Save The Date: GEMS on February 11, 2012!

We had a terrific time at the Girls Exploring Math and Science event last year on Saturday, February 19, 2011. The Museum was buzzing with lots of learning – songs about kinetic and potential energy, buzzing instruments made with straws, Popsicle sticks and rubber bands, and lots of “ah-hah” moments throughout the day!

We had a fabulous presenting sponsor in KBR and two of their engineers were our featured speakers, Rachel Amos and Elaine Jimenez. Rachel and Elaine shared with the GEMS attendees a bit about their careers in Mechanical Engineering with KBR, their education, some tips for aspiring young engineers and scientists, and even a little about what they loved about math and science as kids. Interactive booths were hosted throughout the building by students, girl scout troops and local organizations and companies - there was so much to learn everywhere you turned!

Girl Scout booths have just been accepted for GEMS 2012 and there are some exciting topics and new ideas I’m very excited to see.

We’re still accepting applications from School Groups for booths and if you’re just now considering hosting a booth with your friends or opening it up to your class for extra credit it’s time to get some brainstorming going!  

What is a topic you’d like to know more about? What have you recently learned that you would want to share with your peers?

Here are a few links to sites that might inspire you for your awesome GEMS booth! Applications for school booths can be found online here at the HMNS website.

The Library of Congress – Everyday Mysteries

PBS.org’s Zoom for kids  - this link is to the engineering section but they offer lots more if you click around

How Stuff Works - go ahead – ask how it works!

Penn State College of Agricultural Science – Food Science

Exploratorium.edu - so many cool things to explore!

I’m also including some fabulous outcomes provided by some of our super star 2011 presenters, the “Truth in Numbers” group and the Rice University Association for Women in Mathmatics both presented booths on the topic of statistics and asked visitors to participate in their experiments pulling samples and recording results!

We can’t wait to see what everyone comes up with for GEMS 2012!

Visitors were asked by the Rice University Association of Women in Mathmatics to open a funsize bag of M&M's candies and chart how many candies of each color were included.

 

 

 

Water on Mars?

On August 5, 2011, Science Magazine published a paper, announcing that astronomers had observed unusual features on the northward slopes of cliffs in Mars’ southern hemisphere. Strangely, these narrow, dark features are seasonal; they appear in spring and summer and disappear as fall approaches. So far, the explanation that best fits the evidence is that briny water sometimes flows on Mars.

Fourth Planet From The Sun

Mars, the fourth planet from the Sun, is just over half as big across as the Earth and almost one-ninth as massive. Mars takes almost two Earth years (687 days to be exact) to complete an orbit which, on average, is half again as big as ours.  However, Mars’ orbit is over five and a half times as eccentric, or out-of-round, as ours.  Unlike on Earth, then, the variation in Mars’ distance from the Sun is significant enough to influence its climate.

Similarly to Earth, Mars rotates on its axis once every 24.6 hours.  This axis is tilted by about 24.5 degrees, giving Mars seasons similar to those on Earth, whose axis is tilted by 23.5 degrees.  In its interior, Mars has no liquid outer core and therefore lacks a global magnetic field to deflect the solar wind away from its atmosphere.

Red Marble vs. Blue Marble
Creative Commons License photo credit: Bluedharma

These factors contribute to a climate where pure liquid water is highly unstable and cannot persist for long.

Due to its greater distance from the Sun, Mars is much colder than Earth.  Mars Global Surveyor measured temperatures ranging from zero to -113 degrees Celsius (32 to -170 oF).  Temperatures at the surface can be above freezing in summer, particularly in Mars’ southern hemisphere, because summertime there coincides with perihelion.  Even so, temperatures just one meter above the surface can be cooler than on the ground, as measured by Mars Pathfinder.  Nighttime temperatures at the poles can approach -200 oF, colder than the coldest temperature ever recorded in Antarctica (-129 oF).

Further, lack of a magnetic field means that Mars was unable to retain much of an atmosphere. 

Earth’s atmosphere is over 200 times as massive as that of Mars.  Although it is over 95% composed of carbon dioxide, such a tenuous atmosphere produces no significant greenhouse effect to raise temperatures on Mars.  Except at the very lowest elevations, the very thin Martian atmosphere exerts a pressure lower than the triple point of water; even on rare occasions when the temperature might be above freezing, ice sublimates rather than melting.

Why Salt Water Might Exist On Mars

Salt water, however, freezes at a lower temperature than pure water, and thus might remain liquid for brief periods on Mars.  Salt water (or brines), then, might explain observations made by NASA’s Mars Reconnaissance Orbiter, which has orbited Mars since November 2006.  Images from this orbiter’s High Resolution Imaging Science Experiment show features called Recurring Slope Lineae (RSL).  They are in Mars’ southern hemisphere, on the north (equator facing) slopes such as crater walls.  The RSLs appear in local springtime and persist until local autumn, when they vanish.  Only 0.5 meters to 5 meters wide, they can become hundreds of meters long during Mars’ southern summer.

Life Requires Water

We have always been interested in finding signs of water on planets other than Earth because life as we know it requires water to exist.  As the only other planet in our solar system with conditions even approaching ours, Mars is among the first places we looked for life beyond Earth.  The search for water, and thus possible life, has been a major goal of our robotic missions to Mars, including the Viking program in the 1970′s.

We have established that H2O exists on Mars in other phases. 

Mars’ polar caps are cold enough for dry ice (frozen carbon dioxide), but they contain water ice as well.  In 2005, the European Space Agency’s Mars Express satellite snapped a picture of an ‘ice lake’ in the bottom of a crater near Mars’ north pole. In 2008, the Phoenix lander revealed water ice in trenches dug by its robotic arm.  In 2004, the rover Opportunity took photos of water ice clouds and was also at times covered in frost, indicating water vapor had frozen onto the rover.

For liquid water, however, scientists had looked into Mars’ past.  Vastitas Borealis, a huge region between four and five kilometers lower than the mean elevation of Mars, fills much of Mars’ northern hemisphere.  It is also flatter, with craters in the Vastitas Borealis much rarer than on the rest of Mars.  Many scientists subscribe to the Mars Ocean Hypothesis, which posits that about 3.8 million years ago, Vastitas Borealis was the site of a vast ocean covering about one-third of Mars’ surface, which then either evaporated or froze into the ground as Mars’ environment ceased to support large bodies of liquid water.  For one thing, the size and shape of craters in Vastitas Borealis suggest that sublimation of water ice played a role in weathering them.  Also, there are networks of valleys resembling river systems on Earth, as if they once flowed into the ancient ocean.

A large water ocean could have persisted on early Mars

To support this ancient ocean, there are indications that Mars once had enough carbon dioxide to exert up to one bar of atmospheric pressure.  Under this higher pressure, combined with higher temperatures (due to the greenhouse effect) a large water ocean could have persisted on early Mars.  However, Mars lacks a global magnetic field; its atmosphere interacts directly with the solar wind.  This interaction would have gradually dispersed Mars’ atmosphere into space, a process we can observe today.  As the atmosphere went away, Mars would have lost its ocean due to the end of the greenhouse effect and the lower air pressure.

The existence of this ancient water ocean on Mars is not yet fully established; competing explanations such as wind erosion or liquid methane are not yet excluded.  Still, a former ocean 3.8 milllion years in Mars’ past has been our best bet for liquid water on the Red Planet.

Liquid Water on Mars Today

Until now, that is.  If confirmed by future observations, August 2011 would mark the first published evidence of liquid water on Mars today.  Yet many questions remain.  We know neither the source of the salty water, nor the precise mechanism that brings it to the surface, not to mention whether or not such water might contain germs.  So, the science we’re doing  at Mars continues, as the new questions raised make Mars an even more fascinating world to study.

Get your hands on science!

Terrence McGovern, a volunteer here at HMNS, does several chemistry shows a week to help teach the basics to our visitors. His show, geared towards both kids and adults, is a great way to see science in action.

Terrence explains the principles of density, acids and bases, and polymers in a way that makes it easy to understand no matter what your age is or your background in chemistry. A simple experiment with an egg, saltwater and freshwater helps to show how density affects whether or not items will float.

 Terrence McGovern demonstrates how density works
with the help of a member of the audience.

Terrence also shows how acid and bases can react with one another. Filling a bottle with vinegar (an acid) and placing a little baking soda (a base) in a balloon, he shows how the two react to form a gas that inflates the balloon.

 
 Chemical Reaction!

So come on down to HMNS and see one of Terrence’s many shows and learn all about chemistry.

This show is free for patrons with a ticket for our exhibition halls. For more information and show times, call the box office at 713-639-4629.

GEMS (girls exploring math and science) at HMNS this Saturday!

This Saturday the Houston Museum of Natural Science and the Girl Scouts of San Jacinto Council are partnering to bring you the annual Girls Exploring Math and Science event at HMNS! The GEMS event is open to all ages and will begin at 9 a.m. and go until noon – there’s lots to see and do so I would recommend coming early!

Thanks to our fabulous presenting sponsor KBR we are able to offer the GEMS event free with HMNS general admission for the day!! That means this event is FREE for HMNS members and the regular price of $10 for children and $15 for adult non-members for the day. There’s no need to pre-register (unless you want to avoid the box office line on a Saturday morning) so we hope you’ll grab your family and head on over to HMNS for a little fun in learning with us this Saturday! Tickets are available online here.

yahtzee

We have a great line up of Girl Scout hosted booths who will be sharing lists of really fun science and math demonstrations and activities with visitors from 9 a.m.-12 p.m. Two KBR engineers will share with us their passion for science and math and a little about how they use their skills in their job in the Mechanical Engineering Department at KBR here in Houston. Want to come up with some questions to ask our visiting Engineers about their jobs – check out this website to find out more about engineering.

Since 2011 is the International Year of Chemistry we are also including a Cool Chemistry program for GEMS participants. The Cool Chemistry program is presented by our Science on Stage presenter here at the Museum and will include exciting reactions, and liquid nitrogen demonstrations! Science on Stage can be booked to visit your school – for more information email sos@hmns.org.

5 senses

Don’t forget to visit our Community booths in the Grand Hall of the Museum during GEMS  – here’s the line up of this year’s community partners; KBR, The Houston Zoo, Swift Energy Corporation, Fisher Science EducationThe John C. Freeman Weather Museum, Downtown Aquarium, CB&I, MD Anderson, Society of Petroleum Engineers, Career Girls, Kinetic Energy, City of Houston Waterworks Education Center, Rice University Association for Women in Mathematics, The Center for Hearing and Speech, LyondellBasell and the Girl Scouts of San Jacinto Astronomy and Robotics groups.

Can’t wait to see everyone here on Saturday morning!