Venus at bottom, Mercury at the top, Jupiter on the left, Earth in the foreground. Four of the 7 visible planets in one shot. We won’t see a closer grouping until 2026.
Neil Armstrong 1930 – 2012
I am sad to hear of the passing of astronaut Neil Armstrong.
There are many photos of Armstrong, but my favourite is this one take after the successful landing. Armstrong was a humble and private man, but the emotion displayed here is of someone who has just done the near-impossible.
At the time of the moon landings, Neil was age 38. When I think about what I was able to accomplish in my life when I was 38, and what those brave, brilliant explorers of space were able to accomplish, I gain a perspective on what humanity can really achieve.
I only wish I could see with my own eyes what those 24 Apollo astronauts saw.
Five Planets
This evening was a great night for astronomy, although it was damn cold. I could see Mercury, Venus, Mars, Earth and Jupiter, five of the eight planets in our solar system.
This past week was the first time I really saw the planet Mercury. I have likely seen it many times before without realizing it. Over the last few weeks, Mercury was at its greatest elongation from the sun, so I made sure that I took time to look for it.
To take the photos, I stayed in my car (motor off) and set my camera on the drivers side door. It was too cold to stand with a tripod while fiddling with the camera settings. I used manual mode.
I am so happy that I took time to do this.
Sunlight
Rosa woke up before me this morning and started her morning routine (doing her hair, picking out clothes).
Eventually I began to stir. She came back into the bedroom and opened the curtains, letting the sunlight flood in.
The sunlight was warm on my skin.
And I began to think about how incredible that was. The Sun is 150 million kilometres away. Only the most inconceivably small amount of photons that the Sun produces reached across that distance to alight upon my drowsy form.
Because I like numbers, here’s the deal. My arm is about 70 square centimetres, or 0.07 metres square. The total area of a sphere is That means that the area of the sphere of solar radiation at the distance of Earth’s orbit is 4 x π x 149,598,000 kilometres x 149,598,000 kilometres. That’s 2.8 x 10^17 square kilometres or 2.8 x 10^23 square metres. My arm was therefore receiving 0.000,000,000,000,000,000,000,024,89 percent (2.489 x 10^-23 %) of the photons that the Sun is producing, and even that infinitesimal amount was enough to warm my arm and wake me from my slumber.
Fukushima correction
More information has been coming out about the earliest moments of the Fukushima Dai-ichi nuclear incident and the design of the reactors. It turns out that I was incorrect in surmising that the results of the experiment at Chernobyl or perhaps continuing to run the reactors might have ameliorated some of the disaster.
Firstly, the Chernobyl experiment was only supposed to cover the 75 seconds from SCRAM to the point when the generators would have been supplying full power for cooling. Secondly, the 1986 disaster was actually the fourth time the experiment had been attempted – it had failed the previous three times. Which would lead one to conclude that it is not possible to bridge the loss of power by using residual steam pressure to continue to spin the turbines.
Next, the design of the Fukushima Dai-ichi reactors had flaws that would have defeated my suggestions. During the massive quake, the active reactors were SCRAMed. The diesel generators were brought online and were functional until the tsunami hit. The facility had 5.7 metre seawalls and the tsunami was estimated to be 13-15 metres high. This flooded many of the buildings. The older reactor buildings had their generators in the basement of the reactor building. The newer reactors at least provided external generators that were stationed up a hill. But all of the electrical switching components were still in the basement. As were the turbines. Even if steam had been available for the turbines, the turbines would still have been lost when the tsunami hit nearly an hour after the quake.
Finally, my suggestion would not have helped at Reactor 4, which was already shut down and could not supply any energy. The spent fuel pool next to the core contained 1,331 fuel rods. Alternative methods were used to cool the spent fuel in the pool.
Happy Anniversary Yuri & Columbia
Today is the 50th anniversary of the first man in space, Yuri Gagarin, and marks the 30th anniversary of the first flight of the Space Shuttle, STS-1.
It is remarkable that only 20 years separated the two events, and that so little has changed in the most recent 30 years. In that short initial span of time, space technology advanced at an incredible pace.
Yuri Garagin flew one orbit of the earth on April 12, 1961 (Vostok-1). So little was known about space at the time that the controls of his capsule were locked to prevent him from operating them – it was thought that zero-G would induce madness.
About three weeks later, Alan Shepard became the first American in space, although with a sub-orbital, 486 km flight (Mercury-Redstone 3 aka Freedom 7). Less than three weeks later, US President John F. Kennedy publicly set the goal to putting a man on the moon before the end of the decade. It was an incredible challenge. The US had less than 16 minutes of manned space flight experience at the time of the speech.
The American manned space programs moved at a breakneck pace. The Mercury program completed 2 years later. There was a 2-year gap before the first Gemini flights, which saw the first American two-man crews, the first American space walk, the first spacecraft rendezvous and docking, and much longer flights (Gemini VII was 13 days, 18 hours). The Gemini program wrapped up at the end of 1966, making way for the Apollo program.
The first manned Apollo flight, Apollo 7, was 2 years after the end of the Gemini program. Part of the reason for the gap was the deadly cabin fire on Apollo 1 in January 1967, which was being tested for a possible first flight in February. The fire and investigation, combined with program challenges for the Apollo CSM and LM landers, led to the delay. Boldly, the Apollo 8 mission actually reached moon orbit – a daring objective for only the second manned flight of the program.
With the goal of a manned landing on and returning from the moon accomplished on July 16, 1969, winning the moon-landing race against the Soviets, the funding for Apollo was drawn down. It was only 8 years and 3 months from Gagarin’s flight to the touchdown of Apollo 11 in the Sea of Tranquility on the moon.
The final flight to the moon was Apollo 17 at the end of 1972. Some of the Apollo equipment was used for the Skylab space station, manned for 171 days in 1973 and 1974, followed by the mid-decade Apollo-Soyuz flight. From that point, there were no manned American space flights until STS-1 on April 12, 1981.
The early designs of the Space Shuttle systems date back even before the moon landing. President Nixon approved the program in 1971. It took 10 years to build and test the first two Shuttles – Enterprise, which was only used for approach and landing tests from a converted Boeing 747, and Columbia which was a fully functional orbiter. It looks less time to move from the first manned suborbital space flight to landing on the moon.
Since the start of the Shuttle era, I feel the US manned space program has stagnated. For 30 years, the US has entirely depended on the shuttle for all manned flights. Again, that’s three times longer than it took to go from Yuri’s flight to landing on the moon. I feel that the US should have been spending more on trying out new technologies.
While I am fully supportive of the International Space Station, and feel that it should be the springboard for any future above-low-orbit manned missions, it hasn’t really pushed forward the manned program. It has provided a workspace for research of course, but it’s not about manned flight really. It’s about a zero-G research facility. It’s also not the first space station – it’s been done before.
Without producing any new vehicles for the past 30 years, it would be like the aviation industry stopping creating new planes with the Boeing 707, or if computer science stopped once IBM created the System/360.
In the future, I would like to see the US exploring new ways and new vehicles for its manned program. Allowing private space companies to provide services is an interesting direction but I am concerned that NASA would be without any space program, should these private companies (who are doing it for a profit) either fail or decide that it is not financially viable for them to continue. Then what will NASA do? It seems directionless at the moment.
I have some strong opinions and I’m working on an essay about the future of NASA.
News Overload
I feel like I’m suffering from news overload. There is so much going on. Who would have predicted any of the events of the first 11 weeks of 2011 (also, the first 11 weeks of the new decade). What’s going to happen in the next 41 weeks?
First, the UN declares a no-fly zone over Libya. With the opposition forces pushed back from the outskirts of Tripoli to their main area of control in Benghazi, it almost seems too late. They had almost completed the overthrow of their dictator ruler and soon lost momentum within sight of their goal.
Then CBC reported that special forces have already been in Libya. I didn’t know that. What the hell are special forces doing in a foreign country like that? That doesn’t seem right, even if Qaddafi is a complete nut case. I’m so conflicted – the people of Libya deserve freedom, but I would hesitate to engage another country militarily, especially after the stellar jobs the Western powers have done in Iraq, Pakistan, Lebanon, Cambodia, Iran, Yemen and Somalia, just to name a few.
And just minutes ago, CNN announced that Libya is calling for a cease-fire, which would be a good sign if true.
In Japan, the International Atomic Energy Agency (IAEA) has announced that the problems at Fukushima are now a Level 5 nuclear incident on the International Nuclear and Radiological Event Scale. This is equal to the Three Mile Island incident.
In Yemen, 45 people were massacred while protesting against the government.
And for some good news, you have to leave the planet. For the first time in history, a space probe has entered the orbit of Mercury. Surprisingly, probes have already been in orbit around Venus, the Earth and Moon, Mars, Jupiter and Saturn, but not Mercury. The surface of Mercury was only 40-45% mapped before the MESSENGER probe was launched. We know far more about Saturn, which is 14 times further away (0.6 AU vs 8.5 AU).
The continuing efforts at Fukushima
As with everyone outside of the Middle East (where people are dealing with the continuation of the Libyan civil war and the invasion of Bahrain by foreign troops), I’ve been watching the events at the Fukushima I nuclear power plant.
Firstly, the on-going heroic effort to contain or reduce the damage at the plant is incredible. Unlike Chernobyl, where the disaster was complete in just seconds (a massive explosion) and the rest of the effort was to contain the damage already inflicted, the cascading disaster at Fukushima is about trying to stop further damage. In my mind, it is more like Apollo 13, where one issue was resolved just in time for a new issue to arise. At Fukushima, the loss of power, then the loss of backup power led to overheating, which required steam releases, which caused hydrogen explosions, which damaged the other cooling apparatus for other parts of the plant, which was impacted by an oil fire, and so forth. The three reactors that were operating at the time of the earthquake are possibly damaged, but to what extent no one seems to know for certain. Now the cooling pools that I mentioned yesterday are overheating. In one report, the pool has boiled dry, a very bad situation.
There is so much conflicting information about what is really happening there. In that respect, I have to say it is eerily similar to the lack of good information during the early days of the Chernobyl disaster. Timely information about Chernobyl was not freely available as that event happened near the end of the cold war and the communist control of the country did not allow a free press.
Secondly, I am surprised at how many people have offered their own definitive opinion on the issue, which is often formed without little hard data.
MIT professor Dr Josef Oehmen posted a blog message entitled “Why I am not worried about Japan’s nuclear reactors” (which has since been modified). He made the claim that “there was and will *not* be any significant release of radioactivity from the damaged Japanese reactors.” It was a stunning act of hubris considering the lack of reliable, available information. It turns out that he is not a nuclear specialist, but rather a risk management specialist. In my opinion, no one can predict what new fault will occur. Predicting that nothing more will happen when there is not enough information at present seems like a poor risk assessment technique to me.
Others in the US and Europe have also chimed in on their opinions. France’s ASN nuclear safety authority said that the incident should be classified as Level 6 on the International Nuclear Event Scale (INES). Some have speculated that the situation is both worse and better than is being reported. It seems few are being honest that they do not have enough information.
Lewis Page at The Register posted today that “Still No Cause for Alarm” where he claimed that “there remain no grounds for anyone to fear for their health.” The New Scientist published, “Why Fukushima Daiichi won’t be another Chernobyl” while Scientific American published “Fukushima Will Be [a] Wasteland” which has the statement “This is going to be like Chernobyl.”
On CBC Radio this morning, during the 9:00am hourly news, the newsreader claimed that 5 workers at Fukushima had died, at least one of them from radiation. I believe that was a mistake by CBC or the reader.
In Japan, reports over the past few days indicate that radiation levels are up to 400 or 800 times higher than the legal limit, depending on the day and source of the report. Helicopters were being used to dump water on the plant, but had to stop because the radiation levels were too high. Some airline passengers arriving from Japan have been found with low levels of radiation.
According to Salon.com: U.S. Nuclear Regulatory Commission Chairman Gregory Jaczko is saying the cooling pool is completely dry, without giving any details on how he came to this conclusion. Tokyo Electric Power, which owns and runs the plant, is saying it is not empty. The difference in opinions is itself newsworthy.
There is unexplained white smoke coming from one of the reactor buildings. There was an explained “loud noise” at the plant. How can anyone truly feel they can predict that everything will be fine (Dr Oehman, Lewis Page) if all the current facts are not even available?
I just don’t understand how there can be so many opinions when there are just not enough facts.
Fukushima I Nuclear Power Plant – continued
I continue to follow the events at the nuclear power plants hit by the 2011 Sendai earthquake and tsunami.
I had one of those d’oh moments. Whereas yesterday I was confused by the continuing issue with cooling a subcritical reactor, today I realized I should have known this all along. D’oh.
The heat currently being generated in the subcritical reactors is from decay heat. It’s not from the primary nuclear reaction that is used to generate heat and power. But rather it is because of the products of the nuclear power generation.
The fission of the uranium (and in some cases plutonium) is the process of the large unstable atomic nucleus splitting into two lighter nuclei and releasing neutrons (which then can continue the reaction by causing other uranium nuclei to split) and energy (following the famous E=mc^2 mass-energy equivalence equation).
The smaller nuclei produced by fission are often also radioactive. Meaning they also decay by fission over time. The description of how frequently the smaller fission products themselves decay is measured by the half-life of the isotope. The description of the chain of radioactive decays is called the decay chain. For nuclear fuel, this decay chain ends with the stable lead nucleus.
The heat being generated in the subcritical core is simply the natural process of the fission products decaying down to a stable nuclei. This natural fission also produces heat. Over time, the heat produced will decrease, at a rate defined by the half-lives of all of the products and sub-products.
The d’oh moment was when I realized that that is why the used fuel rods are always kept in a cooling pool next to the reactor. Otherwise, if there was not ongoing heat from the spent fuel, the used fuel rods could just be left in a secure warehouse. I knew about the cooling pools, but never connected it to the heat from the decay chain.
Fukushima I Nuclear Power Plant
After the “Arab Spring” events in Middle East and northern Africa, comes the devastating quake in Japan. I’ve been glued to the major news websites for weeks.
The horrific Sendai quake and tsunami in Japan is stunning. There is so much video available of the event – certainly one of the most recorded natural disaster I can remember.
Today, the focus is on the Fukushima I Nuclear Power Plant, a complex with six BWR (boiling water reactor) reactors. Just minutes ago, BBC was reporting that the cooling for reactor #3 has completely failed.
I’ve been very confused by what’s happening at the plant over the last 36 hours. The confusion is because I did not understand some of the nuances in reactor design.
I knew from previous reports and from general knowledge that the reactors would have been SCRAMed immediately during the earthquake. That would lower the control rods into the reactor core, thus stopping the chain reaction. The rods control the amount of neutrons that are moving around the core. The rods are there to prevent the self-sustaining nuclear chain reaction, and thus lower the amount of power and heat generated.
So the problems at the plant were confusing. If the rods had been lowered, why was cooling still a problem?
Searching the web and wikipedia, I discovered that even if the reactor is shutdown (“subcritical”), there is still residual heat in the core that must be cooled. This is the cause of the problems in Fukushima. Although the chain reaction has stopped, there is still some spontaneous fission occurring, plus the heat that was in the core at the time of the SCRAM.
Something else bothers me about the first day of the crisis. On Friday, Secretary of State Hillary Clinton stated that “We just had our Air Force assets in Japan transport some really important coolant to one of the nuclear reactors.” She used the past-tense instead of future tense, meaning that it had already been done. The Reuters report about her statement was posted only 10h 19m after the quake; the White House web page does not have a timestamp. A video of her remarks is here: http://www.state.gov/video/?videoid=822710919001.
So far, I have not seen anyone in the press ask further questions about this. I have lots of questions.
1. What coolant was sent? Japan uses light water, which is basically normal water. It is different from heavy water used in other reactors; heavy water is where all of the hydrogen in the water molecules have an extra neutron to form deuterium. Is that what was sent?
2. Where did this coolant come from? Was it just sitting around on hand? Next to an air base?
3. How was it transported? In thousands of Evian bottles? What sort of container or containers? How much was delivered to the nuclear plant(s)?
4. How did the Air Force deliver the coolant? Was it a plane or a helicopter? The Secretary specifically said “so Air Force planes were able to deliver that”. If it was delivered by plane, then where did the planes land? Are there airstrips next to the nuclear plants? If the plants were hit by the tsunami, then any airstrip nearby would have also been hit and most likely useable. It is possible that it was a CV-22B Osprey, which can land vertically, but the Air Force only has 12 of them, none of them in Japan as far as I can tell. The Air Force also has two types of helicopters in inventory – the UH-1N Huey/Iroquois and the HH-60 Pave Hawk search and rescue helicopters. The HH-60 can sling about 8,000 pounds, and the UH-1 can sling about 5,000 pounds. That doesn’t seem like a lot of coolant capacity per helicopter, if that was actually the delivery mechanism. Another possibility is that Clinton said Air Force, but meant Marines, as they do have more inventory of helicopters and Osprey. I suppose to a politician, all planes are Air Force planes.
As I said, what Clinton said just seemed odd, although I cannot specifically tell what are the actual facts. Strangely, the Air Force web site makes no mention of this activity all. I would think that if they were involved in an important mission like trying to save a reactor, it would be all over the Air Force news web page.