This week in the News: April 27, 2008
On Wednesday, April 23, 2008, researchers say they saw a supermassive black hole belch into the cosmos. This was no ordinary "burp," however. This belch released a jet of supercharged particles. Astronomers knew black holes did this, but this was the first time they actually witnessed how these jet streams are formed. Winding the particles like a corkscrew, black holes spew them out close to light speed.
As space science improves, so does what we know about the cosmos. One thing astronomers have learned is that large black holes form the core of numerous galaxies and exert powerful gravitational forces. Also, black holes and galaxies are constantly moving matter and energy.
Hold onto your seat for this week's lesson, as you explore gravity's key role in galaxy collisions the powerful force of black holes.
The Crashing Cosmos
What happens when galaxies crash together? To see the big picture, visit HubbleSite's Cosmic Collision page. Start with the overview on Striking Encounters, near the bottom of the page. Make sure to have your speakers or headphones on.
What does gravity have to do with why collisions happen? About how long does a collision last, from start to finish?
Next, watch Cosmic Collision: The End of the Milky Way. This movie tells you more about our own galaxy and the impending crash with Andromeda. After the introduction, click to continue to the Galaxy Evolution segment. At the end of the segment, click to explore more about The Expanding Universe before moving on to the next segment. What do scientists believe is accelerating the expansion of the universe? How will that affect the probability of two galaxies crashing together as time goes on?
Continue with the main show to watch the next part explaining Collision Dynamics. What happens to existing stars, gas, and dust, when two galaxies collide? When done with that segment, review Gravity: The Ties That Bind. What variable drives the strength of gravity? Also, explore the nature of Dark Matter. Why do scientists believe that dark matter exists, even though it has never been "seen"? Why does it affect galaxy collisions?
Click to continue the show, but before moving on to the final segment, explore more with Shaping Up: Galaxies After Collision. What are the two key variables that determine the shape of the outcome?
Lastly, watch the Fate of the Milky Way segment. As you will discover, Andromeda is heading straight for us. This will not be the first time our galaxy has collided with another, however. Explore more to reveal Current Milky Way Collisions.
Into the Black Hole
Start by dragging around the viewfinder to locate all of the objects on the Your Findings list to the right of the image. Click one of the satellite types—x-ray, visible light, or radio waves—to view through that particular viewfinder. When you locate a black hole, click to learn more. Just under the image on the detail page, click previous or next to view the black hole through the other telescope filters. Click close to return to the main image, and continue your task until you have found all of the black holes on the list.
When your list is complete, Begin Your Voyage. Choose your destination of either Cygnus X-1 or Andromeda. Follow the screen instructions to complete your journey. What cosmic objects do you see along the way? Once you have reached your destination and identified its parts, click for an Up Close and Personal view of orbiting a black hole. Click to learn more, and read the more detailed explanation.
On the left-hand side of that detail screen, click to try the experiments listed. You can orbit a black hole, find the mass of a black hole, drop a clock into a black hole, fall into a black hole, and even create a black hole. As you complete the experiments, explore the related questions.
Compare what you know about planets and what you have learned about black holes. Create two lists—one for planets and one for black holes—which describe general characteristics of each type of object. Think about questions such as, how are lightwaves affected when they interact with the object? What variables influence the strength of gravity? Where is the object located relative to other cosmic objects? Discuss your lists with classmates.
Browse issues Sacramento Bee, looking for any articles related to research in astronomy fields. Choose one of the article topics to dig deeper into that topic. Write a short paper that describes how that topic relates to what you learned in this lesson. What role does gravity play? How does the news relate to a particular galaxy? What physics concepts are at work? Develop diagrams to illustrate your findings.
Weekly News Topics
Each week The Bee publishes a new weekly news topic for students who use the Internet and newspaper as learning resources. The weekly news topic are tied to current events in the news and help students extend their knowledge on a wide range of subjects. Click here to return to the table of contents.
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