Previously,

at Bolides 2009 Prague...

Veres et al. (2009)

Sky-plane probability distribution for impactors 30 days before impact

with V < 22.7 and apparent motion < 12 deg/day

2008 TC3

Sky-plane probability distribution for 3 meterdiameter impactors (bolides) 1 day before impact

with V < 22.7 and apparent motion < 12 deg/day

Veres et al. (2009)

impactor discoveries in a4 year PS1 survey mission

3 night orbit1 night tracklet

Veres et al. (2009)

Veres et al. (2009)

impactor discoveries in a4 year PS1 survey mission

3 night orbit1 night tracklet

So how did CSS find 2008 TC3?

• they got ‘lucky’ or

• there are more small impactors than expected or

• something is wrong with our simulation

ATLAS

STEROID

ERRESTRIALIMPACT

AST

LERT

YSTEM

• John Tonry, PI

• 8 telescopes and cameras– 25cm aperture, f/2.8, 5° FOV, 20 deg2

– 4x4k pixels at 4.4”/pix– 30s exp, 4s readout, 10e- read-noise

• Sensitivity at SNR=5– V=19.3 1 telescope, 1 exp, red & blue– V=20.0 4 telescope, 4 exp, red & blue

• Deployment– 2 pairs x 2 pointings x 2 sites – “blue” (g+r) and “red” (r+i) filters– 2 observations of 20,000 deg2/night

STEROID

ERRESTRIALIMPACT

AST

LERT

YSTEM

ATLAS

A STEROID

ERRESTRIALIMPACT

AST

LERT

YSTEM

TLAS

STEROID

ERRESTRIALIMPACT

AST

LERT

YSTEM

ATLAS

• portable • robotic• autonomous

Ironwood Observatory

STEROID

ERRESTRIALIMPACT

AST

LERT

YSTEM

ATLAS

• Cost• ≈ $2M construction for 2 sites• ≈ $0.5M/year operations• ≈ $1M incremental/site

• Time• 2 years from start of funding

• Asteroid collisions• 10m MB asteroid disruption/day• 100m MB asteroid disruption/year• 1000m dust cloud visible in MB

• Light curves• ~400 photometric observations/year

for ~105 asteroids

• Bolides• One bolide like 2008 TC3 per year

STEROID

ERRESTRIALIMPACT

AST

LERT

YSTEM

ATLAS

ATLAS

ATLASwill identify>60% of allimpactors

STEROID

ERRESTRIALIMPACT

AST

LERT

YSTEM

ATLAS