[Tornadoes, Thunderstorms & Hurricanes] What type of lifting would likely be responsible for the squall line (the narrow band of thunderstorms running northeast to southwest) seen in the following image?  

[Tornadoes, Thunderstorms & Hurricanes] In April, you see this supercell making its way northeast across northern Alabama. Based on the general shape of the supercell, which town is located within the forward-flank downdraft? Click on the correct town on the map.

[Stellar Evolution] A main-sequence star, like our Sun, has a specific life cycle. In the following animation, click on the “Topics” menu and select “Intermediate Mass Stars.” Watch the animation, and then complete the problem that follows. Click here to open the animation in a new window. Place the following events of an intermediate-mass star’s life cycle in chronological order.

[Stellar Evolution] Stars are classified based on their size, temperature, and color. On each of the three scales below, click on the location that characterizes the Sun.

[Stellar Evolution] What force will be responsible for expanding the Sun into a red giant?

[Stellar Evolution] What is the most massive element that can be formed through stellar fusion?

[Planetary Geology] The materials that make up the Earth change as you move from the crust, down through the mantle, and ultimately into the Earth’s core. Select the image of the rock below that you would most likely find in the upper part of the continental crust.

[Stellar Evolution] Whereas spectral classes describe a star’s surface temperature, the absolute magnitude of a star describes the star’s true brightness, or luminosity. The image below shows the same 60-watt lightbulb at various distances from the viewer. Which of the following statements accurately describes the magnitude of the lightbulbs as shown?

[Tornadoes, Thunderstorms & Hurricanes] Buoyant air updrafts often lead to thunderstorm development. Place the following images in the correct order below to show the life cycle of a thunderstorm.      

[Climate Change] Another anthropogenic change the Earth experiences is pollution. Match the type of pollution with the anthropogenic cause.