter from the companion can spill onto the pulsar and
increase its spin. At rotation periods between 100 and 1,000 times a
second, ancient pulsars can resume the activity of their youth. In
the second study, Fermi scientists examined gamma rays from eight of
these "born-again" pulsars, all of which were previously discovered
at radio wavelengths.
"Before Fermi launched, it wasn't clear that pulsars with millisecond
periods could emit gamma rays at all," said Lucas Guillemot at the
Center for Nuclear Studies in Gradignan, near Bordeaux, France. "Now
we know they do. It's also clear that, despite their differences,
both normal and millisecond pulsars share similar mechanisms for
emitting gamma rays."
NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle
physics partnership, developed in collaboration with the U.S.
Department of Energy, along with important contributions from
academic institutions and partners in France, Germany, Italy, Japan,
Sweden, and the U.S.
For more information about Fermi, visit:
For images related to this release, visit:
By: Susie77, 6:43 PM GMT on July 01, 2009
Sea level rise: It's worse than we thought
* 01 July 2009 by Anil Ananthaswamy
FOR a few minutes David Holland forgets about his work and screams like a kid on a roller coaster. The small helicopter he's riding in is slaloming between towering cliffs of ice - the sheer sides of gigantic icebergs that had calved off Greenland's Jakobshavn glacier. "It was like in a James Bond movie," Holland says afterwards. "It's the most exciting thing I have ever done."
Jakobshavn has doubled its speed in the past 15 years, draining increasing amounts of ice from the Greenland ice sheet into the ocean, and Holland, an oceanographer at New York University, has been trying to find out why. Scientists like him are more than a little astonished at the rate at which our planet's frozen frontiers seem to be responding to global warming. The crucial question, though, is what will happen over the next few decades and centuries.
That's because the fate of the planet's ice, from relatively small ice caps in places like the Canadian Arctic, the Andes and the Himalayas, to the immense ice sheets of Greenland and Antarctica, will largely determine the speed and extent of sea level rise. At stake are the lives and livelihoods of hundreds of millions of people, not to mention millions of square kilometres of cities and coastal land, and trillions of dollars in economic terms.
In its 2007 report, the Intergovernmental Panel on Climate Change (IPCC) forecast a sea level rise of between 19 and 59 centimetres by 2100, but this excluded "future rapid dynamical changes in ice flow". Crudely speaking, these estimates assume ice sheets are a bit like vast ice cubes sitting on a flat surface, which will stay in place as they slowly melt. But what if some ice sheets are more like ice cubes sitting on an upside-down bowl, which could suddenly slide off into the sea as conditions get slippery? "Larger rises cannot be excluded but understanding of these effects is too limited to assess their likelihood," the IPCC report stated.
Even before it was released, the report was outdated. Researchers now know far more. And while we still don't understand the dynamics of ice sheets and glaciers well enough to make precise predictions, we are narrowing down the possibilities. The good news is that some of the scarier scenarios, such as a sudden collapse of the Greenland ice sheet, now appear less likely. The bad news is that there is a growing consensus that the IPCC estimates are wildly optimistic.
The oceans are already rising. Global average sea level rose about 17 centimetres in the 20th century, and the rate of rise is increasing. The biggest uncertainty for those trying to predict future changes is how humanity will behave. Will we start to curb our emissions of greenhouse gases sometime soon, or will we continue to pump ever more into the atmosphere?
Even if all emissions stopped today, sea level would continue to rise. "The current rate of rise would continue for centuries if temperatures are constant, and that would add about 30 centimetres per century to global sea level," says Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research in Germany. "If we burn all fossil fuels, we are likely to end up with many metres of sea level rise in the long run, very likely more than 10 metres in my view."
This might sound dramatic, but we know sea level has swung from 120 metres lower than today during ice ages to more than 70 metres higher during hot periods. There is no doubt at all that if the planet warms, the sea will rise. The key questions are, by how much and how soon?
To pin down the possibilities, researchers have to look at what will happen to all the different contributors to sea level under various emissions scenarios. The single biggest contributor to sea level rise over the past century has been the melting of glaciers and ice caps outside of Greenland and Antarctica, from Alaska to the Himalayas. According to one recent estimate, the continued loss of this ice will add another 10 to 20 centimetres to sea level by 2100. It cannot get much worse than this: even if all this ice melted, sea level would only rise by about 33 centimetres.
The second biggest contributor has been thermal expansion of the oceans. Its future contribution is relatively simple to predict, as we know exactly how much water expands for a given increase in temperature. A study published earlier this year found that even if all emissions stopped once carbon dioxide levels hit 450 parts per million (ppm) - an unrealistically optimistic scenario - thermal expansion alone would cause sea level to rise by 20 centimetres by 2100, and by another 10 centimetres by 3000. At the other extreme, if emissions peak at 1200 ppm, thermal expansion alone would lead to a 0.5-metre rise by 2100, and another 1.4 metres by 3000 (see "How high, how soon?").
Then there are the great ice sheets of Greenland and Antarctica, which hold enough water to raise sea level by about 70 metres. Until recently, their contribution to sea level rise was negligible, and the IPCC predicted that Greenland would contribute 12 centimetres at most to sea level rise by 2100, while Antarctica would actually gain ice overall due to increased snowfall. "A lot of new results have been published since then to show that this very conservative conclusion does not hold," says Eric Rignot of the University of California, Irvine.
To study the ice sheets, Rignot and colleagues have combined satellite-based radar surveys, aircraft altimetry and gravity measurements using NASA's GRACE satellite. They found that ice loss is increasing fast. Greenland is now losing about 300 gigatonnes of ice per year, enough to raise sea level by 0.83 millimetres. Antarctica is losing about 200 gigatonnes per year, almost all of it from West Antarctica and the Antarctic Peninsula, raising levels by 0.55 millimetres. "The mass loss is increasing faster than in Greenland," Rignot says. "It'll overtake Greenland in years to come."
If this trend continues, Rignot thinks sea level rise will exceed 1 metre by 2100. So understanding why Greenland and Antarctica are already losing ice faster than predicted is crucial to improving our predictions.
The main reason for the increase is the speeding up of glaciers that drain the ice sheets into the sea. One cause is the knock-on effect of warmer air melting the surface of the ice: when the surface ice melts, the water pours down through crevasses and moulins to the base of glaciers, lubricating their descent into the sea. Fears about the impact of this phenomenon have receded somewhat, though: Antarctica is thought to be too cold for it to be a big factor, and even in Greenland it is only a summertime effect. "It's significant, but I don't think it's the primary mechanism that would be responsible for dramatic increases in sea level," says glaciologist Robert Bindschadler at the NASA Goddard Space Flight Center in Greenbelt, Maryland.
There is another way for surface melt to affect sea level, though. Meltwater fills any crevasses, widening and deepening the cracks until they reach all the way down to the base of the ice. This can have a dramatic effect on floating ice shelves. "Essentially, you are chopping up an ice shelf into a bunch of tall thin icebergs, like dominoes standing on their ends," says Bindschadler. "And they are not very stable standing that way." They fall over, and push their neighbours out to sea.
The most famous break-up in recent times - that of the Larsen B ice shelf on the Antarctic Peninsula in 2002 - likely happened this way. While the break-up of floating ice shelves does not raise sea level directly, the disintegration of Larsen B had consequences that models at the time failed to predict. With little to resist their advance, glaciers behind Larsen B immediately began to move up to eight times faster. Five smaller ice shelves in the rapidly warming Antarctic Peninsula have also broken up and many others are disintegrating.
What lies beneath
Surface melt poses little threat in West Antarctica, as it is so much colder. Here the danger comes from below. Take the ice shelf holding back the massive Pine Island glacier, which is thinning in a strange pattern. Radar scans have revealed giant "ripples" up to 100 metres deep on its underside.
Bindschadler thinks that the currents created by winter winds raise relatively warm water from a few hundred metres down in the Amundsen Sea off West Antarctica. This melts the underside of the ice shelf and gets trapped in the space it carves out, thus continuing to melt the ice from below over a few seasons. As the ice shelf thins, the Pine Island glacier behind it is speeding up, from 3 kilometres per year three years ago to over 4 kilometres per year according to the latest unpublished measurements by Ian Joughin of the University of Washington in Seattle.
What does this have to do with global warming? Climate change, aided and abetted by the loss of ozone, has strengthened the winds that circle Antarctica. This is speeding up the Antarctic circumpolar current and pushing surface waters away from the coast, causing deeper, warmer water to well up.
Along with the Thwaites glacier and some smaller ones, Pine Island glacier drains a third of the West Antarctic ice sheet. This ice sheet is particularly vulnerable to ocean heat because much of it rests on the seabed, a kilometre or more below sea level. This submarine ice will not raise sea level if it melts, but if it goes a lot of higher-level ice will end up in the ocean. The vulnerable parts contain enough ice to raise sea level 3.3 metres - less than the 5 metres that was once estimated but more than enough to have catastrophic effects.
Bindschadler has calculated that a change in ocean currents could potentially deliver up to 1019 joules of heat per year to the continental shelf off West Antarctica - and only about 109 joules per year would be required to melt the ice shelves that hold back the Pine Island and Thwaites glaciers. "The ocean has an enormous amount of heat compared to the atmosphere," he says.
Even in Greenland, where the ice sheet rests on land above sea level, ocean heat still matters. When not dodging giant icebergs, Holland has been trying to find out why Greenland's Jakobshavn glacier started moving faster in 1997, speeding up from around 6 kilometres per year to more than 9 kilometres per year by 2000 and 13 kilometres per year by 2003. The glacier continues to drain ice from the Greenland ice sheet at a higher rate than before.
The increase had been attributed to lubrication by meltwater, but Holland's team recently stumbled across data from local fishing boats, which deploy thermometers in bottom-trawling nets. One fact stood out: the temperature of the subsurface waters around West Greenland jumped in 1997, prior to the massive calving of Jakobshavn.
As the team reported last year, though, the real trigger lay in what happened in 1996. That year, the winds across the North Atlantic weakened, slowing down the warm Gulf Stream. The weakened current meandered aimlessly and hit west Greenland. "A modest change in wind gives you a big bang in terms of ice sheet dynamic response," says Holland.
Findings like these suggest that predicting sea level rise is even trickier than previously thought. If relatively small changes in winds and currents could have a big impact on ice sheets, we need extremely good models of regional climate as well as of ice sheets. At the moment we have neither - and while regional climate models are improving, ice sheet models are still too crude to make accurate predictions.
"They are coarse models that don't include mechanisms that allow glaciers to speed up," says Rignot. "And what we are seeing today is that this is not only a big missing piece, this could be the dominant piece. We can't really afford to wait 10 to 20 years to have good ice sheet models to tell people, 'Well, sea level is actually going to rise 2 metres and not 50 centimetres', because the consequences are very significant, and things will be pretty much locked in at that point."
So climate scientists are looking for other ways to predict sea level rise. Rahmstorf, for instance, is treating the Earth as one big black box. His starting point is the simple idea that the rate of sea level rise is proportional to the increase in temperature: the warmer Earth gets, the faster ice melts and the oceans expand. This held true for the last 120 years at least. "There is a very close and statistically highly significant correlation between the rate of sea level rise and the temperature increase above the pre-industrial background level," says Rahmstorf.
Extrapolating this to the future, based on IPCC emissions scenarios, suggests sea level will rise by between 0.5 and 1.4 metres - and the higher estimate is more likely because emissions have been rising faster than the IPCC's worst-case scenario. Rahmstorf's study got a mixed reception when it first appeared, but he can feel the winds of change. "I sense that now a majority of sea level experts would agree with me that the IPCC projections are much too low," he says.
Could even Rahmstorf's estimate be too low? It assumes the relation between temperature and sea level is linear, but some experts, most prominently James Hansen of NASA's Goddard Institute for Space Studies in New York, argue that because there are multiple positive feedbacks, such as the lubrication of glaciers by meltwater, higher temperatures will lead to accelerating ice loss. "Why do I think a sea level rise of metres would be a near certainty if greenhouse gas emissions keep increasing?" Hansen wrote in New Scientist (28 July 2007, p 30). "Because while the growth of great ice sheets takes millennia, the disintegration of ice sheets is a wet process that can proceed rapidly."
Hansen has made no specific prediction, however. So just how bad could it get? Tad Pfeffer of the University of Colorado in Boulder decided to work backwards from some of the worst-case scenarios: 2 metres by 2100 from Greenland, and 1.5 metres from West Antarctica, via the Pine Island and Thwaites glaciers. Just how fast would the glaciers have to be moving for the sea level to rise by these amounts? Pfeffer found that glaciers in Greenland would need to move at 70 kilometres per year, and Pine Island and Thwaites glaciers at 50 kilometres per year, from now until 2100. Since most glaciers are moving at just a few kilometres per year, to Pfeffer and many others, these numbers seem highly unrealistic.
So what is possible? For scenarios based on conservative assumptions, such as a doubling of glacier speeds, Pfeffer found sea level will rise by around 80 centimetres by 2100, including thermal expansion. "For the high end, we took all of the values we could change and we pushed them forward to the largest numbers we imagined would be reasonable," says Pfeffer. The answer: 2 metres.
These estimates fit well with recent studies of comparable periods in the past, which have found that sea level rise averaged up to 1.6 metres per century at times. There is a huge caveat in Pfeffer's number crunching, though. "An important assumption we made is that the rest of West Antarctica stays put. And this is the part of West Antarctica that is held behind the Ross ice shelf and the Ronne ice shelf," says Pfeffer. "Those two ice shelves are very big, and very thick, and very cold. We don't see a way to get rid of those in the next century."
Holland is not so sure. He has been studying computer models of ocean currents around Antarctica, and he doesn't like what he sees. The subsurface current of warm water near the frozen continent, known as the circumpolar deep water, branches near the coast, and one branch hits Pine Island - which is probably why the ice there is thinning and speeding up. "Another branch of it comes ever so close to the Ross ice shelf," says Holland. "In some computer simulations of the future, the warm branch actually goes and hits Ross."
While it is impossible to predict exactly what will cause this, the lessons from Jakobshavn show that a small change in the wind patterns over Antarctica might be enough to shift the warm current towards and eventually underneath the Ross ice shelf. Then even this gigantic mass of ice - about the size of France - becomes vulnerable, regardless of how cold the air above it is. Pfeffer agrees that the Ross and Ronne ice shelves are the wild cards. "If we pull the plug on those two, then we create a very different world."
Is there really a danger of a collapse, which would cause a sudden jump in sea levels? Paul Blanchon's team at the National Autonomous University of Mexico in Cancun has been studying 121,000-year-old coral reefs (pictured above) in the Yucatan Peninsula, formed during the last interglacial period when sea level peaked at around 6 metres higher than today. His findings suggest that at one point the sea rose 3 metres within 50 to 100 years.
We just don't know if this could happen again in the 21st century. What is clear, though, is that even the lowest, most conservative estimates are now higher than the IPCC's highest estimate. "Most of my community is comfortable expecting at least a metre by the end of this century," says Bindschadler.
Most glaciologists who study Greenland and Antarctica are expecting at least a metre rise by the end of the century
And it will not stop at a metre. "When we talk of sea level rising by 1 or 2 metres by 2100, remember that it is still going to be rising after 2100," Rignot warns.
All of which suggests we might want to start preparing. "People who are trying to downplay the significance say, 'Oh, the Earth has gone through changes much greater than this, you know, in the geological past'," says Pfeffer. "That's true, but it's completely irrelevant. We weren't there then."
What it all means
If a 1 metre rise in sea level doesn't sound like much, consider this: about 60 million people live within 1 metre of mean sea level, a number expected to grow to about 130 million by 2100.
Much of this population lives in the nine major river deltas in south and southeast Asia. Parts of countries such as Bangladesh, along with some island nations like the MaldivesMovie Camera, will simply be submerged.
According to a 2005 report, a 1-metre rise in sea level will affect 13 million people in five European countries and destroy property worth $600 billion, with the Netherlands the worst affected. In the UK, existing defences are insufficient to protect parts of the east and south coast, including the cities of Hull and Portsmouth.
Besides inundation, higher seas raise the risk of severe storm surges and dangerous flooding. The entire Atlantic seaboard of North America, including New York, Boston and Washington DC, and the Gulf coast will become more vulnerable to hurricanes. Today's 100-year storm floods might occur as often as every four years - in which case it will make more sense to abandon devastated regions and towns than to keep rebuilding them.
Anil Ananthaswamy is a contributing editor for New Scientist
By: Susie77, 1:40 AM GMT on July 01, 2009
Space Weather News for June 30, 2009
VOLCANIC SUNSETS: The Russian volcano that erupted directly beneath the International Space Station on June 12th is now causing beautiful lavender sunsets across parts of the northern USA and Europe. A plume of ash and sulfur dioxide from the Sarychev Peak eruption is circulating through the stratosphere, and when parts of the plume pass over an area at sunset, the sky fills with delicate white ripples, sometimes-colorful streamers, and a telltale hue of purple. Check today's edition for observing tips and a photo gallery.
The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.