Ultraviolet Telescopes James Green

The Modern Universe Space Telescope A Visions Mission Concept Study for A Large UV-Optical Space Telescope James Green John Bally Matthew Beasley Robert Brown Dennis Ebbets Wendy Freedman John Grunsfeld John Huchra Steve Kilston Randy Kimble Jon Morse Robert O’Connell Kenneth Sembach Michael Shull Oswald Siegmund Erik Wilkinson

Vision Mission Study for a 10 meter optical UV telescope

Science Goals Measurement Capabilities Engineering Implications Key Technologies How are modern galaxies assembled and how do they evolve? How metals are created and distributed through the modern universe? How do stars and planetary systems form and how does this impact their likelihood of supporting life? Where are the baryons in the modern universe and how are they distributed?  Sensitivity to V = 29 stars in hour-long exposures  100 independent resolution elements across a one arcsecond galaxy at z ~ 2  Large field of view for efficient sky coverage  Narrow filters suitable for studying gas processes in both local and extragalactic environments  Separate stars in super star clusters at modest redshift (< 0.2) (0.01 arcseconds)  Measure proper motion of 10 kms -1 out to 8 kpc  Resolve scales of 4.5 AU at Orion (0.01 arcseconds)  High contrast imaging  UV/Optical spectroscopy of m v = 21 objects at  > 20,000  Multi-object spectroscopy  Integral Field Spectroscopy Detectors Large format, high QE arrays for NUV-Visible High QE large format UV photon counting detectors Radiation tolerant detectors Optics 10 meter primary, segmented primary Diffraction limited at 500nm Low UV scatter optics High throughput UV/Optical spectrograph Tunable filters for arbitrary bandpass selection. Miscellaneous Fine pointing/ correction (< 1 mas) Extremely large data volume drives telemetry systems Efficient maneuvering of large, massive observatory Detectors 4 edge buttable NUV/Visible solid state devices High resolution, large format anodes for microchannel plate detectors Improved microchannel plates for lower gain/higher count rate applications Improved photocathodes for microchannel plate based detector systems Higher efficiency for solid state detectors Optics On orbit assembly and verification process for large optics Coronagraphy with segmented primary optic Coating techniques for large optics Tunable filter technology applied to large sizes for space based systems

Imaging Instruments High Resolution Camera: High Resolution Camera: 0.01" resolution over a 300" x 300" FOV 0.01" resolution over a 300" x 300" FOV (10 gigapixel " per pixel) (10 gigapixel " per pixel) Wide Field Camera: Wide Field Camera: 0.03" resolution over a 1500" x 1500" FOV 0.03" resolution over a 1500" x 1500" FOV (10 Gigapixel 0.015" per pixel) (10 Gigapixel 0.015" per pixel)

0.01 arc second imaging HST z ~ 0, today NHST z = 1.5, ~ 9Byr ago JWST z = 4, ~11Byr ago

0.01 arc second imaging Resolution at Orion = 4.5 AU Resolution at Taurus = 1.4 AU

Spectroscopic Instruments Multi-Object Spectrograph and Integral Field Spectrograph – Multi-Object Spectrograph and Integral Field Spectrograph – Up to ~1000 simultaneous spectra in the data cube – either critically packed (IFU) or low density sampling (MOS) Up to ~1000 simultaneous spectra in the data cube – either critically packed (IFU) or low density sampling (MOS)

Can VSE enable these goals? If the primary purpose of NASA was to launch a 10 meter optical-UV telescope, we would not choose to go to the moon - If the primary purpose of NASA was to launch a 10 meter optical-UV telescope, we would not choose to go to the moon - However, it is not the primary purpose of NASA to launch a 10 meter optical-UV telescope – and we are going to the moon However, it is not the primary purpose of NASA to launch a 10 meter optical-UV telescope – and we are going to the moon

Going to the moon will require substantial infrastructure The primary technical limitations in mission design are mass and volume – particularly fairing diameter The primary technical limitations in mission design are mass and volume – particularly fairing diameter Any moon launch vehicle will have plenty of both Any moon launch vehicle will have plenty of both

Last time we went to the moon

Saturn V capabilities 260,000 lbs to LEO 260,000 lbs to LEO 100,000 lbs to trans-lunar 100,000 lbs to trans-lunar Designed with single-mindedness “To take a man to the moon and return him safely before then of the decade”

However, the Saturn V could and did do more -

84 feet long 22 feet in diameter

16 Imagine if that had been a telescope! 1.9m (PAF) 13.1 m (Dispenser) 9.8 m Robotic Volume Secondary Assembly Tray’s for Attachable Mirror Pedals Sun Shield Assembly Spacecraft Bus Comm. Antenna (s) Stowed Solar Array

The vision aims to bring the solar system into our economic sphere This means the launch capabilities must have some flexibility – cargo capacity – space walking This means the launch capabilities must have some flexibility – cargo capacity – space walking We cannot drive the specifications of the system, but can we nudge them? We cannot drive the specifications of the system, but can we nudge them?

What would we want? As large a diameter fairing as possible: What is the cost/benefit of a bulbous fairing for astronomy? What is the cost/benefit of a bulbous fairing for astronomy? Ability to service telescopes: Docking and EVA capability Docking and EVA capability Ability to travel to locations other than the moon: - Earth/Moon L1, Lunar orbit, Sun/Earth L2? - Earth/Moon L1, Lunar orbit, Sun/Earth L2?

Now is the time Now is the time to be participatory, and press for capabilities for Astronomy in general, and not for any specific mission Now is the time to be participatory, and press for capabilities for Astronomy in general, and not for any specific mission While I do not want to dismiss the difficulty in affecting the process, it will only be harder later While I do not want to dismiss the difficulty in affecting the process, it will only be harder later

Will we treat the vision the same way? What capabilities might the ISS have now, what astronomy missions might it currently support, if it had been designed with these needs up front. The astronomy community rejected the ISS from the start, and opposed its development and now it is useless to us

If we put a telescope on the surface

We should use the ground based paradigm – not the space mission paradigm We should use the ground based paradigm – not the space mission paradigm A facility on the moon – multi-wavelength, multi-capable, upgradeable, repairable, and utilizing the manned presence A facility on the moon – multi-wavelength, multi-capable, upgradeable, repairable, and utilizing the manned presence

VSE is an opportunity A new infrastructure to launch large, heavy and complex payloads is being developed A new infrastructure to launch large, heavy and complex payloads is being developed This may well include the ability to sustain manned operations beyond low earth orbit This may well include the ability to sustain manned operations beyond low earth orbit If we cannot find a way to utilize this capability to perform cutting edge astronomy, than something is wrong. If we cannot find a way to utilize this capability to perform cutting edge astronomy, than something is wrong.