Imaging Science Fundamentals Chester F. Carlson Center for Imaging Science

The LASP* at RIT’s The LASP* at RIT’s Center for Imaging ScienceCenter for Imaging Science

*Laboratory for Astronomy in Strange Places

Telescopes on Mauna KeaTelescopes on Mauna Kea

Altitude circa 14,000 ft.

The Kuiper Airborne ObservatoryThe Kuiper Airborne Observatory

Altitudes up to 45,000 ft.

Higher is Better: Roots of the LASPHigher is Better: Roots of the LASP

CIS’s Director (as grad student!) in action on the Kuiper Airborne Observatory(1970-something)

Why is higher better?Why is higher better?

Why Do Astronomy in the Infrared?Why Do Astronomy in the Infrared?

Most of the luminosity of our galaxy and in other galaxies emerges in this wavelength region

Low dust extinction at these wavelengths permits unbiased and potentially complete observations of statistically large samples of objects

Formation of galaxies in the early universe and the crucial stages of formation and evolution of stars and planets can be best studied in this range of wavelengths

Most of the fundamental absorption and emission lines and bands of astrophysically and astrochemically significant molecules occur in the far infrared

M17: Optical Photograph + Far InfraredM17: Optical Photograph + Far Infrared

That was then...That was then...

Kuiper AirborneObservatory mapsof far-IR emissionfrom the W3 star formation region,1970-something

This is now...This is now...

The W3 starformationregion as seenin the near-IRby a modernIR camera

Youngest stars in M17 hidden by dustYoungest stars in M17 hidden by dust

Near-Infrared Imaging:Near-Infrared Imaging:Uncovering the young stars in M17Uncovering the young stars in M17

Constructing a Spatial MosaicConstructing a Spatial Mosaic

Mosaics obtained at Mosaics obtained at three infrared wavelengthsthree infrared wavelengths

2.2 microns 1.65 microns 1.25 microns

Result of combining...Result of combining...

Visible InfraredVisible Infrared

Big targets need big detector arraysBig targets need big detector arrays

The galactic center region in the near-IR

This image took a long time to make...This image took a long time to make...

…because this imageof M17 (fromlate 1980’s)consists of amosaic of several dozenindividual58x62 frames

But this one was a snap!But this one was a snap!

Image of M17taken inmid-1990’swith a 256x256 near-infrareddetector array

The advantages of colorThe advantages of color

Using a bigger telescope to see detailUsing a bigger telescope to see detail

Image Processing: Image Processing: Separating Stars from NebulaSeparating Stars from Nebula

Narrow-band IR imaging:Narrow-band IR imaging:Distinguishing the dust from the gasDistinguishing the dust from the gas

Dust emission from M17at 3.3microns

Emission from ionized gas at 2.16 microns and 4.05 microns

Colder is also betterColder is also better

Why is colder better?Why is colder better?

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Sky brightness and Ambient Temperature

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Sky Brightness

Ambient Temperature

Sky gets darker as temperature dropsSky gets darker as temperature drops

Construction at the PoleConstruction at the Pole

The SPIREX TelescopeThe SPIREX Telescope

The SPIREX TelescopeThe SPIREX Telescope

Data Pipelining at RITData Pipelining at RIT

Data from the South Pole National request for proposals 45 proposals received; 13 carried

out Data reduced at RIT and

distributed worldwide

The Galactic Center viewed from the PoleThe Galactic Center viewed from the Pole

Star formation regions from the PoleStar formation regions from the Pole

The advantage of infrared imaging from a cold environment

Star formation regions from the PoleStar formation regions from the Pole

The advantage of infrared imaging with a wide field

A A veryvery wide field 3-color IR image wide field 3-color IR image

Image mosaic of the NGC 6334 star formation region obtained with SPIREX/Abu at the South Pole

Site monitoring for the entire seasonSite monitoring for the entire season

The advantage of relentless observing & data pipelining

How to tell when it’s cloudyHow to tell when it’s cloudy

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Trying to Observe When Partly Cloudy

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How to tell the good times from the badHow to tell the good times from the bad

HR 3842: L counts vs. background

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How to squeeze blood from a rockHow to squeeze blood from a rock(Or, how to make the bad times look like the good)(Or, how to make the bad times look like the good)

HR 3842: L counts vs. background

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3.00E+053/31/99 0:00

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The SOFIA ConceptThe SOFIA Concept

Test flightsTest flights

Telescope specificationsTelescope specifications

Nominal Operational Wavelength Range: 0.3 to 1600 um prime wavelengths 15-300 microns

Primary Mirror Diameter = 2.7 meters System Clear Aperture Diameter = 2.5 meters Nominal System f-ratio = 19.6 Primary Mirror f-ratio = 1.28 Telescope's Unvignetted Elevation Range: 20-60

degrees

The mirror blankThe mirror blank

SOFIA Key ScienceSOFIA Key Science

Interstellar cloud physics and star formation in our galaxy

Proto-planetary disks and planet formation in nearby star systems

Origin and evolution of biogenic atoms, molecules, and solids

Composition and structure of planetary atmospheres and rings, and comets

Star formation, dynamics, and chemical content of other galaxies

The dynamic activity in the center of the Milky Way.

SOFIA Data Pipelining at RITSOFIA Data Pipelining at RIT

Under construction: a data cycle system for SOFIA

Our data cycle system will be modular, extensible, and continuously improving

These 3 attributes are the promise of SOFIA

In the works: telescopes on the In the works: telescopes on the Atacama Plateau, ChileAtacama Plateau, Chile

Talk about astronomy in strange places…!

• Altitude: circa 19000 ft.• Rainfall: almost never