Ask a local scientist - march 2014
Question and Answer Sessions for March and April 2014
What is a nebula and can you talk more about that space poster you have?
You bet. Here's a powerpoint presentation made just for you!
What Makes up the Universe: Nebulae and Galaxies
Where are we in our galaxy?
Our sun is located on a spiral arm of the Milky Way Galaxy far from the center of our galaxy. NASA has a webpage called Solar Week that has great information about the sun and our solar system.
Facts About the Sun
How much water is there on Earth?Quite a bit, but of all the water on Earth, only about one percent can be used for drinking by humans. According to the United States Geological Service, here are some numbers you can think about:
What is a nebula and can you talk more about that space poster you have?
You bet. Here's a powerpoint presentation made just for you!
What Makes up the Universe: Nebulae and Galaxies
Where are we in our galaxy?
Our sun is located on a spiral arm of the Milky Way Galaxy far from the center of our galaxy. NASA has a webpage called Solar Week that has great information about the sun and our solar system.
Facts About the Sun
How much water is there on Earth?Quite a bit, but of all the water on Earth, only about one percent can be used for drinking by humans. According to the United States Geological Service, here are some numbers you can think about:
- If all of Earth's water (oceans, icecaps and glaciers, lakes, rivers, groundwater, and water in the atmosphere was put into a sphere, then the diameter of that water ball would be about 860 miles (about 1,385 kilometers), a bit more than the distance between Salt Lake City, Utah to Topeka, Kansas. The volume of all water would be about 332.5 million cubic miles (mi3), or 1,386 million cubic kilometers (km3). A cubic mile of water equals more than 1.1 trillion gallons. A cubic kilometer of water equals about 264 billion gallons.
- About 3,100 mi3 (12,900 km3) of water, mostly in the form of water vapor, is in the atmosphere at any one time. If it all fell as precipitation at once, the Earth would be covered with only about 1 inch of water.
- If all of the world's water was poured on the contiguous (lower 48 states) United States, it would cover the land to a depth of about 107 miles (145 kilometers).
- Of the freshwater on Earth, much more is stored in the ground than is available in lakes and rivers. More than 2,000,000 mi3 (8,400,000 km3) of freshwater is stored in the Earth, most within one-half mile of the surface. But, if you really want to find freshwater, the most is stored in the 7,000,000 mi3 (29,200,000 km3) of water found in glaciers and icecaps, mainly in the polar regions and in Greenland.
How many stars are there in space?No one knows how many stars exist, but the number would be staggering. Our universe likely contains more than 100 billion galaxies, and each of those galaxies may have more than 100 billion stars.
Stars, Stars Information, Facts, News, Photos -- National Geographic
science.nationalgeographic.com/science/space/universe/stars-article/
Hubble looking at the universe on a dime
The 100 hour, 10-day picture
Hubble Telescope Deep Field View 2012
What does a million, billion, or trillion look like?
Stars, Stars Information, Facts, News, Photos -- National Geographic
science.nationalgeographic.com/science/space/universe/stars-article/
Hubble looking at the universe on a dime
The 100 hour, 10-day picture
Hubble Telescope Deep Field View 2012
What does a million, billion, or trillion look like?
How big was Thea compared to the original Earth?
Astrophysicists believe about the size of Mars
dailygalaxy.com
Astrophysicists believe about the size of Mars
dailygalaxy.com
Where does the rain come from? The Water Cycle can explain that!
How did humans come to be if all the dinosaurs were extinct? So what did we evolve from?
This is another really big question. In middle school we spend several months talking about the origins of Earth and evolution of life on our planet.
To give you a short answer, let's start with scientist's hypothesis about why the dinosaurs became extinct:
Why are there craters in (on) the moon and how did they get there?
Meteors and other rock-type space stuff hit the surface of the moon and because the moon doesn't have an atmosphere (a layer of air) to cause friction with meteors and burn them up, they are able to hit the moon pretty hard. The crater is the scar on the surface of the moon from the impact. Happens all the time. Earth gets bombarded by meteors and rock-type space stuff all the time too but most of these burn up in our atmosphere (we see them sometimes, and we call them shooting stars).
A NEW CRATER APPEARS ON THE MOON DECEMBER 18 2013
This is another really big question. In middle school we spend several months talking about the origins of Earth and evolution of life on our planet.
To give you a short answer, let's start with scientist's hypothesis about why the dinosaurs became extinct:
- A meteor hits Earth and causes a huge cloud of dust which spreads into the atmosphere and around the globe.
- This reduces the temperature globally, affecting plant growth and cooling down the weather.
- Dinosaurs were cold blooded, one of the contributing factors to their extinction is their inability to maintain body heat or keep their eggs warm enough all the time.
- This marks the rise of the mammal, animals classified by live birth, nursing, body hair and being WARM BLOODED (that's a big one)
- Remember that in science, evolution means change over time. So over several million years (think about that time scale for a moment): small mammals grew in size (as food became more available as the dust settled from the atmosphere letting the sun shine on animals and plants); some mammal that is the great ancestor to current chimpanzees, gorillas, orangutans and humans began to walk on two legs more often; then this ancestor decided walking on two legs was great for survival and walked on two legs all the time; and then this ancestor's brain started growing to accommodate all these new sensory and survival requirements. Evidence suggests that there were many humanoid species over time but only those that "evolved" the body and brain changes would have offspring that survived and thrived. This is why there are still chimpanzees AND humans. We are different tribes of the same ancestor that made choices about which "adaptations" were valued.
- The theory of evolution is based on the observations that species change to best adapt to their environment to ensure survival. Humans are still evolving, recent studies of brains are finding that the way your brain is organized is slightly different than the way your grandparents' brain are organized. That's only two generations!
Why are there craters in (on) the moon and how did they get there?
Meteors and other rock-type space stuff hit the surface of the moon and because the moon doesn't have an atmosphere (a layer of air) to cause friction with meteors and burn them up, they are able to hit the moon pretty hard. The crater is the scar on the surface of the moon from the impact. Happens all the time. Earth gets bombarded by meteors and rock-type space stuff all the time too but most of these burn up in our atmosphere (we see them sometimes, and we call them shooting stars).
A NEW CRATER APPEARS ON THE MOON DECEMBER 18 2013