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 #)
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!
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
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!