Big Quake Strikes Central Mexico, Killing 225 People

A.O.W. #6

Week of 10/02/2017

Big Quake Strikes Central Mexico, Killing 225 People

A magnitude 7.1 earthquake struck central Mexico on Tuesday and killed more than 225 people.Thousands came out into the streets in panic.Earthquakes are measured by magnitude on the Richter scale, which runs from 1 to 10. The higher the number on the scale, the larger and more damaging the earthquake.The earthquake comes less than two weeks after another quake killed 90 people in the country's southern states. Mexicans also spent today remembering a 1985 earthquake that killed thousands of people.

Buildings Fall In Capital Of Mexico

Dozens of buildings fell or were damaged in parts of Mexico City and nearby states. Millions of people live in these areas.Graco Ramirez is the governor of Morelos, a state to the south of Mexico City. Sixty-nine people were killed in his state.Francisco Chavez is a spokesman for the Puebla state Interior Department. He said that at least 43 others died in Puebla.Governor Alfredo del Mazo said that 13 people died in his state, the State of Mexico.In Mexico City, the capital of Mexico, 93 people were killed.

Rescue Workers Pull Woman From The Rubble

Rescue workers rushed to the site of damaged or collapsed buildings in the capital. Reporters saw onlookers cheer as a woman was pulled from the rubble.Rescuers immediately called for silence so they could listen and hear others who might be trapped.The quake caused buildings to sway back and forth in Mexico City. People throughout the city fled from homes and offices. Many remained in the streets for hours, fearful of returning to the structures.Car alarms sounded and traffic stopped on the iconic Reforma Avenue.The U.S. Geological Survey is an organization that studies earthquakes. The group said the magnitude 7.1 hit at 1:14 p.m. in Mexico and it was centered near the Puebla state town of Raboso. This is about 76 miles southeast of Mexico City.Puebla Governor Tony Gali tweeted that there had been damaged buildings in the city of Cholula. This included collapsed church towers.

Mexico's History With Earthquakes

Earlier in the day workers across the city practiced drills. They did this on the anniversary of the 1985 earthquake, which was a magnitude 8.0 shake. That earthquake killed thousands of people and caused massive damage in large areas of Mexico City.

Stories From The Earthquake

Market stall vendor Edith Lopez is 25 years old. She said she was in a taxi a few blocks away when the quake struck. She said she saw glass bursting out of the windows of some buildings.

Local media showed video of waves rocking up and down the city's normally calm canals of Xochimilco. Boats in the canal bobbed up and down.Mexico City's international airport stopped operations and was checking for any damage.Much of Mexico City is built on what used to be a lake. Because of this, the soil is soft and can turn to liquid during earthquakes. This can cause stronger effects from earthquakes centered hundreds of miles away.

Who Felt The Quake?

The new quake appears to be unrelated to the magnitude 8.1 incident that hit September 7 off Mexico's southern coast. That earthquake also was felt strongly in the capital.Seismologists study earthquakes and their epicenters. The epicenter of an earthquake is where it begins. U.S. Geological Survey seismologist Paul Earle measured the distance between the epicenters of the two quakes. He observed that they occurred 400 miles apart and most aftershocks are within 62 miles.Earle said that in the past one hundred years there have been 19 earthquakes with a magnitude of 6.5 or larger near Tuesday's event. There are about 15 to 20 earthquakes this size or larger each year worldwide.Early studies show that more than 30 million people would have felt some shaking from Tuesday's earthquake. The U.S. Geological Survey predicts a lot of damage and lost lives.

A.O.W. #7

Week of 10/09/2017

What is the Difference between a Galaxy and a Solar System?

The sun warms us each and every day. But did you know it is also a star? All the stars in the night sky are suns too.These stars, or suns, can have their own solar systems. A solar system is a group of planets that move around a sun. A single solar system can contain hundreds of planets.There is a difference between a solar system and a galaxy. A galaxy is a huge collection of gas, dust and billions of stars and their solar systems. Galaxies are held together by gravity, which keeps planets and stars from simply floating away.Our sun is just one ofat least 200 billion stars in our galaxy, which is called the Milky Way. Oursolar system is also just one of many solar systems in this galaxy.Even the Milky Way is just one of many galaxies.Scientists believe there are hundreds of billions of galaxies in the universe.The Milky Way is part of a group of about 30 galaxies called the Local Group. Our nearest big neighbor is called the Andromedagalaxy.

Spiral Galaxies And Other Shapes

Our galaxy, the Milky Way, is shaped like a spiral.A spiral is a shape that curls around a center point. The Milky Way is a type of spiral that looks a bit like certain kinds of seashells.

About 2 out of 3 galaxies in the universe are also shaped like spirals. Some galaxies are shaped ellipses, or stretched circles. A few look like toothpicks or rings.How do we know what other galaxies looklike if they are so far away? Scientists can see distant galaxies thanks to the Hubble Space Telescope. This is a telescope in outer space that can see outside of our galaxy. It was made by NASA, a lab in the U.S. that builds machines to study space. The Hubble Space Telescope has found many thousands of galaxies, of all sizes, shapes and colors.Our galaxy, the Milky Way, has hundreds of billions of stars. It also has at least 10 times as much dark matter as all the stars and gas put together.

Dark Matter: We Can't See It

Dark matter is the opposite of bright matter.Bright matter is what we can see with our eyes or with the help of telescopes. It includes bright objects such as planets, stars and galaxies.

Dark matter is what exists around all those bright objects. We know it exists because we can measure how much itpulls on other objects in the universe. We just can't see it.

Black holes are one kind of dark matter. Objects that are just a little too small to be stars are another kind. They are too small to make any light.Scientists believe most dark matter is made up of tiny pieces of matter. These pieceshave not been seen or studied yet.

Galaxies Headed For Collision

Galaxies often crash into each other. The Milky Way itself is on a collision course with our nearest neighbor, the Andromeda galaxy. There's no need to worry, though. The crash won't happen for around another 5 billion years.Even if it happened tomorrow, you might not notice. Galaxies are very long and stretched out, so usually it's only their ends that bump together. Most planets are nowhere near the ends of their galaxies. When galaxies bump into each other, the planets often don’t get close enough to crash.

A.O.W. #8

Week of 10/16/2017

Explainer: How do you measure a sea’s level, anyway?

There are about 330 million cubic miles of water in the world oceans today. Early in our planet’s 4.5-billion-year history, water slowly collected in the low areas of the planet’s surface. These areas became ocean basins. As more water gathered there, the water level got higher and higher.

This height is called the sea level. It is related to the total amount of water in the oceans. Like a bathtub, the more water is in the oceans, the higher the sea level.

The sea level is also linked to the shorelines. As water levels rise, areas that used to be land get covered in water. As a result, the shorelines shrink inward.

Throughout history, the climate, the average weather conditions on Earth, has constantly changed. The sea level has gone up and down in response. As oceans warmed during one period of the planet's history, water expanded and the sea level rose. This is called thermal expansion. As the Earth continued warming, ice sheets and glaciers melted, adding more water to the oceans, which caused sea level to rise further.

Tide Gauges Are Like Large Pipes In The Ocean

People have been keeping track of the sea level for about 200 years. Until recently, this was done with devices called tide gauges. Tide gauges are anchored to structures along the coastline, such as docks. They record changes in the water level.The oldest tide gauge in the world is on the coast of Poland. It was installed in 1808. In the United States, there are two tide gauges that have been measuring the sea level since 1856. One is in New York, and the other is in San Francisco. There are newer tide gauges as well, many of which were set up in the past 50 to 75 years.

A tide gauge looks like a large pipe inserted into the ocean. It has a float inside that moves up and down as the water level changes. As the tide rises and falls each day, these gauges record those changes in water level.These instruments were not set up for the sake of scientific research. They were used to measure the depth of the water so that ships could enter and leave ports safely. As time went on, however, people noticed that the gauges were measuring long-term changes.

Coastal Areas Are Sinking And Rising

Each of these official tide gauges keeps track of sea level at a particular coastal location. Many coastal areas are not stable, however. Some are sinking, such as New Orleans or Venice. Others, like Alaska and Scandinavia, are rising. Each tide gauge keeps track of how the sea level is changing compared to the land on which it is anchored.Some gauges are on coasts that are rising and some are on coasts that are sinking. That means that sea level changes are different from place to place. In parts of Alaska, the land is rising faster than sea level. As a result, the tide gauge actually records a drop in sea level compared to the land.Overall, the sea level has risen nearly seven inches in the past 100 years.In 1993, two satellites were launched into space. They were put into orbit around the Earth. Like our moon, they fly in circles around the planet.

Creating A Standard Sea Level

The satellites use radar technology to measure the level of the ocean from space. Unlike tide gauges, the satellites do not move up and down. This means they can provide standard measurements of sea-level changes.The satellites have measured a global sea-level rise of 3.2 millimeters per year since 1993. That rate is about 12 inches per 100 years.Maps of both land and sea use the sea level as a base. Land elevations and ocean depths are measured against the sea level.However, the sea level is slightly different in different places around the world. This is due to differences in water temperatures, currents, atmospheric pressure and wind. These local differences make describing the sea level more complicated.In order to simplify things, a standard sea level was established. It was based on sea level averages around the world. This standard was called the North American Vertical Datum (or NAVD). It is now the sea level used by all maps.So what does it mean when a dock, highway or building is listed as “20 feet above sea level"? Now you know. It means "20 feet above this official North American Vertical Datum."

Gary Griggsis the director of the Institute of Marine Sciences at the University of California, Santa Cruz.

A.O.W. #9

Week of 10/23/2017

Should There be 13 months in a Year?

A month can start on any day of the week and last anywhere from 28 to 31 days. Sometimes a month is four weeks long, sometimes five and sometimes six. All this can be hard to keep track of, which is why people buy a calendar with new dates every year.Today's calendar is mostly a combination of the Roman lunar calendar and the Egyptian solar calendar. It was created after a discussion between the Roman leader Julius Caesar and Cleopatra, the queen of Egypt.The Egyptians knew that the year is roughly 365 days long. They were able to measure the time of the year based on the Nile river's waters. They used "nilometers," which were structures that filled with water from the Nile and kept track of the river's height. Sincethe Nile flooded to the same level about the same day every year, theEgyptians could use the nilometers to predict the seasons.The Egyptians also figured out that the year isn’t exactly 365 days long. They added an extra day every four years, just to make sure the calendar year matched up with the seasons. In other words, they invented the leap year.

Caesar Updates Roman Calendar

This was all great news to Caesar. He knew that the Roman calendar wasn't quite right. At that time, the Roman calendar year, which was based on the phases of the moon, was only 354 days long. So, the Romans created theJulian calendar by adding the 11 missing days and a leap day in February.But even this calendar was not exact. By 1582, less than 500 years ago, Pope Gregory came up with a new calendar. Theleader of the Roman Catholic Church hadrealized that everyone was worshiping the holy days on the wrong dates. He made a few changes to realign the year with the seasons and created the Gregorian calendar, which is what we use today.

Throughout history, there have been a number of people who tried to create a new calendar. One of them wasMoses B. Cotsworth, who worked for the British railway. The Gregorian calendar made it difficult for him to do accounting for the company, so he thought of a better system.In 1902, he presented a design for a calendar of 13 months. Every month was exactly 28 days, no more, no less.This meant the dates were all standardized as well. Regardless of the month, the 5th was a Thursday, and the 1st was always a Sunday. The 10th was always a Tuesday, and there would be a Friday the 13th every single month.

"Sol" Name Is Appropriate

All the month names would stay the same and an additional 28-day month would fall between June and July. This extra month would be called "Sol," after the summer solstice, which is the longest day of the year.Thirteen months of 28 days each make 364 days in a year. To make it 365, Cotsworth added a new holiday after December 28 called ”Year Day,” a floating day, not part of any month. It would be a global rest day.Cotsworth toured the United States giving talks about his calendar's many benefits, but he couldn't find many takers. He did attract the interest of one of the world's wealthiest and most successful men, George Eastman, the founder of Kodak.The Eastman Kodak company adopted the 13-month calendar in 1924 and continued to use it until 1989. Kodak employees didn’t observe "Sol" or “Year Day," but the company's schedule was organized into 13 "periods."

Several Proposals Before Legislators

George Eastman tried to convince the rest of the world to make the switch. Eastman and Cotsworth even presented the calendar to the U.S. Congress. At one point The League of Nations, the world government of countries of the time, was considering 185 different calendar designs. Cotsworth and Eastman's proposal was one of a few finalists, but the league did not make a decision. In 1939, World War II broke out, which made the project much less important.

No one has really tried to change the calendar since then. But there’s no reason we can’t take our vacations in Sol and celebrate Year Day.

A.O.W. #10

Week of 11/06/2017

"Minecraft" and Museums Let Kids Explore and Create!

The video game "Minecraft" gives sweeping creative freedom to its players. That's the beauty of it! The game remains wildly popular more than eight years after its release. All players use the same resources and tools. But they come up with totally different ideas about what to build and how to build it. They also can expand on their first creations as the days and weeks go by. Players build all kinds of designs — from ancient forts to modern skyscrapers. The only real limit on players is their own imagination.

"Minecraft" And Museum Day Live!

In this way, "Minecraft" is much like a nationwide museum event that encourages exploration and creativity.The Smithsonian Institution started this annual event, which is known as Museum Day Live! This year it takes place on September 23. More than 1,000 different museums across the country will participate. And "Minecraft: Education Edition" will be available online, too. Children and adults alike will be able to create their own worlds inspired by the museum exhibits they saw."Minecraft" is the perfect game for Museum Day. Museums are full of treasures just waiting to be discovered. What you make of those treasures is entirely up to you — just like in "Minecraft"!