Introductory Astrononomy - Lesson #1

[cinnabun1322]

Andrew stared at the galaxy in awe and raised his hand to answer the question, "A lightyear is a unit of length, equal to just under ten trillion kilometers. It measures the distance that light travels in a vacuum in a Julian year."

[Kaiia Blackthorn]

"An excellent definition - two points to Gryffindor. The distance to this galaxy means that the light from it takes 27 million years to reach us. As a comparison, light from our sun takes eight minutes to reach us. We see the galaxy as it looked 27 million years ago." Kaiia paused, watching the galaxy slowly revolve. "Can anyone name some other spiral galaxies?"

[cinnabun1322]

Andrew grinned as his answer was right and raised his hand again, "There is the Triangulum, the Whirlpool, the Sunflower, Andromeda, and our own Milky Way Galaxy." He looked at Bella with a slight smirk.

[isabellapeters]

"Well two other galaxies in Ursa Major are Bode's Galaxy and Cigar Galaxy," Isabella said rasing her hand. She glanced at Andrew and smiled, he'd managed to get some points for his house.

[Kaiia Blackthorn]

"Very good. Two points each. The Cigar galaxy was once thought to be an irregular galaxy, but is actually a spiral galaxy seen edge-on. It's not easy to see that it's a spiral."


"However NGC 4565 is a better example of an edge-on spiral, as you can see the flattened disk, with a central bulge where the stars are more densely concentrated."


"The Whirlpool galaxy is an excellent example of a face-on spiral, but it's also interesting because it has a companion galaxy known as NGC 5195, and the two galaxies are quite clearly interacting. You can see where dust is being drawn from the smaller galaxy into the larger one. This interaction is responsible for the Whirlpool having such clearly-defined spiral arms."


"Can someone name any other galaxy types besides spirals?"

[cinnabun1322]

Andrew raised his hand. So studying really does pay off. Now I understand what Bella is always trying to tell me. "There are elliptical galaxies and irregular galaxies, professor."

[Kaiia Blackthorn]

"Can you give me an example of each?" It looked as if at least some of the students had not only done the required reading, but looked a little further.

[isabellapeters]

Bella smiled to herself as Andrew answered a question, maybe pestering him has finally worked. She raised her hand and said, "The closest giant ecliptical galaxy is called Maffei 1. An example of an irregular galaxy is the Pegasus Dwarf Irregular Galaxy."

[Kaiia Blackthorn]

Kaiia was impressed. She nodded, looking at Isabella with interest. "Yes, Maffei 1 is an excellent example. It can be seen in the constellation Cassiopeia, and as you say, it's the closest giant elliptical galaxy."



"If it wasn't obscured by dust and stars from our galaxy, it would be very bright, and certainly better known. As it is, relatively few people have heard of it. May I ask if you have an interest in astronomy beyond what you are required to learn for school?"

[isabellapeters]

Isabella was quiet for a moment, she liked astronomy that much was true. What she didn't know was exactly what 'interests beyond the curriculum' meant. "I guess so professor," she said eventually with a small smile. "I like learning about stars and space and stuff."

[Kaiia Blackthorn]

Kaiia saw the girl's baffled look, and said, "What I mean is, do you do any reading on astronomy, or observing, that's not related to what you're learning in class? For fun, in other words."

[isabellapeters]

Bella smiled, if the Professor had worded it that way she would've been able to answer straight away. "Well I like lying under the stars at night trying to spot the different constallations," she said trying not to blush. She knew Sam was right behind her and with Andrew next to her judging her it was becoming really hard to say her hobbies.

[cinnabun1322]

Andrew set his elbow on his desk and looked Bella with a grin as he looked at Bella playfully. He smirked as he heard a new side of his best friend and listened for her to finish still looking at her.

[JadieLou]

Sam sat behind Bella, looking at her back, looking her up and down. He smiled when she answered. She sounded so awkward, like she was embarrased by her hobbies. He smiled and looked over at Andrew, who was looking at her as intently as he was. He scowled at him. Stay away from my girl, you prick, he thought.

[Kaiia Blackthorn]

Jul 29, 2008 23:38:52 GMT 8 @isabellapeters said:

Bella smiled, if the Professor had worded it that way she would've been able to answer straight away. "Well I like lying under the stars at night trying to spot the different constallations," she said trying not to blush. She knew Sam was right behind her and with Andrew next to her judging her it was becoming really hard to say her hobbies.

Seeing Isabella's expression, Kaiia almost forgot herself and smiled. She'd picked up the habit of using convoluted sentences from Damon, who'd never used one word where ten would do just as well. She nodded at her description of star gazing. "Yes - I've done the same myself. It's very peaceful."

Jul 30, 2008 1:14:57 GMT 8 JadieLou said:

Sam sat behind Bella, looking at her back, looking her up and down. He smiled when she answered. She sounded so awkward, like she was embarrased by her hobbies. He smiled and looked over at Andrew, who was looking at her as intently as he was. He scowled at him. Stay away from my girl, you prick, he thought.

Kaiia caught the look that Sam gave Andrew. A rivalry? This could liven up astronomy lessons, she thought with relish. It would be interesting to see how it unfolded.

"Does anyone have any questions?" she asked aloud. "About what we'll be studying this term, or anything astronomy-related? Does anyone have a particular interest they'd like me to focus on?"