World’s Largest Optical/Near-infrared Telescope (E-ELT) Will Be Built With New, Advanced, Powerful Cameras

This video presents “E-ELT Trailer.”

ESO (the European Southern Observatory) has been planning a 39-metre-class European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

• ESO just started the construcion of the European Extremely Large Telescope (E-ELT) with a groundbreaking ceremony on 19 June at Cerro Armazones, near Paranal in Chile.
• The telescope’s “eye” will be almost half the length of a soccer pitch in diameter.
• The start of operations is planned for early in the next decade, 2024.
• More than 100 astronomers from all European countries have been involved throughout 2006 on the planning and design of the E-ELT.

The costs involved are astronomical!

• This planning/designing study costs 57 million Euros (77,512,590.00 US Dollar at the current exchange rate).
• The construction cost is estimated to be 1083 million euros (2012 prices; 1,472,739,210.00 US Dollar at the current exchange rate).
• The E-ELT will be operated as an integral part of the ESO observatories.
  • The operating cost includes not only the cost of running the observatory in Chile, but also the cost of operation support in Garching as well as re-investment costs for telescope upgrades and new instruments/cameras for the telescope.
  • The total operating cost is estimated to be 50 million euros per year (67,993,500.00 US Dollar per year at the current exchange rate).

The E-ELT will be the largest optical/near-infrared telescope in the world and will gather 15 times more light than the largest optical telescopes existing today.

• This revolutionary telescope will be able to correct for the atmospheric distortions (i.e., be fully adaptive and diffraction-limited) from the start, providing images 15 times sharper than those from the Hubble Space Telescope.
• The E-ELT can observe over a wide range of wavelengths from the optical to mid-infrared.

The new, advanced, powerful cameras that will be built as part of the European Extremely Large Telescope include:

ELT -CAM Instrument

• The diffraction – limited NIR (Near Infrared) imager, ELT -CAM, is based on MICADO which is the acronym for Multi-AO Imaging Camera for Deep Observations.
  • It is designed to work with AO (adaptive optics) on the E-ELT.

• It’s an infrared (0.8 – 2.5 μm) camera designed for performing astrometry as well as obtaining exquisite photometry of dense, resolved stellar populations at the highest possible spatial resolution.
  

  “MICADO is one of the two instruments that are currently defined by ESO as the First-Light Instruments (one camera and one spectrograph) for the E-ELT. The 39-Meter telescope will be begin its operation with this camera which obtains for the first time stellar light for analysis.”

  Institute for Astrophysics
  http://www.uni-goettingen.de/en/263488.html

• This wide-field imaging camera is very compact and is supported underneath the AO systems so that it rotates in a gravity invariant orientation (please see Fig.1 below).
• This adaptive optics camera is able to image, through a large number of selected wide and narrow band near-infrared filters, a wide 53″ field of view at the diffraction limit of the E-ELT.
  • The field of view of the camera should be comparable with the 53 arcseconds x 53 arcseconds field of MICADO.
•  It is also a high throughput camera with a fixed 3 mas (milli-arcsec) pixel scale,
• The key capabilities include the following:
  • Higher Sensitivity and Resolution.
    • This is a powerful tool for many science cases, from studies of faint high redshift galaxies to performing photometry in crowded fields (please see Fig.3 below).
  • Precision Astrometry.
    • The primary imaging field of the camera uses only fixed mirrors.
  • High Throughput Spectroscopy.

ELT – MIR Instrument

• ELT – MIR is based on METIS (Mid-Infrared E-ELT Imager and Spectrograph) for the thermal infrared (2.9 μm –14 μm) region to:
  • image young, self – luminous giant planets,
  • study the molecules present in their atmospheres as well as their weather,
  • study our Solar System in more detail than ever before, from cometary volatiles to the surface of Kuiper Belt objects,
  • image both the gas and dust distribution  of planets, and
  • get the dynamics and composition via spectroscopy.

ELT – PCS Instrument

• ELT – PCS is The E-ELT Planetary Camera and Spectrograph, which is based on EPICS.
  • The spectrometer optical design has a six lens collimator and five lens camera which focuses the light on a mosaic of four 4k x 4k detectors.
  • It is designed for:
    • imaging exoplanets – young, self-luminous planets in star-forming regions or young clusters as well as
    • imaging and characterisation of earth-like planets in the habitable zone.

ELT-IFU Instrument

• ELT-IFU is based on HARMONI, which has high spatial resolution and will allow researchers to:
  • fully characterise Jupiter-mass exoplanets by determining their age, mass and temperature,
  • study the low – mass regime of star formation,
  • understand the transition between planet and brown dwarf formation,
  • probe the vicinity of intermediate – mass black holes in star clusters and dwarf galaxies, thought to be possible seeds of supermassive black holes at high redshift, and
  • allow the study of resolved stellar populations in nearby galaxies.

Please click here for more details and the roadmap of the E-ELT instruments.

Here are some highlights of the the world’s largest optical/near-infrared telescope.

The mirror design itself is revolutionary and is based on a novel five-mirror scheme that results in an exceptional image quality.

• Five-mirror design: three-mirror on-axis anastigmat + two fold mirrors used for adaptive optics.
• Primary M1 is a mirror 39 metres in diameter, covering a field on the sky about a tenth the size of the full moon.
  • Pimary M1 will be composed of 798 hexagonal segments, about 1.4 metre wide and 5 cm thick.
  • Light collecting area: 978 square metres.
• The optical design calls for an immense secondary mirror, M2, which is 4 metres in diameter and bigger than the primary mirrors of any of ESO’s telescopes at La Silla.
• Tertiary mirror M3 is 3.75 metres in diameter.

Adaptive mirrors (optics) are incorporated into the optics of the telescope to compensate for the fuzziness in the stellar images introduced by atmospheric turbulence.

• Adaptive optics (AO) are sophisticated, deformable mirrors controlled by computers and can correct in real-time for the distortion caused by the turbulence of the Earth’s atmosphere, making the images obtained almost as sharp as those taken in space.
  • One of these mirrors is supported by more than 6000 actuators that can distort its shape a thousand times per second.
• AO require a fairly bright reference star that is very close to the object under study.
  • Since suitable stars are not available everywhere in the night sky, astronomers can create artificial stars instead by shining a powerful laser beam into the Earth’s upper atmosphere (as shown in the above photo “Shooting a Laser at the Galactic Centre”).
  • Thanks to these laser guide stars (2.60 metres adaptive M4 mirror using 6 Laser Guide Stars), almost the entire sky can now be observed with AO.

It will be possible to switch from one science instrument to another within minutes.

• The telescope and dome will also be able to change positions on the sky and start a new observation in a very short time.

The European Extremely Large Telescope will also be used to:

• make an inventory of the changing content of the various elements in the Universe with time,
• understand star formation history in galaxies,
• search for possible variations in the fundamental physical constants with time in regards to the general laws of physics,
• study the nature and distribution of the dark matter and dark energy which dominate the Universe, and
• measure the acceleration of the expansion of the Universe directly.

As the E-ELT will have a much larger sensitivity and resolution than the current generation of large telescopes, it will certainly be most useful in the study of faint objects in the Solar System.

• This super telescope will gather 100 000 000 times more light than the human eye,
  8 000 000 times more than Galileo’s telescope, and 26 times more than a single Very Large Telescope (VLT) Unit.
  • In fact, the E-ELT will gather more light than all of the existing 8–10-metre class telescopes on the planet, combined.
• Compared to VLT, for the E-ELT the “aperture” is fully filled at all times.

“One of the highest scientific priorities for the telescope is to characterise exo-planets and, specifically, to take images of Earth-like planets. Such a giant leap from the capabilities we have today requires significant research into new technologies over several years. Therefore, an ambitious and powerful planetary camera and spectrograph (ELT-PCS) is included in the instrumentation plan, and the research and development for specific components required to build it will start as soon as possible.”

European Southern Observatory
http://www.eso.org/sci/facilities/eelt/docs/E-ELT-Construction-Proposal-INS-Chapter.pdf

The main goal of the E-ELT programme is to scientifically answer the question “are we alone?”