1. 天导小组讨论 计科 20 赵锦煦

2. p21.56 apod.nasa.gov/apod  APOD: Astronomy Picture of the Day  April 22, 2016: The Bubble Nebula  APOD: Astronomy Picture of the Day  April 22, 2016: The Bubble Nebula

3. The Bubble Nebula

4.  Was the image or video taken from Earth or from space ?  Is it a combination of several images?  Yes. A combination of 3 pictures with different filters.  Does it show Earth, our Solar System, objects in our Milky Way Galaxy, more distant galaxies, or something else?  7,100 light-years, constellation Cassiopeia （仙后座）  Was the image or video taken from Earth or from space ?  Is it a combination of several images?  Yes. A combination of 3 pictures with different filters.  Does it show Earth, our Solar System, objects in our Milky Way Galaxy, more distant galaxies, or something else?  7,100 light-years, constellation Cassiopeia （仙后座）

5. The Bubble Nebula  Is the explanation understandable to someone who has not studied astronomy?  Do you think this website promotes a general interest in astronomy?  Is the explanation understandable to someone who has not studied astronomy?  Do you think this website promotes a general interest in astronomy?

6. The Bubble Nebula

7.  7 light-year diameter  Above and left of the Bubble's center is a hot, O-type star, several hundred thousand times more luminous and around 45 times more massive than the Sun.  A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud.  7 light-year diameter  Above and left of the Bubble's center is a hot, O-type star, several hundred thousand times more luminous and around 45 times more massive than the Sun.  A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud.

8. The WFC3  The Wide Field Camera 3 (WFC3) is the Hubble Space Telescope's last and most technologically advanced instrument to take images in the visible spectrum.  It was installed as a replacement for the Wide Field and Planetary Camera 2 during the first spacewalk of Space Shuttle mission STS-125 on May 14, 2009.  Replacement to WFC2: degradation of the CCDs, resulting in defective ("hot") pixels.  The Wide Field Camera 3 (WFC3) is the Hubble Space Telescope's last and most technologically advanced instrument to take images in the visible spectrum.  It was installed as a replacement for the Wide Field and Planetary Camera 2 during the first spacewalk of Space Shuttle mission STS-125 on May 14, 2009.  Replacement to WFC2: degradation of the CCDs, resulting in defective ("hot") pixels.