Share it! Science : September 2015

Tuesday, September 29, 2015

Water on Mars?!

With NASA's big announcement about evidence of water on Mars and this past weekend's Supermoon Eclipse, I just can't stop thinking about space! So what is the big deal about water on Mars? Haven't we been talking about evidence of water and ice on the red planet for the past few years?


This announcement is slightly different, but immensely more important. Evidence of ice, or water existing on Mars in the past has been common, but this time around the evidence is pointing to water intermittently flowing on the planet in present day.

In order to determine if there is life as we know it on other planets NASA scientists have followed evidence of water as their guide. Living things need water, so it stands to reason if you find water, you could also find life.

Mariner 9, launched in 1971, was the first to identify evidence of water on Mars when it transmitted images of riverbeds, canyons, erosion and fog back to Earth. Mariner 9 was the first artificial satellite of Mars, and photomapped 100% of the martian surface from 1971-1972. 

Scamander Vallis from Mariner 9. By Jim Secosky, NASA image.  [Public domain], via Wikimedia Commons
The Viking program further revolutionized our thinking about water on the red planet. The Viking spacecraft were the first to land safely on the surface of Mars. Both Viking 1 and Viking 2 reached the planet in 1976. The two pairs of lander and orbiter systems collected scientific data and photographed the surface in addition to completing biological experiments aimed to determine whether their was life on Mars. In the process the Viking landers discovered many geological features that further indicated the presence of water historically on the planet, such as deep valleys and valley networks in addition to erosion on the bedrock.
Image from Viking program. By Jim Secosky, modified NASA image [Public domain], via Wikimedia Commons
Investigation and evidence building toward the discovery of water on Mars continued throughout the next few decades with the Mars Global Surveyor (data on mineral composition), Mars Pathfinder (temperature readings and evidence of clouds and maybe fog), Mars Odyssey (evidence of vast regions of ice under the surface of Mars), Phoenix Mars Lander (confirmed evidence of water ice), Mars Rovers- Spirit and Opportunity, and finally the Mars Reconnaissance Orbiter (evidence of hot springs, heavy precipitation, and hydrated salts causing dark streaking).  

Frost at landing site. By Roel Van der Hoorn [Public domain], via Wikimedia Commons
Mars Odyssey Image by Jim Secosky, modified NASA image. 

The announcement of present day water on Mars comes from data from the Mars Reconnaissance Orbiter. Spectrometer readings showed hydrated salts that coincide with streaking noticed on the surface. The concentration of salts would lower the freezing point of briny water so that it could flow as a liquid. This is the same principle in place on icy roads in the winter, salt lowers the freezing point of the water so that the road is not coated with a layer of ice. The dark streaking on the surface showed how the salty water flowed downhill during warmer temperatures, and the streaks lightened during cooler temperatures indicating that the flow has slowed or stopped. The liquid is most likely just under the surface and wicking to the surface causing the streaking patterns. This evidence led to NASA's big announcement about water on Mars.


This announcement is just another step towards NASA's Journey to Mars, a mission to send humans to Mars in the 2030's, a goal outlined in the NASA Authorization Act of 2010 and in the U.S. National Space Policy, also in 2010. 

Mars Streaks. By Jim Secosky modified NASA image [Public domain], via Wikimedia Commons

There are so many ways to use this historic announcement to raise interest in space education. NASA has a wealth of information and teaching resources that you will in the resources section below. You can also keep up with all things NASA at home or in the classroom with NASA TV, a live stream on YouTube.

Read more:


Mars Books for Children: (affiliate links, click image for book info)


 

Resources:



Monday, September 28, 2015

Groovy Lab in a Box Sweepstakes!

Lunar Launch and STEMists
This post contains affiliate links, see disclosures tab for details

Calling all STEMists! What is a STEMist? A kid that is wild about Science, Technology, Engineering and Math! If this describes someone you know, you won't want to miss Groovy Lab in a Box's subscription giveaway!

From now until October 15th, 2015, you can enter to win a year's subscription to Groovy Lab in a Box (valued over $287). Groovy Lab in a Box sends a box of fun, hands-on, STEM activities to your mailbox each month. Each box includes several investigations that lead to a hands-on engineering design challenge.

The engineering challenge requires your STEMist to apply what they have learned from the investigations and their own critical thinking skills to complete. Everything you need for the activities is included in the box, with supplemental material like videos and interactives on their website through the Beyond...in a Box web portal. Visit their website for more details about this awesome subscription service. 

Click here to enter to win a one-year subscription from Groovy Lab in a Box!

Good luck!  

One-year subscription giveaway Groovy Lab in a Box

Friday, September 25, 2015

Science Lessons for National Dog Week

©SBF 2015
Did you know that it was National Dog Week? You probably know a lot about your furry pal, like her favorite toys and treats, or his favorite place go for a walk. Although we are pretty familiar with dogs behavior and habits, how much do you actually know about the science of your dog?

Did you know, for example, that your dog's nostrils work independently of one another so they can better pinpoint scents? Or that when your dog looks at you, the level of the hormone oxytocin (the "love" hormone) in its body rises? Yes, all true. What else can we learn about the science of dogs?


A dog's sense of smell is one of its most amazing senses. For all sorts of fascinating facts and links to lessons about dog science, check out Science Netlinks- Dogs Sense of Smell.

If you are into learning about recent scientific research, visit Science Daily's site on dogs. You'll find that recent studies have determined a lot about dog and cat evolution. Very interesting stuff!

From genetics and breeding to pet care and the Iditarod sled race, there is a lot to learn about dogs. Check out the following links for all sorts of lesson plans and science activities for school or home about man, woman and children's best friend!

Resources:

Book suggestions for scientists and dog lovers (affiliate links, click images for more information)

 

Tuesday, September 22, 2015

Changing Seasons: So Much More Than Temperature!


Happy Autumnal Equinox! Autumna-wha? More on that later, just know today is the official beginning of the fall season!

Do you know what causes the changing seasons? I'll give you a second to think about it.... Got it? 


Did you say the seasons change as Earth moves closer and further from the sun? How good do you feel about that answer?

Hate to tell you, but that is incorrect. The good news is- you are not alone. This is probably one of the most pervasive science misconceptions we face. Just remember this- it's all about that tilt.

For those of us who have taken a science teaching methods course, this is probably a familiar topic. An interesting video was made a while back called, A Private Universe, explores these misconceptions. In what is now a well-known opening scene, Harvard students on their graduation day are asked what causes the Earth to have seasons. Although you have to purchase this video to see it in its entirety, here is a snippet. 


You quickly begin to see that regardless of a high quality education, science misconceptions lurk!

[If you are a teacher, I'd recommend getting your hands on this video. Despite being a bit dated (if you are wondering why the people are dressed the way they are, you must be under 30) the problem still rings true today. Misconceptions are hard to break, even after evidence has been presented otherwise.]

Harvard students take note: It's all about that tilt. The Earth rotates on its own axis as it revolves around the sun. Imagine the Earth is a cherry tomato and we put a skewer through the center. The skewer is the Earth's axis. This axis does not stand perfectly upright, it leans to one side. (Scientists believe at some point we were hit with something big that knocked us off kilter.) Now, maintaining your angle of axis, revolve your skewered tomato around the "sun"- a basketball perhaps. Is the same part of the tomato leaning towards the sun?

by-woodleywonderworks Flickr Creative Commons
As the planet revolves around the sun, in what is almost a perfectly circular orbit, there are points of time when the Northern hemisphere receives more direct sunlight than the Southern hemisphere. At this time of the year, the Northern hemisphere is experiencing summer, the Southern hemisphere is experiencing winter, and vice versa. For a great graphic illustrating this concept visit NASA's Space Place page on seasons.

Ok, so what about that whole "Autumnal Equinox" thing? There are 2 points in the year when the hemispheres receive equal amounts of sunlight because for just a short period of time the Earth is "upright" rather than tilted, in relation to the sun. Today we will have the equal amounts of daylight and night time- about 12 hours each. You may have noticed equal and equinox share the root- equ meaning similar. The second equinox is in the springtime, or the Vernal Equinox.

Below are some resources and activities to help students understand the seasons better, beyond the seasonal changes we can observe in nature. Pop Quiz: What are you going to remember? Yup, it's all about that tilt. (See? You could have gone to Harvard too!)

Resources for Teaching and Learning About the Seasons:
   

Monday, September 21, 2015

Observe the Supermoon Eclipse- September 27th, 2015


Solstice Lunar Eclipse (NASA, 12/21/10) NASA's Marshall Space Flight Center
Supermoon? Blood moon? Eclipse? It's only a few nights away- Sunday, September 27th, 2015. You'll want to try to see it because it won't happen again for another 18 years...but what does it all mean and how can you view it?

This video from NASA very succinctly and clearly shows what it means to have a "Supermoon" and a lunar eclipse.



Lunar eclipses are a great opportunity for star gazing. They are more "user friendly" than solar eclipses for several reasons. One is that you don't need protective eye gear to enjoy one! Another is that they are far more common because the shadow the Earth casts on the moon is much larger than the shadow the moon casts on the sun. This will be the fourth lunar eclipse in the past 2 years. 

"Pink" Full Moon and Partial Lunar Eclipse on April 25, 2013. image: NASA Goddard Photo and Video

Ok, we've got the supermoon and eclipse portion figured out- blood moon? That sounds ominous! The term, as far as science is concerned, has to do with the orange-red color of the moon during an eclipse. There are religious beliefs about the "blood moon" and its connotations, but we won't touch upon those here.

The moon turns this reddish color for the same reason we see these colors in sunsets and sunrises. The Earth's atmosphere works like a lens with a filter on it. It bends the red wavelengths of light and scatters the blue wavelengths. 

Get Ready for the Solstice Lunar Eclipse! (NASA, 12/19/10)
I hope you can get out and view at least part of the eclipse on Sunday, September 27th. For all sorts of information on when to look, check out this article from Earth Sky. The total eclipse begins at 2:11 Universal Time. You can convert UT to your time zone here.

Three of my favorite books for sharing the night sky with children and learning more myself are: (affiliate links) 
Chet Raymo's 365 Starry Nights : An Introduction to Astronomy for Every Night of the Year
H.A. Rey's The Stars
H.A. Rey's Find the Constellations

 



If you'd like to go high tech another excellent tool for orienting yourself to the night sky is Google's Sky Map app. With the app you simply hold your phone or device up toward the sky and it shows what you should be seeing in that location. However, I'd urge you to turn off your gadgets once you know what you're looking at and just enjoy!

If you like astronomy topics you might want to read my other posts that involve the sky and beyond by following this link.

Read more:
(affiliate link)
 

Friday, September 18, 2015

Glimpse of the Garden: Week 25, A Race Against Time


This post contains affiliate links, see disclosures for more details.

Tomatoes on the window seat, tomatoes on the counter, tomatoes in the freezer and tomatoes on the vine. I would love to make some pasta sauce with those beautiful Romas and San Marzanos, dice up the Costolutos and put them in jars. I would even like to roast some cherry tomatoes and pop them in the freezer for a mid-winter treat. I know what you are thinking, "Well then, less talk, more action!". Alas, you need a critical amount of tomatoes of each type before you begin to can, blanch, freeze or dry and they don't all ripen at once.
©SBF 2015
Gardening is part patience, part intense action. Here we are at week 25 of my garden adventure for 2015 and I've waited patiently for this moment to come. Once your produce is ready there is only a small window of time before it becomes overripe, or an opportunistic woodchuck, chipmunk or rabbit comes along...instead of "hurry up and wait" we're playing a game of "wait and hurry up".
©SBF 2015
So what is the rush? How can you preserve your beautiful produce to save for later instead of eating salads for the next 3 weeks? Why do you need to process it, heat it to a certain temperature, freeze it solid or dry it out?

Microbes. Microorganisms, such as bacteria, are ready to do their part in the decomposition portion of your plant's life cycle. The plant grew your produce as a way of disseminating its own seeds, not as a kind gesture or repayment for watering it all summer. Once it has grown its fruit, eventually it will spoil. Bacteria are everywhere, and can be helpful or harmful to humans. Many of the bacteria you find in ripening and rotting veggies are not the helpful kind!
©SBF 2015
What are some ways to prevent these microbes from taking over and for you to enjoy your harvest throughout the winter?

Drying or Dehydrating
Drying foods to preserve them was most likely another happy accident. The sun and wind are pretty good dehydrators. Most microbes that cause disease enjoy a moist environment to multiply in. When food is dried out it becomes an inhospitable place for those types of bacteria. You can dry produce in your oven or in an electric food dehydrator. Check out the Colorado State University Extension page for more information on drying and dehydrating your own vegetables. Electric food dehydrators can also be purchased fairly inexpensively.



Blanching and Freezing
Freezing veggies is a quick and fairly easy option to preserve them for later use. Before you freeze vegetables you should blanch them. Blanching is a process in which you heat the vegetables for a short period of time in boiling water. They are then removed and placed in an ice bath to stop the cooking process. Blanching breaks down the enzymes that are at work ripening your food. The boiling action also helps to kill any microorganisms on the food. The blanched vegetables can then be placed in freezer bags or containers and frozen for longer periods of time. Different vegetables have different blanch times. See this link for the appropriate times for different types of produce.

Canning
Although a little more labor intensive, canning is one of my favorite ways to preserve food. If you follow a recipe and work carefully then the result is safe, well preserved food that looks awfully pretty in a jar, too. I use a heat bath canner. Basically this means that after your jars are packed you boil them for a certain amount of time to destroy any harmful microorganisms and to vacuum seal your jar shut.



Recipes for canning fruits and veggies will help you to determine if you need to add anything acidic to the jars to help preserve the food. Lemon juice and citric acid are common natural additives to preserving food canned at home. Microorganisms cannot tolerate acidic environments. I will be chronicling the process of canning my tomato sauce for you in a future post- stay tuned. For some great tips and recipes for canning, you should visit the Pick Your Own site.

For tried and true canning recipes, I recommend  Ball Complete Book of Home Preserving



©SBF 2015
I'm excited this year to have produced enough tomatoes to make some sauce and can it for the winter. Slowly but surely, the tomatoes are ripening (I need 10 lbs of them). We're almost there, just some more patience. Then someday soon the tomatoes will be ripe and they will no longer wait. Time for that intense action I spoke of earlier. I will begin the job of blanching and peeling and cranking the food mill. I'll slowly simmer the sauce and then pack it into jars and put them in a hot water bath. It will be hours of work, but well worth the effort, the patience and time. 

More on the science behind food preservation:

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