The Advanced Technology Solar Telescope

The ATST Project is funded by the National Science Foundation through the National Solar Observatory which is operated by the Association of Universities for Research in

Astronomy (AURA), Inc.

The Site & Buildings for ATST

• Where on Haleakalā would ATST be?

• How big would the facility be?

• What would it look like?

• Why does it look like that?

For Jeff Barr - Project ArchitectMarch 2006

Overall Site Plan

PrimaryMeesSite

Archaeologicalfeatures

Property lines

Air ForceFacilities

petrel burrowsAhu

ElectricSubstation

SecondaryReber CircleSite

Primary Proposed (Mees) Site

Mees

Alternate Site(Reber Circle)

Both described as potential ATST sites in HO Long Range Development Plan.

Big enough for ATST without major earth moving or civil work.

Local observing conditions proven good by site testing.

Current Views of Sites

ATST test tower

Dimensions of ATST Facility (section view)

Enclosure (dome)

LowerEnclosure

Support & Operations

13

7 f

t.

6’

86 ft.

6’

Existing Mees Observatory

Utility

Main Factors in the size of the Facility:

- Locate telescope above the heat & dust near the ground

Pier66’ x 67’ high

78

ft.

92 ft. high

- Enough space for telescope to rotate with overhead room for maintenance

- A platform lift for the 4.2 m (14 ft.) primary mirror & for large instruments

- A pier big and stable enough for a very rigid foundation on volcanic gravel.

- Space inside the pier for a rotating instrument platform.

- Support building big enough for operating & maintaining the telescope, preparing instruments for use, and for equipment that needs to be close

- Utility building for a back-up generator and cooling equipment

fan

fan

tunnel

u tility sha ft

vehi

cula

r ac

cess

?

icetanks

generator

ExistingCistern

support & operations building

Receiving &Mirror Prep

offices

existing Mees solar observatory

kitchen

Expanded Shop

lab

utility building

existing main observatory road

service &parking area

plenum

EquipmentArea

Platform Lift

Base ofPiers

concrete pier

MirrorCoatingFacility

ventilation

lowerenclosure

ups

ups

ups

cond.

n

ewX

-fo

rmer

hatch

chillers

1050

0 5

30 ft.

10 m

north

Notes:- Building orientation and layout based on CFD analysis and site space restrictions.

- Elevation of ground floor level is 9983' (~4 ft. higher than Mees building floor level)

wastetreatmentplant

50' turning radiusfor trucks

34 m

11.

8 m

controldimensions

elev.

exteriorutility area

thermalground shield(3 m high)

mirror box

20

Building Layout Plan

~78 ft.

View of ATST from Northwest

Materials & Appearance

All exposed exterior surfaces painted white to minimize solar heating

- On critical areas of the dome “Plate-coil” panels with liquid coolant flowing inside to keep surfaces equal to air temperature

- Large ventilation windows to allow wind to blow through

- Plate-coil awnings to shade telescope and dome interior from direct sunlight

- Support building with standard metal building panels on roof & walls

Utility building painted to blend with volcanic rock

Catwalk

Perforated panels to allow air cooling of lower enclosure

White concrete apron for heat shield

- Heat exhaust fans with sound mufflers

Mees

Summary of Site & Building Characteristics

• The two potential sites– At good seeing locations on the existing compound– Enough available area for the proposed ATST facility

• Enclosure would be the most dominant visual element– High enough to allow good seeing conditions for the telescope– Large enough to allow telescope to rotate inside– White to minimize solar heating of surface

• Support & Operations Building– Near the telescope, so also white– Just large enough for telescope-related activities– Existing Mees structure re-utilized for some ATST functions

• Utility Building– Allows remote location and exhaust of heat from surfaces & equipment– Sound insulated and painted brown

ATST Schedule OverviewFY2009 Start

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Site ConstructionSite Construction

Telescope & InstrumentIntegration & Commissioning

Telescope & InstrumentIntegration & Commissioning

NSF Cost Review

NSF PanelReview

Site EIS ProcessSite EIS Process

Technology DevelopmentTechnology Development

Concept & DesignConcept & DesignDesign to

Construction Bridge

Design toConstruction Bridge

SDRs

MREFC “Readiness”

ConstructionProposal

Proposed Site Decision

NSF PDR

MREFC Panel “Exit Readiness Review”

NSB

NSF FDR

OMB &Congress

Why an ATST?

Theory and Modeling have gone beyond our ability to test observationally

a b c

a. Numerical simulation of magneto-convection (courtesy of Fausto Cattaneo

b. As viewed with a diffraction limited4-m telescope

c. As viewed with a diffraction limited 1-m telescope

1.1”

Major Questions ATST will Address

• How are the highly intermittent magnetic fields observed at the solar surface generated by dynamo processes and how are they dissipated?

• What magnetic configurations and evolutionary paths lead to flares and coronal mass ejections?

• What mechanisms are responsible for variations in the spectral and total irradiance of the Sun?

Flux Tubes:

DST w/ AO

6 sec exposure G-band

:

The ATST Will:

• Clearly resolve fundamental astrophysical processes at the spatial scale needed to test models

• Provide a high photon flux for accurate and precise measurements of physical parameters throughout the solar atmosphere

– High signal to noise spectro-polarimetry of magnetic field on its elemental scale– Measure magnetic strength and direction, temperature and velocity, on the short

time scales of the dynamic solar atmosphere

• Directly measure coronal and chromospheric magnetic fields• Observationally test models of:

– Magneto-convection– Flux emergence and annihilation– Flux transport– Flux tube formation and evolution– Sunspot magnetic fields and flows– Atmospheric heating– Solar Activity

• Enable, complement and enhance planned space missions

Progress in Solar Physics Needs:

• More Quantitative Data: – Full Stokes Vector Polarimetry– Full line spectroscopy with good spectral resolution

• A “Systems Approach” to get a (more) complete picture– Multi-line, multi-wavelength observations– NIR, Thermal IR

• Better Spatial Resolution!• Higher Temporal Resolution!• Photons, Photons !!!

We need the ATST

Larger Aperture

4m Aperture Solar Telescope withAdaptive Optics

• Unique tool to study the Sun

• Will replace major existing Solar Facilities

• Expected lifetime 30-40 years

• Addresses scientific challenges of today

• Look ahead when defining requirements (e.g. Multi Conjugate Adaptive Optics)

• Able to adapt to new scientific challenges

• Flexibility/Adaptability

fan

fan

tunnel

u tility sha ft

vehi

cula

r ac

cess

?

icetanks

generator

ExistingCistern

support & operations building

Receiving &Mirror Prep

offices

existing Mees solar observatory

kitchen

Expanded Shop

lab

utility building

existing main observatory road

service &parking area

plenum

EquipmentArea

Platform Lift

Base ofPiers

concrete pier

MirrorCoatingFacility

ventilation

lowerenclosure

ups

ups

ups

cond.

n

ewX

-fo

rmer

hatch

chillers

1050

0 5

30 ft.

10 m

north

Notes:- Building orientation and layout based on CFD analysis and site space restrictions.

- Elevation of ground floor level is 9983' (~4 ft. higher than Mees building floor level)

wastetreatmentplant

50' turning radiusfor trucks

34 m

11.

8 m

controldimensions

elev.

exteriorutility area

thermalground shield(3 m high)

mirror box

20

Building Layout Plan

~78 ft.

Schedule Overview

• What is the current schedule?

• When would construction begin?

• When would operations begin?

Jeremy Wagner - Project ManagerMarch 2006

Building Requirements

Astronomers & the public want observatory buildings to be small & invisible.

Engineers & architects define what is needed for protection, operation & maintenance of the telescope, and design minimal-impact structures to suit.

Enclosure (dome):

- Protect the telescope from wind & rain.

- Provide space and equipment to maintain the telescope.

- Prevent solar heating dome skin and other surfaces close to the telescope.

- Allow flow-through natural ventilation of the area around the telescope.

- Allow accurate tracking of the sun through an observing window

Support Buildings:

- Provide space close to telescope and rotating lab for telescope operation & scientific activities

- Provide space for related administrative & maintenance activities and for equipment

- Do not harm the “seeing” quality - Put buildings downwind of telescope - Avoid solar heating of surfaces - Exhaust heat from equipment away from the telescope

ATST Collaboration

• PI– National Solar Observatory

• Co-PIs– High Altitude Observatory – University of Hawaii – University of Chicago – New Jersey Institute of Technology

• Collaborators– 22+ Universities and Institutions

• International Partnerships