Monday, August 29, 2011
Recent statistics on Marriage
According to the PBS news, based on 2010 U.S. census bureau, 30% of Americans have never been married, the largest percentage ever recorded. More people in their thirties and forties are single and never married, not divorced or widowed. Also, people in southern and western regions have the highest rate of divorces in the U.S. The southern region surprised me.
Friday, August 26, 2011
The hottest and driest summer
According to NPR radio this morning, this summer has been the hottest and driest summer on record in the United States, and the drought has cost the agriculture industry more than 5 billion dollars and counting.
Related:
http://www.npr.org/2011/08/26/139947317/drought-puts-texas-ranchers-and-cattle-at-risk
http://www.ktul.com/story/15176316/2011-on-pace-for-hottest-driest-summer-on-record
Related:
http://www.npr.org/2011/08/26/139947317/drought-puts-texas-ranchers-and-cattle-at-risk
http://www.ktul.com/story/15176316/2011-on-pace-for-hottest-driest-summer-on-record
Thursday, August 25, 2011
Hurricane 101
After being surprised with the largest earthquake in our region this past week, now we have time to prepare for the next natural disaster: Hurricane Irene. What should you do and have before, during, and after a major Hurricane.
I know I have to do grocery shopping, have flash lights, battery powered radios, enough water and food to last you days, but is that it?
Here is Red Cross's Checklist for Hurricane readiness:
http://www.redcross.org/www-files/Documents/pdf/Preparedness/checklists/Hurricane.pdf
Stay safe!
I know I have to do grocery shopping, have flash lights, battery powered radios, enough water and food to last you days, but is that it?
Here is Red Cross's Checklist for Hurricane readiness:
http://www.redcross.org/www-files/Documents/pdf/Preparedness/checklists/Hurricane.pdf
Stay safe!
Wednesday, August 24, 2011
WISE Eyes: Coolest Stars
Not long after detecting the darkest planet ever by the Kepler mission, now we have the news of seeing the coldest class of stars via WISE eyes!
How cold are they? As cold as our bodies or cooler. You think that is not cold enough? It is very cold for a star, just compare it with our own Sun! Well, technically they belong to a star-like class of celestial bodies called brown dwarfs, believed to be failed stars. They just did not make it even though they were well on their way of becoming a star.
Reference:
http://www.nasa.gov/mission_pages/WISE/news/wise20110823.html
How cold are they? As cold as our bodies or cooler. You think that is not cold enough? It is very cold for a star, just compare it with our own Sun! Well, technically they belong to a star-like class of celestial bodies called brown dwarfs, believed to be failed stars. They just did not make it even though they were well on their way of becoming a star.
Reference:
http://www.nasa.gov/mission_pages/WISE/news/wise20110823.html
Tuesday, August 23, 2011
Earthquake 101
Today Washington D.C. area experienced the largest earthquake (5.8 magnitude) known to ever hit this region!* Apparently we east coast people are not well-educated about what to do or not to do during an earth quake. Everyone evacuated their buildings. Now we know earthquake protocol is to find a safe place inside the building: (e.g. under the table/desk, etc). I knew this but at the moment when it happened, I reacted like I would to fire alarms and other emergencies: evacuate! Maybe because we are so used to other threats and hazards in this region requiring us to evacuate once in a while. I was not alone, everyone came out, and everyone was wrong. However, to our credit, the quake did trigger our fire alarms. So, we were responding to that as well! Besides, we did not have much choice. We were not allowed inside the building and were told to stay out! In fact we were sent home so that all buildings be inspected and cleared by structural engineers!. Here is Red Cross' Check List of what to do or not to do during an earthquake.
Next, in any emergency, if everyone calls each other, as you might have realized today, the lines get congested and cannot handle the communications traffic when it is needed the most. So try just texting or not using the lines as much as possible so that emergency response personnel and those more in need be able to use the lines.
Finally, on a personal note, it is good to have cash, extra car, home keys in different places. We were not allowed to get back to our offices until all buildings were cleared and inspected. I had my keys and cell phone but my purse with my credit cards and money are all inside the office!
* http://www.foxnews.com/scitech/2011/08/23/washington-area-has-history-earthquakes/
p.s. Many west-coasters or those on other major earthquake lines may think we are making a huge deal out of nothing since they constantly deal with such earthquakes. However, please keep two points in mind: 1) our building codes are not designed for enduring earthquakes and yours are. 2) The earth crust in those regions is fragmented so earthquakes are felt locally, whereas here the earth crust is all one huge connected piece and that is why the waves traveled to many states including NY, NC, and even Toronto, CA.
Next, in any emergency, if everyone calls each other, as you might have realized today, the lines get congested and cannot handle the communications traffic when it is needed the most. So try just texting or not using the lines as much as possible so that emergency response personnel and those more in need be able to use the lines.
Finally, on a personal note, it is good to have cash, extra car, home keys in different places. We were not allowed to get back to our offices until all buildings were cleared and inspected. I had my keys and cell phone but my purse with my credit cards and money are all inside the office!
* http://www.foxnews.com/scitech/2011/08/23/washington-area-has-history-earthquakes/
p.s. Many west-coasters or those on other major earthquake lines may think we are making a huge deal out of nothing since they constantly deal with such earthquakes. However, please keep two points in mind: 1) our building codes are not designed for enduring earthquakes and yours are. 2) The earth crust in those regions is fragmented so earthquakes are felt locally, whereas here the earth crust is all one huge connected piece and that is why the waves traveled to many states including NY, NC, and even Toronto, CA.
Monday, August 22, 2011
Space Weather
It was only 51 years ago, on April 1, 1960, that NASA's first weather satellite, TIROS-1, was launched. Back then, weather satellite technologies, weather forecasting models, ...were at their infancy. I would imagine scientists having a hard time convincing politicians about the importance of weather satellites, get budget for it, etc. Now, so many industries such as agriculture, tourism, aviation, and navigation all rely on these satellites' data, weather models and forecasts for their day-to-day business. We take the convoluted process of designing, building, testing, launching, and operating weather satellites, processing their data, and improving existing models all for granted.
Now, space weather is as new to us as weather forecasting business was 50 years ago. Understanding atmospheres and weathers of the celestial bodies in our solar system and their effects on the Earth's atmosphere and our satellites and spacecrafts there are as vital and necessary for us as weather modeling and satellites are. For example, solar flares and eruptions can disrupt our communication and navigation satellites*. Imagine a day when your cell phones and GPS devices do not work, and nor does the communications and navigation of the airline and navigation industry. That is a doomsday scenario, one that Solar Dynamics Observatory and Stereo are trying to understand better and help us prepare for.
Today the news of a major milestone was announced:
For the first time we have been able to track a space storm!**
You can learn more about space weather and look at current space weather and forecasts via
http://www.swpc.noaa.gov/SWN/ , or
http://helios.gsfc.nasa.gov/weather.html.
You can also install Space Weather Apps developed by NASA on your smart phone, even though they may not work during an bad space storm!
* http://hesperia.gsfc.nasa.gov/sftheory/spaceweather.htm
** http://www.nasa.gov/mission_pages/stereo/news/solarstorm-tracking.html
Now, space weather is as new to us as weather forecasting business was 50 years ago. Understanding atmospheres and weathers of the celestial bodies in our solar system and their effects on the Earth's atmosphere and our satellites and spacecrafts there are as vital and necessary for us as weather modeling and satellites are. For example, solar flares and eruptions can disrupt our communication and navigation satellites*. Imagine a day when your cell phones and GPS devices do not work, and nor does the communications and navigation of the airline and navigation industry. That is a doomsday scenario, one that Solar Dynamics Observatory and Stereo are trying to understand better and help us prepare for.
Today the news of a major milestone was announced:
For the first time we have been able to track a space storm!**
You can learn more about space weather and look at current space weather and forecasts via
http://www.swpc.noaa.gov/SWN/ , or
http://helios.gsfc.nasa.gov/weather.html.
You can also install Space Weather Apps developed by NASA on your smart phone, even though they may not work during an bad space storm!
* http://hesperia.gsfc.nasa.gov/sftheory/spaceweather.htm
** http://www.nasa.gov/mission_pages/stereo/news/solarstorm-tracking.html
Friday, August 19, 2011
گعده
امروز اين كلمه رو در پست يكى از دوستان در فيسبوك ديدم. به روايت ويكى پيديا، گعده در عربى قعده است و به معناى دور هم نشستن و شب نشينى و خوش و بش كردن هست. من نميدانم چرا با وجوديكه من عاشق اين كارم و اين همه هم ما ايرانى ها اين كار را ميكنيم تا به حال اين كلمه را نشنيده بودم؟ آيا اين كلمه خيلى رايج و جا افتاده است؟
Reference:
http://fa.wikipedia.org/wiki/%DA%AF%D8%B9%D8%AF%D9%87
Reference:
http://fa.wikipedia.org/wiki/%DA%AF%D8%B9%D8%AF%D9%87
Thursday, August 18, 2011
The Darkest Planet
NASA's Kepler spacecraft, designed to find Earth-size planets and smaller around a star has been doing a magnificent job so far. In the first data release, the Kepler team identified 1235 candidate planets around 997 stars. A second data release is scheduled for September 2011 [1]. "The team estimated that 5.4% of stars host Earth-size planet candidates and 17% of all stars have multiple planets" [2]. Most importantly, from those candidates, scientists announced the discovery of the darkest world and planet ever. One that reflects only less than 1% of the light that it receives. It is a giant gas planet, orbiting too close to its sun star, 750 light years away from us [3]. Detecting such far and dark planet by Kepler is amazing! The transit method is working like clock-work by the book.
[1] http://www.nasa.gov/mission_pages/kepler/main/index.html
[2] http://en.wikipedia.org/wiki/Kepler_%28spacecraft%29
[3] http://www.npr.org/blogs/13.7/2011/08/18/139745242/the-darkest-world-scientists-discover-darth-vader-planet?sc=fb&cc=fp
[1] http://www.nasa.gov/mission_pages/kepler/main/index.html
[2] http://en.wikipedia.org/wiki/Kepler_%28spacecraft%29
[3] http://www.npr.org/blogs/13.7/2011/08/18/139745242/the-darkest-world-scientists-discover-darth-vader-planet?sc=fb&cc=fp
Wednesday, August 17, 2011
Assateague Island National Seashore
My friends and I also visited the Assateague Island National Seashore in Maryland. It is one of the few places in the United State where you can see wild horses. We saw many of them. They were beautiful.
Interactions of wind, ocean waves, and the Island make life on this coast very dynamic and hard to adapt to, as the plants and animals on this shape-changing and dynamic Island can do. Here is the list of animals and wild life on this Island, including the horseshoe crab.
"
[1] http://www.nps.gov/asis/naturescience/index.htm
[2] http://www.nps.gov/asis/naturescience/animals.htm
Interactions of wind, ocean waves, and the Island make life on this coast very dynamic and hard to adapt to, as the plants and animals on this shape-changing and dynamic Island can do. Here is the list of animals and wild life on this Island, including the horseshoe crab.
"
Did You Know? ...that horseshoe crabs may save your life? A protein in their blood is used to test injectable drugs for bacterial contamination. " [2] |
[1] http://www.nps.gov/asis/naturescience/index.htm
[2] http://www.nps.gov/asis/naturescience/animals.htm
Tuesday, August 16, 2011
Fat for Freedom!
If you did not know by now, we have everything in Maryland! We even have a Berlin, a lovely little city with a historic downtown. My friends and I stopped there one noon and found it appropriate to have a Hamburger in a place called Rayne's Reef*. The place was nice and made me nostalgic of Hamburger places back home.
There was another reason the place seemed familiar! Oh, wow, they had filmed the "Runaway Bride" there. How lovely to eat where Julia Roberts and Richard Gere were making a film and sharing a meal. Well, I am diverging from the real lesson of that day. The restaurant was full of images and reminders of the World War II. There was a sign encouraging people or maybe the workers and the Chef not to throw away extra and unwanted fats. Why? They were used for making gunpowder! Did you know that? Apparently, housewives were encouraged to save fat for freedom!
* http://www.raynesreef.com/
There was another reason the place seemed familiar! Oh, wow, they had filmed the "Runaway Bride" there. How lovely to eat where Julia Roberts and Richard Gere were making a film and sharing a meal. Well, I am diverging from the real lesson of that day. The restaurant was full of images and reminders of the World War II. There was a sign encouraging people or maybe the workers and the Chef not to throw away extra and unwanted fats. Why? They were used for making gunpowder! Did you know that? Apparently, housewives were encouraged to save fat for freedom!
* http://www.raynesreef.com/
Saturday, August 13, 2011
Reef
Okay, I should have probably named this blog "one lesson a (working) day"! I often times find it hard to update this blog during weekends and during my vacation, like this past week. I know, that is no excuse and I am making up for the lost time and backdating the posts for make-up-lessons.
So, I am in Ocean City, Maryland. Tonight is my last night here, and as I am typing these I am enjoying the sound of the Atlantic ocean's waves. It will be appropriate to use lessons learned in this trip. So many stores and things in this town were called "reef" this and "reef" that. What does reef mean anyways?
Here is the meaning of reef.
So, I am in Ocean City, Maryland. Tonight is my last night here, and as I am typing these I am enjoying the sound of the Atlantic ocean's waves. It will be appropriate to use lessons learned in this trip. So many stores and things in this town were called "reef" this and "reef" that. What does reef mean anyways?
Here is the meaning of reef.
Friday, August 12, 2011
Mad and Depressed?
No worries, apparently that is what world needs more of! According to Dr. Nassir Ghaemi, the author of "A First Rate Madness", manic people are more creative and depressed people have more empathy and are more realistic! Now, I wonder if it was because they were too creative and too empathetic that they got madly depressed to begin with? Is it a one way cause-effect or a two-way relationship? I guess I have to read his book. His ideas actually makes sense to me, well just the little that I heard here:
http://www.colbertnation.com/full-episodes/mon-august-8-2011-nassir-ghaemi
http://www.colbertnation.com/full-episodes/mon-august-8-2011-nassir-ghaemi
Tuesday, August 9, 2011
"Gratitude never radicalized anybody"
"Our job is not to make young women grateful. It is to make them ungrateful so they keep going. Gratitude never radicalized anybody"
"There shall never be another season of silence until women have the same rights men have on this green earth."
"I think the girl who is able to earn her own living and pay her own way should be as happy as anybody on earth. The sense of independence and security is very sweet."
"Cautious, careful people, always casting about to preserve their reputation and social standing, never can bring about a reform. Those who are really in earnest must be willing to be anything or nothing in the world's estimation, and publicly and privately, in season and out, avow their sympathy with despised and persecuted ideas and their advocates, and bear the consequences..."
"Woman must not depend upon the protection of man, but must be taught to protect herself.
Susan B. Anthony: Learn about her and her life if you get a chance!
"There shall never be another season of silence until women have the same rights men have on this green earth."
"I think the girl who is able to earn her own living and pay her own way should be as happy as anybody on earth. The sense of independence and security is very sweet."
"Cautious, careful people, always casting about to preserve their reputation and social standing, never can bring about a reform. Those who are really in earnest must be willing to be anything or nothing in the world's estimation, and publicly and privately, in season and out, avow their sympathy with despised and persecuted ideas and their advocates, and bear the consequences..."
"Woman must not depend upon the protection of man, but must be taught to protect herself.
Susan B. Anthony: Learn about her and her life if you get a chance!
Monday, August 8, 2011
What does it take for them to compromise?
These days the economic crisis of the U.S. is the headline of all news and breaking news. Each party blames the other for not compromising, for putting their interests before the interests of the nation and the good of the country, etc. They take their own government's employees hostage to cut deals with each other. Letting millions of families and employees live in limbo, leaving work on a Friday afternoon not knowing if they will be at work on Monday. Both parties, like mad old married couples, bring out irrelevant issues at such times. When there was a threat of a shutdown over finalizing fiscal year 2011 budget half way through fiscal year 2011, they made the disagreement be about government funds given to a clinic for women's health, and oh, God, guess what they do, they perform abortion procedures! It did not help repeating a zillion times that federal law prohibits them to use federal funds for abortion. It was like yelling to deaf ears. It did not matter. They wanted the public to hear and beleive what they wanted them to hear and believe. It did not matter that the money they were talking about was maybe 0.005% of the federal civilian budget and that the federal civilian budget is a small fraction of the military budget! It did not matter! They had to hold any grudge they could at the price of millions of govenrment employees. So much honor and respect was floating around for public service.
FAA employees had been through this shutdown threat twice this year already. The first time with everyone else over FY11 budget and the second time as their agency was singled out and they indeed did experience a shutdown this time. The fights seemed to be over financial issues but it became over unions and having union rights, etc.
The U.S. was fast approaching its debt ceiling and parties did not work out a deal fast enough to increase it or straighten out plans for mitigating long term debt affects. The whole circus was so painful and frustrating to watch, that I did not follow the details. I just know the signed off on something but it was not fast enough, and America lost its good credit score.
FAA employees were at home throughout this whole ordeal, and they prbably thought, the debt ceiling thing was of a higher priority than them, the airline safety, etc. The poor FAA administrator on TV was begging: this is summer time, the construction time, and they have stopped our work and contracts. We are losing construction time, revenue, jobs, taxes. Congress's response: it is time for our 5 week summer recess!
Who in government takes 5 weeks of recess that these guys should in such crisis. No sense of urgency, no sense of guilt, no sense of shame, no sense of empathy, nothing! I do not understand how it is that we stay weekends and nights, postpone our summer vacations till say our summer interns are gone, project deadlines met, ... , but they can let the country lose 1 trillion dollars in airfare taxes, lose construction jobs and employees' taxes, risk safety of the passengers in the air, and go on a five week vacation. Similarly, I do not know what it takes for airlines and FAA workers who continued working without pay to go on strike. For all airlines to show solidarity and empathy and not fly until issues are resolved; or maybe no airline or pilot flies any congress man/woman to their vacation destination. Pilots have the authority of not flying if they do not want someone on the plane! What does it take for anyone to do something?
I tell you. This issue was getting some good media attention and publicity. They were on their case day and night. Before you knew it, Friday they came and signed a budget and Monday FAA employees were back to work. All it takes is to take their vacation hostage: you cannot go till you sign a deal, or we make you pay for it for the rest of your life. Oh, and did we mention elections are on the corner?
Lesson I learned: media has great power and that all it takes for politicians to compromise and forget their disagreements is to stand between them and their vacation. Their patriotism, humanity, sense of duty, conscious, or whatever you like to call it does not work, at least not in a capitalist country. Their vacation does! Now, can you imagine what would happen if we stand between them and their salaries? You won't get paid until you do your job, which is to have a fiscal budget ready before the year starts!
FAA employees had been through this shutdown threat twice this year already. The first time with everyone else over FY11 budget and the second time as their agency was singled out and they indeed did experience a shutdown this time. The fights seemed to be over financial issues but it became over unions and having union rights, etc.
The U.S. was fast approaching its debt ceiling and parties did not work out a deal fast enough to increase it or straighten out plans for mitigating long term debt affects. The whole circus was so painful and frustrating to watch, that I did not follow the details. I just know the signed off on something but it was not fast enough, and America lost its good credit score.
FAA employees were at home throughout this whole ordeal, and they prbably thought, the debt ceiling thing was of a higher priority than them, the airline safety, etc. The poor FAA administrator on TV was begging: this is summer time, the construction time, and they have stopped our work and contracts. We are losing construction time, revenue, jobs, taxes. Congress's response: it is time for our 5 week summer recess!
Who in government takes 5 weeks of recess that these guys should in such crisis. No sense of urgency, no sense of guilt, no sense of shame, no sense of empathy, nothing! I do not understand how it is that we stay weekends and nights, postpone our summer vacations till say our summer interns are gone, project deadlines met, ... , but they can let the country lose 1 trillion dollars in airfare taxes, lose construction jobs and employees' taxes, risk safety of the passengers in the air, and go on a five week vacation. Similarly, I do not know what it takes for airlines and FAA workers who continued working without pay to go on strike. For all airlines to show solidarity and empathy and not fly until issues are resolved; or maybe no airline or pilot flies any congress man/woman to their vacation destination. Pilots have the authority of not flying if they do not want someone on the plane! What does it take for anyone to do something?
I tell you. This issue was getting some good media attention and publicity. They were on their case day and night. Before you knew it, Friday they came and signed a budget and Monday FAA employees were back to work. All it takes is to take their vacation hostage: you cannot go till you sign a deal, or we make you pay for it for the rest of your life. Oh, and did we mention elections are on the corner?
Lesson I learned: media has great power and that all it takes for politicians to compromise and forget their disagreements is to stand between them and their vacation. Their patriotism, humanity, sense of duty, conscious, or whatever you like to call it does not work, at least not in a capitalist country. Their vacation does! Now, can you imagine what would happen if we stand between them and their salaries? You won't get paid until you do your job, which is to have a fiscal budget ready before the year starts!
Thursday, August 4, 2011
Just static?
Do you remember the static on analogue TVs? If you live in the U.S. the analogue signals are not broadcast anymore, and what it means is that our old friend, the TV static, is gone. Well, why should we care you ask? Just for childhood memories? What were you calling those when you were a kid? Did you compare them with snow flakes like most kids do? Well, I for one have a good memory of my brother pulling my leg about it once.
One day after school he ran to my room, excited and happy. "Have you heard about the new cartoon?", he asked. "No, what cartoon?". Now, let's get some perspective,as it is always good. At that time we were living in Iran. It was during war years. We had only two public channels, each having programs for children one hour a day only. Not all their cartoons were brand new either. Some we had watched several times. Anyways, he told me how it was a foreign made brand new cartoon, maybe European or American. It was fictional too! It was about colony of aunts trying to survive a hard winter. It always snowed where they lived, and yet ants, the hardworking organized creatures they are, they always survived. It was about their stories and struggles, and if it was not exciting enough, that show was on all the time whenever there was no other program. That was like a dream show! You can imagine my face when we turned on the TV after running downstairs impatiently for me to see this brand new cartoon. That was my most exciting experience with TV static.
Now, I have learned it was something even more exciting! Not just because of our imagination and story telling talents in absence of enough entertainment, but for our own amazing universe and how it was born. Did you know that every time you watch static on TV, you are also observing parts of the Big Bang? The microwave radiations it had sent us billions of years ago, which have just reached us? Is not that amazing? Do not you miss watching Big Bang on your own TV?
http://www.youtube.com/watch?v=DjLtdorH0iE
The child in me is happy to get back at my brother with a better story.
One day after school he ran to my room, excited and happy. "Have you heard about the new cartoon?", he asked. "No, what cartoon?". Now, let's get some perspective,as it is always good. At that time we were living in Iran. It was during war years. We had only two public channels, each having programs for children one hour a day only. Not all their cartoons were brand new either. Some we had watched several times. Anyways, he told me how it was a foreign made brand new cartoon, maybe European or American. It was fictional too! It was about colony of aunts trying to survive a hard winter. It always snowed where they lived, and yet ants, the hardworking organized creatures they are, they always survived. It was about their stories and struggles, and if it was not exciting enough, that show was on all the time whenever there was no other program. That was like a dream show! You can imagine my face when we turned on the TV after running downstairs impatiently for me to see this brand new cartoon. That was my most exciting experience with TV static.
Now, I have learned it was something even more exciting! Not just because of our imagination and story telling talents in absence of enough entertainment, but for our own amazing universe and how it was born. Did you know that every time you watch static on TV, you are also observing parts of the Big Bang? The microwave radiations it had sent us billions of years ago, which have just reached us? Is not that amazing? Do not you miss watching Big Bang on your own TV?
http://www.youtube.com/watch?v=DjLtdorH0iE
The child in me is happy to get back at my brother with a better story.
Wednesday, August 3, 2011
Redshifts
Astronomers often calculate what is called redshift to determine different properties of celestial bodies, mainly their distance from us. The redshift is often related to the Doppler effect of the light that is coming to us from that body, say a star. In the same way that an ambulance siren's pitch varies to our ears when it approaches and leaves us, the light spectrum of a star varies to our eyes (telescopes) as it travels through the space. The change in wavelength of that body's spectrum determines its redshift.
So far so good. We have a simple and yet powerful concept to work with. We can effectively derive the age, distance, velocity, temperature, and mass of bodies billions of miles away from us just by looking at their light spectrum's period and amplitude. You see redshift and Doppler effect in so many astronomy papers and textbooks that even to a non-astronomer like me they become common knowledge. Something as famous and powerful as E = mc^2 or F = ma. And just as you feel a little comfortable and confident about calculating at least one thing in astronomy, here came our professor and announced the biggest misconception in astronomy textbooks: The redshift of galaxies is not due to Doppler effect, it is due to the expansion of the universe! Astronomers call this cosmological redshift! Doppler effect is responsible for redshifts in our solar system and in our own galaxy. When we look at spectra of other galaxies, their redshift is a result of the Hubble's law!
Ouch! My summer intern was calculating redshifts for galaxies and he had mentioned Doppler effect in his report. I emailed him directly from the training. They cannot get a return on investment from an Astronomy for Engineers training any faster than that! Of course, it does not affect calculations of the redshift and the results, but just the motivation behind the solution was not stated correctly scientifically.
So far so good. We have a simple and yet powerful concept to work with. We can effectively derive the age, distance, velocity, temperature, and mass of bodies billions of miles away from us just by looking at their light spectrum's period and amplitude. You see redshift and Doppler effect in so many astronomy papers and textbooks that even to a non-astronomer like me they become common knowledge. Something as famous and powerful as E = mc^2 or F = ma. And just as you feel a little comfortable and confident about calculating at least one thing in astronomy, here came our professor and announced the biggest misconception in astronomy textbooks: The redshift of galaxies is not due to Doppler effect, it is due to the expansion of the universe! Astronomers call this cosmological redshift! Doppler effect is responsible for redshifts in our solar system and in our own galaxy. When we look at spectra of other galaxies, their redshift is a result of the Hubble's law!
Ouch! My summer intern was calculating redshifts for galaxies and he had mentioned Doppler effect in his report. I emailed him directly from the training. They cannot get a return on investment from an Astronomy for Engineers training any faster than that! Of course, it does not affect calculations of the redshift and the results, but just the motivation behind the solution was not stated correctly scientifically.
Tuesday, August 2, 2011
Neutron Stars
Neutron stars are leftovers from huge beautiful explosions called Supernova. They are the destiny of the dying stars if their core mass ends up less than three Sun masses. They are very dense. What is their density? 10^12 g/cm^3. Think about that for a minute. More fascinating is that they rotate very rapidly. Can you imagine how fast they rotate?
Let's get some perspective. The Earth goes around itself once every 24 hours. Our Sun, the size of a million Earths, rotates around itself once in about 25 days. These dense stars, Neutron stars, on average have a mass equivalent to 1.5 Sun masses. How fast do you think they rotate? Like Sun? Maybe twice faster? or maybe 25 times faster, going around themselves in 1 day or so? Are you ready?
Neutron stars have a period of 0.0003 to 4 seconds. That is every 4 seconds they can rotate somewhere between once to 12000 times, while being as big or larger than our Sun! Can you imagine something that huge spin that fast? 60 times to 720,000 times a minute? Can you imagine if our Earth rotated that fast? If you cannot be amazed and fascinated by this, like our professor said today, I give up! I leave and never write or teach anything else. That is it!
Yet, these massive and rapidly rotating bodies have properties with frequencies more accurate than the best atomic clocks we humans have built to date. They are universe's most accurate clocks. I get to that property some other time.
Let's get some perspective. The Earth goes around itself once every 24 hours. Our Sun, the size of a million Earths, rotates around itself once in about 25 days. These dense stars, Neutron stars, on average have a mass equivalent to 1.5 Sun masses. How fast do you think they rotate? Like Sun? Maybe twice faster? or maybe 25 times faster, going around themselves in 1 day or so? Are you ready?
Neutron stars have a period of 0.0003 to 4 seconds. That is every 4 seconds they can rotate somewhere between once to 12000 times, while being as big or larger than our Sun! Can you imagine something that huge spin that fast? 60 times to 720,000 times a minute? Can you imagine if our Earth rotated that fast? If you cannot be amazed and fascinated by this, like our professor said today, I give up! I leave and never write or teach anything else. That is it!
Yet, these massive and rapidly rotating bodies have properties with frequencies more accurate than the best atomic clocks we humans have built to date. They are universe's most accurate clocks. I get to that property some other time.
Monday, August 1, 2011
The Skies
I am taking an astronomy class these days from 8am to 5pm! I have learned enough today that I can write about them for at least a month on a daily basis. However, now I am too tired to write about the more sophisticated lessons and historical stories of astronomy. I just go over some interesting trivia!
The class started on a sad note: that humans 40,000 years ago were much more familiar with the skies than we are. Most people used the sky at least as their clock, map, and calendar. You could ask any random person to show you a particular star or constellation on a dark sky, and that person could quickly do that. It is hard to imagine a random person these days passes this test. I myself cannot locate famous stars and planets naturally. Can you? I should work on that.
So, here are the trivia:
1) "Moon" is from the Greek word Metron meaning to measure! As it was mainly used to measure different things in old times.
2) "Clock" is a German word meaning Bell, since traditional clocks were made of bells. Remember these?
, and finally
3) Brahe was a Danish astronomer who became the first federally funded researcher. He has funny stories. Maybe I tell you sometime.
Till then,
Good night!
The class started on a sad note: that humans 40,000 years ago were much more familiar with the skies than we are. Most people used the sky at least as their clock, map, and calendar. You could ask any random person to show you a particular star or constellation on a dark sky, and that person could quickly do that. It is hard to imagine a random person these days passes this test. I myself cannot locate famous stars and planets naturally. Can you? I should work on that.
So, here are the trivia:
1) "Moon" is from the Greek word Metron meaning to measure! As it was mainly used to measure different things in old times.
2) "Clock" is a German word meaning Bell, since traditional clocks were made of bells. Remember these?
, and finally
3) Brahe was a Danish astronomer who became the first federally funded researcher. He has funny stories. Maybe I tell you sometime.
Till then,
Good night!
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