Your SlideShare is downloading. ×
0
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Mission Critical Risk Taking: The Hubble Deep Field by Robert Williams

71

Published on

MivaCon 2014: Mission Critical Risk Taking: The Hubble Deep Field …

MivaCon 2014: Mission Critical Risk Taking: The Hubble Deep Field

Presented by Robert Williams, Space Telescope Inst., Johns Hopkins University

Published in: Business
0 Comments
0 Likes
Statistics
Notes
  • Be the first to comment

  • Be the first to like this

No Downloads
Views
Total Views
71
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
Downloads
1
Comments
0
Likes
0
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Mission Critical Risk-Taking: The Hubble Deep Field Robert Williams Space Telescope Inst/Johns Hopkins U.
  • 2. GlobForeA)SM1   Kapteyn  1922   Hubble  1929   Kepler  1596   Concepts of the Universe Digges  1576  
  • 3. Kravtsov & Wechsler 2010, U. Chicago
  • 4. .        .                          .   Springel 2013 Max-Planck-Institut
  • 5. HSTLaunch   April  1990  
  • 6. HSTSchema8c   Mirror:  2.4m  diameter   Mass:    11,000    Kg   Length:    13  meters   Development  Cost:    $2.5    billion   Opera8ons  24  yrs:    $5.5  billion  
  • 7. HST  over  Earth  
  • 8. R136Blurred  
  • 9. CartoonFirstPics  
  • 10. CartoonFirstPics  
  • 11. Cartoon2  
  • 12. OTA  Components  
  • 13. WFPC2Tank  
  • 14. GlobForeA)SM1  
  • 15. What the Longest Exposures from the Hubble Space Telescope Will Reveal JOHN N. BAHCALL, PURAGRA GUHATHAiKURTA,DONALD P. SCHNEIDER Detailed simulations are presented of the longest expo- sures on representative fields that will be obtained with the Hubble Space Telescope, as well as predictions for the numbers and types of objects that will be recorded with exposures of different durations. The Hubble Space Tele- scope will reveal the shapes, sizes, and content of faint, distant galaxies and could discover a new population of Galactic stars. T HE HUBBLESPACETELESCOPE(HST) IS SCHEDULEDTO be launchedsoon andthefirstscientificobservationsshould be availablewithin severalmonths. Many authorshave discussedthe qualitativeadvancesthatmaybe anticipatedwith an orbitingspacetelescopeinsuchdiverseareasasastrometry,interstel- larmatter,stellarevolution,galacticstructureandevolution,quasar research,andcosmology(1,2). Formostobservations,theHSTwill be pointedat individualobjectsor fieldsof specialinterest.We discussthe specificset of observationsin whichthe telescopewill takepicturesof randomfields(devoidof objectsknowna priorito beof specialinterest)inorderto determinethestatisticalcharacteris- ticsof faintgalaxiesandstars. In this articlewe presentquantitativepredictionsof what the HST imagesof these representativefieldswill show basedupon whatwe knowfromground-basedtelescopes.The comparisonof the HST observationswith these predictionswill constitutean objectivemeasureof what HST discoversaboutthe propertiesof faintgalaxiesand stars.Our workinghypothesis,which will be testedbyHSTobservations,isthateverythingin theHST universe haspreviouslybeenrevealedby ground-basedobservations.Using V = 19.5 (near-infraredmagnitude I - 18.5); there are approxi- mately0.1 stars(or galaxies) arcmin-2 mag- I at this magnitude. By V = 22.5, the galaxies outnumber the stars by a factor of 10, and there are about 2.5 galaxies arc min-2 mag'l. At V = 25, the expected number of stars (-0.35 arc min-2 mag-1) is only 1% of the number of galaxies. The limiting flux level reached by long exposures on stars or faint, distant galaxies scales approximately proportional to the inverse square root of the observing time. We do not expect HST to reveal a new population of galaxies. Ground-basedobservations can detect galaxiesto avisualmagnitude limit of about V = 27 (3). This is also the approximate detection limit for relativelycompact objects (radius -0".2) with HST in the longest plannedexposures by guaranteedtime observers(GTOs) (4, 5). For a given luminosity, the more compact the object the easierit is to detect. To escape detection from the ground but still be observed with HST, the faintest galaxies (V > 27) must have angular radii of less than -0".2; this seems an unlikely possibility (see our discussion below of Fig. 4). In agreementwith previous authors,our analysissuggests that the major contribution of HST for galaxy researchwill be in revealing the shapes, sizes, and content of previously unresolved galaxies. Table1. Thenumberdensityof faintgalaxiesandstars.Thecalculatedtotal numberofobjectspersquarearcminuteathighGalacticlatitudeswithvisual magnitudes,V, and near-infraredmagnitudes,I, less than the specified brightness,m.Alsoshownarethecalculatednumberof starspersquarearc minute. For specificity,the luminosityfunctionsof faint spheroidand disk starsare assumedconstantbetweenMv = 12 and Mv = 16.5 No browndwarfsareincluded.The V galaxycountsareassumedto followa powerlawbeyondV = 26, andtheI countsareVmagnitude-limitedwith Vmax= 28 and30 for galaxiesandstars,respectively.The numbersgiven herereferto the inputdatato thesimulationsandnot to thenumbersthat wouldbe detected,whichdependuponexposuretime,detectorefficiency, Bahcall  et  al.  
  • 16. 3C324 Distance=8 Billion light yrs
  • 17. Nearby Galaxies Nearby Galaxies (Present epoch) Distant Galaxies (8 Byr ago)
  • 18. HDF Spiral Galaxy NGC 3370
  • 19. HDF
  • 20. Palomar Hubble Telescope Hubble Deep Field ?
  • 21. Palomar Hubble Telescope Hubble Deep Field 10″ Hubble Deep Field − North HST • WFPC2 December 1995
  • 22. HDF 10″ Hubble Deep Field − North HST • WFPC2 December 1995
  • 23. from   Hubble  Deep  Field  
  • 24. WFPC2Dark  
  • 25. HUDF   Black Hole Stars Orbiting Center of the Milky Way Galaxy
  • 26. UniverseHistory  
  • 27. HDF 10″ Hubble Deep Field − North HST • WFPC2 December 1995
  • 28. History  of  Universe   History  of  the  Universe  
  • 29. StoreyonArm  
  • 30. HDF

×