Astrometric Surveys in the Astrometric Surveys in the Next DecadeNext Decade

Dave MonetDave Monet

U.S. Naval Observatory Flagstaff StationU.S. Naval Observatory Flagstaff Station

June 15, 2011June 15, 2011

PresumptionsPresumptions

• Currently operational:Currently operational: Pan-STARRS – 100,000 exposures taken so far.Pan-STARRS – 100,000 exposures taken so far. SkyMapper – operational after fix of telescope shake issues.SkyMapper – operational after fix of telescope shake issues. Kepler – Kepler – Q8Q8 on ground.on ground. UKIDSS, etc.UKIDSS, etc.

• Will happen:Will happen: GaiaGaia – Current launch date is May 2013 – see poster. – Current launch date is May 2013 – see poster. J-MAPS – Current launch date is July 2014.J-MAPS – Current launch date is July 2014. LSST – PDR in Aug 2011, inclusion in FY14 Federal budget?LSST – PDR in Aug 2011, inclusion in FY14 Federal budget?

• No change in resource limitations (NSF, NASA, etc).No change in resource limitations (NSF, NASA, etc). No more Congressional earmarks.No more Congressional earmarks.

Relevant EquationsRelevant Equations

• Accuracy = FWHM / SNRAccuracy = FWHM / SNR Limited by seeing on the ground – F(exposure time, site, etc.).Limited by seeing on the ground – F(exposure time, site, etc.). Limited by ? in space – TBD from Limited by ? in space – TBD from Gaia, KeplerGaia, Kepler, etc., etc.

• Velocity = 5 × motion × distanceVelocity = 5 × motion × distance km/sec, arcsec/year, parsec.km/sec, arcsec/year, parsec. km/sec, mas/year, kpc.km/sec, mas/year, kpc.

• Parallax = 1 / distanceParallax = 1 / distance arcsec, parsec.arcsec, parsec. mas, kpc.mas, kpc.

Quick Summary of Quick Summary of GaiaGaia

• GaiaGaia will work as advertised: will work as advertised: http://www.star.le.ac.uk/great_workshop/talks/Jordan_talk.pdfhttp://www.star.le.ac.uk/great_workshop/talks/Jordan_talk.pdf 1e9 stars with amazingly good astrometry + photometry.1e9 stars with amazingly good astrometry + photometry.

• GaiaGaia catalog will be the 600-lb gorilla in the room: catalog will be the 600-lb gorilla in the room: Guess: G2020 will replace J2000.Guess: G2020 will replace J2000. Guess: gu, gg, gr, gi, gz bands will replace SDSS as reference.Guess: gu, gg, gr, gi, gz bands will replace SDSS as reference. Guess: Intermediate catalog (mas; 2015?) changes everything.Guess: Intermediate catalog (mas; 2015?) changes everything.

• Will put USNO astrometry+catalogs out of business.Will put USNO astrometry+catalogs out of business. Guess: Final catalog will be last astrometry catalog for decades.Guess: Final catalog will be last astrometry catalog for decades.

• For those of us who are not part of For those of us who are not part of GaiaGaia:: How do we How do we GaiaGaia-proof our products?-proof our products? How do we How do we GaiaGaia-proof our careers?-proof our careers?

• Resistance (to Resistance (to GaiaGaia) is futile!) is futile!

Quick Summary of LSSTQuick Summary of LSST

• LSST astrometry is almost LSST astrometry is almost GaiaGaia-proof:-proof: Cross-over magnitude where LSST becomes more accurate.Cross-over magnitude where LSST becomes more accurate.

• GaiaGaia runs out of photons and bandwidth. runs out of photons and bandwidth.

• Guess: about 19Guess: about 19thth depending on CR damage to Gaia CCDs. depending on CR damage to Gaia CCDs.

• Bright stars will give rigid tie between LSST and Bright stars will give rigid tie between LSST and GaiaGaia..

• Faint stars (down to 26Faint stars (down to 26thth and beyond) will deliver the new science. and beyond) will deliver the new science. Cross-over crowding:Cross-over crowding:

• GaiaGaia has 2 fields of regard in same focal plane. has 2 fields of regard in same focal plane.

• At some star density, confusion will degrade accuracy.At some star density, confusion will degrade accuracy.

• LSST has bigger images but a single field of regard.LSST has bigger images but a single field of regard.

• LSST can do difference imaging and analysis.LSST can do difference imaging and analysis. LSST is not all-sky.LSST is not all-sky.

• Did somebody mention “resources”?Did somebody mention “resources”?

• Can we learn “enough” from PS?Can we learn “enough” from PS?

Impact - 1Impact - 1

• Pan-STARRS PS1 and SkyMapper need to hurry!Pan-STARRS PS1 and SkyMapper need to hurry! Huge amount of astrometry to be done:Huge amount of astrometry to be done:

• My poster child is finding star that killed dinosaurs.My poster child is finding star that killed dinosaurs.

• Parallax of every star in sky.Parallax of every star in sky.

• Survey of proper motions from large to small.Survey of proper motions from large to small.

• Learn large database astrometry by doing it.Learn large database astrometry by doing it.

• Learn how to do crowded field astrometry.Learn how to do crowded field astrometry.

• Amazing opportunities in -30≤δ≤0 overlap zone.Amazing opportunities in -30≤δ≤0 overlap zone. Huge impact on most other astronomical disciplines.Huge impact on most other astronomical disciplines. But – Game Over! when But – Game Over! when GaiaGaia publishes Intermediate catalog. publishes Intermediate catalog.

• Anticipate mas astrometry, mmag photometry over all sky.Anticipate mas astrometry, mmag photometry over all sky.

• Guess: Release is politically and scientifically important.Guess: Release is politically and scientifically important.

• Guess: As early as is reasonable – 2015 or 2016.Guess: As early as is reasonable – 2015 or 2016.

Impact - 2Impact - 2

• No need for all-sky (RA,Dec) block adjustment solution.No need for all-sky (RA,Dec) block adjustment solution. What is science driver between now and first What is science driver between now and first GaiaGaia release? release?

• Only one I know is solar system orbits – fixed USNO-B seems OK.Only one I know is solar system orbits – fixed USNO-B seems OK. Gaia Gaia Intermediate catalog will blow all of this away.Intermediate catalog will blow all of this away.

• Concentrate on really cool new results:Concentrate on really cool new results: We don’t need μas astrometry for stars within 100pc.We don’t need μas astrometry for stars within 100pc.

• Parallax solutions possible after first year of survey.Parallax solutions possible after first year of survey.

• PS1 is ready to rock ‘n roll! SkyMapper is almost ready to go!PS1 is ready to rock ‘n roll! SkyMapper is almost ready to go! Is there a population of fast/red/faint stars that Luyten missed?Is there a population of fast/red/faint stars that Luyten missed?

• 50 mas/year should be like shooting fish in a barrel.50 mas/year should be like shooting fish in a barrel. Galactic plane is pretty much unsurveyed – can we do it now?Galactic plane is pretty much unsurveyed – can we do it now?

• Learn how to do differential image astrometry.Learn how to do differential image astrometry.

• Work on Work on GaiaGaia-proof (faint, really red, crowded) topics.-proof (faint, really red, crowded) topics.

PS1 Status in May 2011 – 77,619 3π exposures

Don’t Forget About Don’t Forget About KeplerKepler

• AΩ (etendue) is about 100.AΩ (etendue) is about 100. Larger than anything other than LSST.Larger than anything other than LSST.

• Example of cadence optimized for time not space.Example of cadence optimized for time not space. Same sky every 15 minutes for 3.5 (or more) years.Same sky every 15 minutes for 3.5 (or more) years.

• Experiment optimized for high SNR:Experiment optimized for high SNR: CDPP is 20 parts per million (= 20 μmag) every 6 hours.CDPP is 20 parts per million (= 20 μmag) every 6 hours. Astrometry well beyond 0.001 pixel.Astrometry well beyond 0.001 pixel.

• Really cool astrophysics:Really cool astrophysics: So much more than finding planets.So much more than finding planets. Asteroseismology – study cores of stars in detail.Asteroseismology – study cores of stars in detail. Variable stars, eclipsing binary, planetary weather, etc.Variable stars, eclipsing binary, planetary weather, etc. Q0 and Q1 public now, Q2 (maybe more) in September 2011.Q0 and Q1 public now, Q2 (maybe more) in September 2011.

Residuals after Affine transformationResiduals after Affine transformation

Sample of 11 known giants on Channel 50 in Q5

-0.0

1

Pix

el

+0.

01

Conclusions - 1Conclusions - 1

• Given astrometry, how to follow up neat stuff?Given astrometry, how to follow up neat stuff? Example – Example – KeplerKepler has totally saturated RV assets. has totally saturated RV assets. How can we possibly follow up PS1, SkyMapper, How can we possibly follow up PS1, SkyMapper, GaiaGaia, LSST?, LSST?

• Prepare for success, not failure.Prepare for success, not failure.

• Data fusion?Data fusion? Astrometry is just an enabling technique.Astrometry is just an enabling technique. Practice on PS and SkyMapper before deluge from Practice on PS and SkyMapper before deluge from Gaia,Gaia, LSST. LSST. Real opportunities in -30≤δ≤0 PS1+SM overlap zone.Real opportunities in -30≤δ≤0 PS1+SM overlap zone.

• How do we do V&V on 1e10 objects?How do we do V&V on 1e10 objects? Our colleagues might actually believe values in the database.Our colleagues might actually believe values in the database.

• Cadence is everything!Cadence is everything! The The Cadence WarsCadence Wars are coming. are coming. Each science collaboration needs to be prepared.Each science collaboration needs to be prepared.

Conclusions - 2Conclusions - 2

• Current ground-based optical astrometry programs are toast.Current ground-based optical astrometry programs are toast. Throw us to the sharks to please managers?Throw us to the sharks to please managers?

• ““Turn things OFF!” is their mantra.Turn things OFF!” is their mantra. Close facilities like USNO? (or maybe !)Close facilities like USNO? (or maybe !) Fire astrometrists as being obsolete.Fire astrometrists as being obsolete. Game over!Game over!

• New imaging surveys should have astrometric “self follow up”.New imaging surveys should have astrometric “self follow up”. You put us out of business.You put us out of business. No other facilities that can do this.No other facilities that can do this. Even if you are targeting galaxies or gravity, stars get in the way.Even if you are targeting galaxies or gravity, stars get in the way.

• Astrometry is nothing more than FWHM/SNR.Astrometry is nothing more than FWHM/SNR.

• Please think about it as part of the survey strategy.Please think about it as part of the survey strategy.