Crossword

3. diagram, a diagram that relates the brightness of stars to its surface temperature
4. it is a group of stars
6. X-ray Astrophysics Facility, full form of AXAF
7. It appears to be one of the brightest stars in the Northern Hemisphere
11. these objects are 20,000 times brighter than a star of magnitude of 18
12. telescope, It enables astronomers to study extremely hot objects in space
15. it means "circle of animals" in Greek
16. star patterns that have been discovered but have not been officially identified as a constellation
19. it is the difference in the two solar calendars which is caused by an astronomical phenomenon
20. these are neutron stars flickering with radio pulses

1. it is described in terms of magnitude and luminosity
2. plane, it is the imaginary line traced by the sun in the sky
5. it is a massive ball of plasma held together by its own gravity and emits light
8. it is the measurement of the shift of a nearby object compared to distant objects when observed from two different positions
9. Major, the Big Bear
10. A large cloud of gas and dust
13. It is one of the most prominent star patterns in the sky
14. one myth claims that it is always visible in the Northern Hemisphere but not in the Southern Hemisphere
17. it occurs when star more massive than our sun run out of fuel
18. It refers to an opaque object that emits thermal radiation