Another winter collage

Can We Make It to Mars?

Home Sweet Home (NASA Photo)

I watched a NOVA show entitled, "Can We Make It to Mars"? hosted by astrophysicist Neil deGrasse Tyson. I have been watching quite a few of these shows in the past two years. Maybe because there are more of them.

What I carry away from these shows, is just how wonderful and special Planet Earth is. I have said this before but I truly think some people believe we are just a couple of years away from boarding a spaceship or walking thorough a wormhole to some pristine and abundant planet to start over again.

Boy, are they wrong. They seem to have no idea how dangerous and inhospitable space is for us earthlings, including plants and other animals.

Besides not having oxygen to breathe and being freezing cold, space has these dangers.

Danger One: Meteoroids.
A pea-sized meteoroid can travel at 16,000 miles per hour and pierce the hull of a spaceship. The space programs have lost spacecraft because of bombardment by meteoroids. NASA is developing a hulll than can hold-up to meteoroid bombardment.

Danger Two: Zero Gravity
In zero gravity, sure you can fly but you also lose bone mass and muscle strength.

Danger Three: Cosmic Rays
Yeah, this isn't Flash Gordon's cosmic rays. These bright flashes of light pierce spaceships and astronauts brains (yes, brains) to deliver very heavy doses of radiation predisposing the body's cells to develop cancer. And the astronauts know when they go up into space, the are increasing their chances.

After I watch a show, or read a article or book on the topic of deep space travel, I am convinced humanity is quite insane. We have a beautiful home planet that supports us humans and abundant life, yet some of us dream of hurling through space at mind-numbing speed, picking up radiation and eating food that was cooked and stored several years before.

I highly recommend watching, "Can We make It to Mars?'". It makes me appreciate the home we have in new ways.

And since I plan on staying put on my home planet, I fight to save it.

Photo credit: Image created by Reto Stockli with the help of Alan Nelson, under the leadership of Fritz Hasler (NASA)

http://www.birdcount.org

Circumpolar Stars in the Night Sky

stars in the constellation Cassiopeia

I don't know what it is, but winter makes me look up. When I arrive home after dark, I often find myself looking up at a clear, cold night sky. The stars always seem more sparkling and brillant in the winter sky. And a night sky seems clearer.

When I was in junior high, I used to sit on my front steps, with a star map in hand, and pick out all the constellations. I had a very simple book of star maps for each month. I wish I still had that book, but it disappeared somehow.

After weeks of looking in a cold night sky, I offer this information on star gazing. As always I focus on the basics you need to know to amaze your friends and yourself with your natural history knowledge.

Circumpolar is Latin for "around the pole".  Circumpolar stars are any stars that appear to circle around the Earth's north or south poles.  Each "pole" or hemisphere has its own set of constellations. These constellations always appear in the sky. They never sink below the horizon. They can be seen no matter what the season.

North Pole - the Northern Hemisphere 

The northern hemisphere's constellations circle around the North pole. The North Star is almost directly over the North Pole. Therefore, the northern circumpolar stars seem to circle the North star.

In the Northern Hemisphere, there are only 6 such constellations (above lat. 40 degrees N). The designation of 40 degrees north latitude passes through Philadelphia, Columbus, Ohio, and just south of the northern California border.  The constellations are:

• Ursa Minor  (the Little Dipper or the Lesser Bear)
• Ursa Major (the Big Dipper or the Great Bear)
• Cassiopeia (the Lady in theChair - the constellation shaped like a "W"
• Cepheus (the King)
• Draco (the Dragon)
• Camelopardalis 

Just six? That's right just six. 

And FYI:

South Pole - the Southern Hemisphere

 Southern hemisphere constellations don't circle around a star, because there is no "south star'. The point where it would be if it existed is called the South Celestial Pole. The longest axis of the constellation Crux, the Southern Cross points almost directly to the spot where the "south star" would be if it existed.
In the Southern Hemisphere, there are 11 constellations which circle the south celestial pole. They tend to be smaller than their northern counterparts, so there are more of them.  The constellations are:

• Toucan
• Southern Cross
• Octans
• Apus
• Triangulum Australe
• Musca, Chameleon
• Volans
• Mensa
• Reticulum
• Hydrus
• Pavo

By knowing the circumpolar stars you will know the main constellations. Then it will be easier to pick out the new ones as the seasons change. A star chart is a map of the night sky. Very simple ones show the biggest, brightest stars. More complex charts show hundreds of stars and celestial bodies.

Star maps are available in astronomy magazines.  Sky and Telescope has a weekly "sky-at-a-glance" feature on its website.  This same website has many beginning star-gazing how-to's.

Wikipedia has a cool rotating circumpolar graph and a good explanation of circumpolar stars.

Keep looking up.

Photo credit: NASA Planetary Photo Journal Collection. IRAC Image: NASA/JPL-Caltech/Harvard-Smithsonian CfA/ESA/STScI Visible Light Image: NASA/JPL-Caltech/Harvard-Smithsonian CfA/DSS