Workshop at the MSSL Work Experience Week 2015 on Gaia

1. GEORGE SEABROKE
Mapping the Milky
Way from space
MULLARD SPACE SCIENCE LABORATORY
Credits: ESA/ATG
medialab;
background image:
ESO/S. Brunier

3. MULLARD SPACE SCIENCE LABORATORY

6. 6
Milky Way (artist’s impression):
How many stars?
Credit: NASA/JPL-Caltech/R. Hurt

7. 7
Milky Way (artist’s impression):
100-200 billion stars
Credit: NASA/JPL-Caltech/R. Hurt

8. 8
Gaia will measure astrometry & photometry of ? stars
& radial velocities of ? stars
Credit: NASA/JPL-Caltech/R. Hurt

9. 9
Gaia will measure astrometry & photometry of 1
billion stars & radial velocities of 75-100 million stars
Credit: NASA/JPL-Caltech/R. Hurt
Distribution of stars
for which radial
velocities will be
precisely
(< 15 km/s)
measured
(V < 15.2)
in a mock spiral
galaxy as seen by
Gaia, as predicted
by SNAPDRAGONS
(Hunt et al. 2015)
Log (star #)

11. MULLARD SPACE SCIENCE LABORATORY
Credit: Leanne Guy

13. One of the primary mirrors being mounted on Gaia
13

14. Credit:
Astrium SAS

15. Gaia’s 106 CCDs integrated onto its focal plane

16. Gaia’s 106 CCDs integrated onto its focal plane
Credit: Astrium
 106 digital cameras, each with 8.8 Mega pixels
 106 x 8,847,000 pixels = 937,782,000 pixels
 Nearly 1 billion pixels or 1000 Mega pixels!

20. 0.5°

21. Gaia
0.000000002°
0.000000002°

22. Spectroscopy
Redder
colours:
longer
wavelengths
Bluer colours:
shorter
wavelengths

23. Electromagnetic spectrum
Victor Blacus (http://en.wikipedia.org/wiki/File:Electromagnetic-Spectrum.svg)

24. Victor Blacus (http://en.wikipedia.org/wiki/File:Electromagnetic-Spectrum.svg)
Electromagnetic spectrum

26. Doppler effect with sound waves

27. Doppler effect with sound waves

28. Doppler effect with light waves
http://www.astronomynotes.com/light/s10.htm

29. What is a radial velocity?

30. What is a radial velocity?
Position

31. DDistance measured by parallax
What is a radial velocity?
Position

32. DDistance measured by parallax
What is a radial velocity?
Position

33. DDistance measured by parallax
Distance
converts
proper motions
to
transverse velocity (Vt)
What is a radial velocity?
Position

35. Effect of parallax
(the Earth’s orbital
motion around the
Sun, with a period
of 1 year).

36. System’s
barycentric
motion viewed
from the Solar
System barycentre.

37. Exo-Planets
System’s
barycentric
motion viewed
from the Solar
System barycentre.
Effect of parallax
(the Earth’s orbital
motion around the
Sun, with a period
of 1 year).
Apparent motion of the
star as a result of the
planet, the
additional perturbation
being magnified by
×30 for visibility.

38. DDistance measured by parallax
Distance
converts
proper motions
to
transverse velocity (Vt)
Space velocity
(any direction)
What is a radial velocity?
Position

39. DDistance measured by parallax
Distance
converts
proper motions
to
transverse velocity (Vt)
Space velocity
(any direction)
Radial velocity (Vr)
What is a radial velocity?
Position
http://www.projectrho.com/public_html/starmaps/media/4dmaps/spacevel.png

40. Modelling the Milky Way using supercomputers
Rob Grand, Jason Hunt (PhD students), Daisuke Kawata, MSSL

41. http://en.wikipedia.org/wiki/Oort_cloud

42. Gaia’s first science result: supernova!

43. Gaia’s first science result: supernova!

45. • hosts more than 10 billion photos

46. • hosts more than 10 billion photos
• 1 petabytes (PB) = 1 million gigabytes (GB)

47. • hosts more than 10 billion photos
• 1 petabytes (PB) = 1 million gigabytes (GB)
• Gaia’s final processed data storage = several PB

48. Summary
• Great recent years for the European Space Agency!
• 3 take home messages about Gaia:
–Amazing (European) technology
–Stars move!
–You can get involved!