Recalling Challenger

Have 30 years really passed since the Challenger space shuttle exploded?  That time period represents a generation.  I can see that sad Tuesday in my head quite well even now.  I was 15 years old at the time.  My 10th-grade English teacher had wheeled a television into our classroom so that we could watch the launch.  Though shuttle missions had become less of an event since Columbia flew its maiden voyage in 1981, and Challenger was on its 10th mission on that dreadful day in 1986, the Challenger lift off we watched 30 years ago was special because of crew member Christa McAuliffe.  She was to be the first school teacher in space, and my English teacher was giddy with anticipation just before the launch.  It's why we watched -- to see a "regular person" make it into space.

Everyone has seen the awful explosion just 73 seconds after take-off.  I will never forget my English teacher crying after it happened.  I will never forget the feeling that what I had seen was not real.  It took awhile for my 15-year-old mind to realize that I had watched seven people die.  For my parents, "Where were you when JFK was shot?" was a common question.  For people my age, "Where were you when Challenger exploded?" has been a common question.  Other events like 9/11 have followed the "when" in the question.  I remember 28 January 1986 as being one year to the day since We Are The World was recorded.  I remember that Tuesday as being just two days after the Chicago Bears made a strong case in Super Bowl XX for the best football team of all time.  Not long afterwards, I remember seeing Richard Feynman put an O-ring in cold water to demonstrate that the material comprising the O-rings was not suitable for the cold weather of the January launch.  Richard Feynman became a superstar in my 15-year-old nerdy head.

I had to look up the other names of the Challenger crew members because besides McAuliffe, I remembered only Ronald McNair.  He had a PhD in physics from MIT and a black belt in karate.  I have read some of his work on karate physics.  He seemed like a cool guy when I was 15, and even more so now.  The other crew members were Francis Scobee, Michael Smith, Ellison Onizuka, Judith Resnik, and Gregory Jarvis.  I am glad to look up the names today because remembering those who sacrificed their lives for the advancement of science is important.

Best Hail Mary Ever?

Think of the great Hail Mary passes in American football.  Staubach to Pearson at the end of '75 got the term into our vernacular.  My favorite Hail Mary was in '84 when Flutie hit Phelan to beat Miami in the Orange Bowl.  Not only was that a great game, but I was 14 years old, meaning great things happening in my life at that time would undoubtedly stand out in my mind for the rest of my life.  I loved the play so much that I devoted a chapter to it in my first book.  I saw a Hail Mary this past weekend that will rival Flutie's pass when the great Hail Mary passes are ranked again.

On Saturday night, 16 January 2016, the Green Bay Packers were trailing the Arizona Cardinals, 13-20, in an NFC division play-off game.  With just 5 s on the game clock, the Packers had one play left, but they were on the Arizona 41-yard line, and they needed a touchdown to force overtime.  I grabbed the screen image below just before the snap (click on the image for a larger view).

All pertinent information is supplied by NBC in the screen shot.  Aaron Rogers took the snap from the shotgun formation, and Arizona brought pressure.  Rogers stepped back and scrambled to his left.  It took 4.2 s for him to release his pass after the snap (click on the image for a larger view).

Look at that throw!  Rogers had a man in his face while falling back to his left as he threw.  I grabbed the screen image below from instant replay (click on the image for a larger view).

Pure athleticism and talent helped Rogers release the ball with a spiral.  You will note that he released the ball about 5.5 yards inside his own territory and well left of the left hash marks.  After spending 3.6 s in the air, Jeff Janis snagged the ball about 5 yards past the goal line (click on the image for a larger view).

I estimated that the ball travelled horizontally almost 61 yards (56 m).  Taking into account air resistance, but no wind (I do not know the weather conditions at the time of the pass), I calculated that Rogers released the pass at 56.4 mph (25.2 m/s or 90.7 kph) and 46.9 degrees above the horizontal.  Just after Rogers let go of the ball, the ball experienced a drag force from the air that was almost 22% of its weight.  Janis, who certainly deserves credit for an amazing catch, one that had to be reviewed to ensure he had possession throughout his fall to the turf, caught the ball travelling 49.0 mph (21.9 m/s or 78.8 kph).  The plot below shows the trajectory (click on the image for a larger view).

The maximum height of the ball was nearly 20 yards (18 m) above the turf.  That vertical distance represents two first downs!

After such an amazing play put the game into overtime, a coin flip fiasco gave the Cardinals first possession in overtime.  Their first play was a Palmer-to-Fitzgerald pass for 75 yards.  Two plays later, Fitzgerald caught the winning touchdown pass from Palmer.  Despite the loss, Aaron Rogers threw what has to be one of the greatest Hail Mary passes of all time.

A Day in Nottingham

My family took advantage of a beautiful day (clear skies and 0 C) this past Saturday (16 January) by hopping on a train for Nottingham.  When we were here seven years ago, we visited Sherwood Forest, but did not make it into the city of Nottingham.  We discovered on Saturday that Nottingham has a lot of offer!

Our first stop was the City of Caves.  We learned from a great guide that Nottingham has something like 500 caves below it.  Some of the caves we toured are beneath the Broadmarsh shopping centre.   I like the room in the photo below (click on the image for a larger view).

This horseshoe-shaped room stored beer for a pub called the Three Horseshoes (was this cellar the fourth horseshoe?).  A hole in the ceiling was used to warn gamblers in the room that local authorities were about to raid the pub.  The room off to the left in the above photo was dug out during World War II as a place to store documents in case the Germans made their way into England.  We also saw an air-raid shelter from World War II, though Nottingham was not hit like other cities in England.  Not far from the pub cellar are the medieval tanneries.  All fascinating to see and hear about!

We next visited Nottingham Castle, which dates to the 11th century.  But before entering the castle, I just had to pose with the Robin Hood statue (click on the image for a larger view).

My bloody left ulna is still broken, so I could not come close to holding a pulled bow like the folk legend in the statue.  Once in the castle, we especially enjoyed the view of Nottingham just outside the Ducal Mansion (click on the image for a larger view).

Nottingham Station, where we got the train, is visible left of centre behind the "British Waterways" building.  The station has a nice clock on top.

After a great day of learning about Nottingham, we were met with snow when we arrived back in Sheffield.  The city looked beautiful at night with snow on it.  Not a bad way to end a great day!

Winter Holiday in Norway

My daughters had a fortnight-long winter break from their respective Sheffield schools.  We took advantage of their break and spent ten days in Norway (21 December - 30 December).  What a beautiful country!  Most people we encountered were very friendly, almost all spoke English quite well, and public transportation made getting around easy.

We spent six days in Oslo.  That is one clean city, probably the cleanest city I've visited.    Even the subway stations are immaculate.  In late December at approximately 60 degrees latitude, there are only about six hours between sunrise and sunset, so we had to make the most of the daylight.  We visited a Christmas market (click on image for a larger view).

We enjoyed great food, including wonderfully-prepared fresh fish and traditional Norwegian fare on Christmas Eve.  One of many new experiences for me was ice skating on an outdoor rink (click on the image for a larger view).

Not bad form for a nerdy physicist, huh?  Well, perhaps I could use more practice!  I've not ice skated much in my life, but I've got more appreciation for those who zoom on the ice, be they figure skaters or ice-hockey players.  We toured the Oslo Harbour and walked many streets.  Part of Boxing Day was spent at Frogner Park.  The photo below shows the monolith, one of many cool statues in the park (click in the image for a larger view).

Boxing Day in 2015 will remain in my memory for a long, long time.  When I first learned that my family would return to Sheffield for my second sabbatical, I had the idea of spending Christmas in Norway.  Not only have I always wanted to visit Norway, I wanted to be in snow during the Christmas holiday.  For about a year, my family has been anticipating skiing in Norway.  Boxing Day was our last full day in Oslo; we were headed to the ski resort at Hemsedal on the following day.  I took my daughters to a playground near the home we were renting.  I've been studying friction between shoes and sports surfaces since my sabbatical research commenced.  I wish I had just a bit more friction on Boxing Day because I slipped at the playground and broke my left ulna.  No skiing for me!

So after a year looking forward to skiing in Norway, I had to sit on the sidelines and watch my wife and daughters hit the slopes.  But accidents happen, and there are definitely no do-overs in life.  Accepting reality is sometimes easier said than done.  As much as I hated missing out on skiing, I would have felt ten times worse had my wife or one of my daughters been the one sitting in the lodge.  I'm glad they had fun!

I still enjoyed Hemsedal.  It was a winter wonderland.  I witnessed beauty in nature almost everywhere I looked.  My family did some dogsled riding while there.  I was unable to drive, but thoroughly enjoyed the ride.  The scenery was breathtaking (click on the image for a larger view).

I learned a great deal about how the dogsleds work, what the dogs are like, and got some great ideas for physics problems.

It was tough leaving Hemsedal, knowing that I did not get to ski, and wondering if I would make it back at some point in the future.  The photo below shows my last look at the ski resort (click on the image for a larger view).

Beautiful, isn't it?  Despite my broken arm, I loved being in Norway over the holidays.  Sometimes life doesn't go exactly like you want it to go.  What's important is making the best of life, not only for yourself, but for those around you.  We get one shot at life.  Make the most of each and every day!