Science Thursdays

1st Thursday of the Month

Join Derrick Pitts the First Thursday of each month for a look into deep space! As Chief Astronomer of the Fels Planetarium at the Franklin Institute, Derrick knows his star stuff! Derrick will offer a Skywatch - what to look for in the evening skies during the month and he'll take us on a monthly trip across our Solar System - visiting a different planet every month.

New NASA Video

Check out this report on a brand new video from NASA which shows how the weather in one part of our planet affects all of us, by using elapsed satelitte images and data.

For more details and to watch the entire video;
http://www.nasa.gov/topics/earth/features/cryo_tour.html

September Sky Watch

As summer comes to a close, reduced heat and humidity allow clearer night skies while decreasing minutes of daylight bring sunset earlier every day.

Viewing at 9 p.m., most of the main constellations of the summer are still visible. This year the solar system’s largest planet, Jupiter, is well placed for easy viewing high in the southeastern sky. Jupiter will appear as the brightest object visible at night other than the moon. A good rule of thumb to use to tell the difference between planets and stars: stars twinkle but planets don’t. A small telescope will reveal Jupiter’s four largest and brightest moons, Io, Europa, Ganymede and Callisto.

Directly overhead is bright Deneb, second brightest star of the summer sky, part of the constellation Cygnus, the Swan. The stars of this group look more like a large cross than a swan. Deneb is at the top of the cross, a dimmer star called Albireo is at the foot of the cross and the two stars that mark the cross-bar are easy to see. The Milky Way, the arms of our galaxy as seen from the earth, run right along the long axis of the cross.

To the west of Deneb is the brightest star of the summer sky, Vega. Vega belongs to the group called Lyra The Lyre. A lyre is an ancient stringed instrument much like a harp. Vega, just 25 light years away from Earth, is a brilliant, blue-white supergiant star. The other stars of the group form the shape of a slanted box.

To the south of both Deneb and Vega, is Altair, closest of the three stars. Altair is the main star of the constellation Aquila the Eagle and is just 17 light years away. Deneb is the most distant at 1500 light years distance.

Deneb, Vega, and Altair form the famous Summer Triangle. No matter how bright your sky is at night with light from buildings and streetlights, the Summer Triangle is always easily visible. Because of its prominent position overhead, the Triangle will be visible well into the Fall, even though it shifts further to the west each month.

Down on the southern horizon are the stars of Sagittarius. A teapot is the shape most easily seen in the stars of this group. The spout points west, the handle points east and the teapot almost sits flat on the horizon. Because its so far to the south, Sagittarius is only visible for a short time during the summer months. Its companion constellation to the west, Scorpius, prominent in the south early in the summer is already gone by 9 p.m.

The most famous star group, the Big Dipper, is visible all year ‘round. At this time of year, the bowl sits upright just above the northwestern horizon. The handle of the dipper points to the west and the bowl is open to the top of the sky. Just look for seven bright stars low in the northwest, there are no other bright star groups in the area. Enjoy!

Click to get your FREE sky map!

Exploring Our Solar System

Every Month Derrick takes us to another planet in our Solar System - this month we begin with the closest planet to our Sun, the planet Mercury!

Mercury is the planet nearest the sun. It has a diameter of 3,032 miles, about two-fifths of Earth's diameter. Mercury orbits the sun at an average distance of about 36 million miles, compared with about 93 million miles for Earth.

Because of Mercury's size and nearness to the brightly shining sun, the planet is often hard to see from the Earth without a telescope. At certain times of the year, Mercury can be seen low in the western sky just after sunset. At other times, it can be seen low in the eastern sky just before sunrise.

Mercury is the second densest major body in the solar system after Earth and its density is slightly less than the Earths. Mercury's smaller mass makes its force of gravity only about a third as strong as that of the Earth. An object that weighs 100 pounds on the Earth would weigh only about 38 pounds on Mercury.

Mercury has a large iron core which is most likely at least partially molten and generates a magnetic field about 1% as strong as that of Earth's. Mercury's interior appears to resemble that of the Earth. Both planets have a rocky mantle beneath their crust and both planets have an iron core.

Learn More - click MERCURY

Take A Virtual Trip

There is so much to learn about our Solar System. Space.com offers a neat virtual trip to all the planets, comets and more that can be found in our Solar System. Click the Solar System image to the right to take a virtual trip from the comfort of your own home!

Basic Telescope Tips

Choosing a telescope can seem a challenging task for the newcomer to astronomy. There is a bewildering number on the market, with many different names, sizes and decriptions. Essentially, however, they all do the same thing. They act like a large eye to collect lots of light from the distant object being observed and then they magnify it.

There are other instruments that observe different forms of radiation from the universe, such as radio waves, but the observing tools that we are interested in are optical telescopes. Despite the vast choice in the marketplace today, such telescopes come in two basic types - the refractor and the reflector. Variations of the basic forms include hybrids that combine elements from both.

For more information, click the telescope!