While the Hubble Space Telescope has entered the annals of even our pop culture, the space-borne contraption (making its debut in 1990) is surely feeling its age, with its operational capacity expected to expire by 2020. So the question remains – what then? Well, one of the potential candidates to fill in its imminent shoes might be the ‘lens-less’ Aragoscope designed by a team at the University of Colorado Boulder. And interestingly, the device’s core design deviates from the conventional application of mirrors in telescopes, by integrating a gargantuan orbital disk in its stead.
Christened after French scientist Francois Arago who first observed the diffracted effects of light waves caused by disks, the Aragoscope is actually based on this primary principle. In essence, the space-borne telescope’s huge disk will be utilized as a diffraction lens, which in turn will aid in ‘bending’ the light waves from the distant objects around its edge regions. This will ultimately be focused to converge upon a central point (like a regular refraction lens) – thus transforming the telescope into an incredibly powerful device with a capacity of producing 1,000-times sharper images than Hubble. As one of the team-members (and doctoral student) Anthony Harness makes it clear –
The opaque disk of the Aragoscope works in a similar way to a basic lens. The light diffracted around the edge of the circular disk travels the same path length to the center and comes into focus as an image.
To that end, the opaque disk of the Aragoscope will be a whopping half-mile in diameter, envisaged to be crafted from a high-strength plastic-like material and then launched into space like a unfolding parachute (from a compressed form). The orbiting telescope-carrying station would be tethered to this disk at distances ranging from ten to hundreds of miles – depending upon the size of the opaque object. So, the working scope would entail the collection of the light (at the focal point) by the station, and its subsequent conversion into high-resolution images. And quite advantageously, the logistical launch of such a lightweight yet large disk would help in gathering sharper images, since resolution is directly proportional to the diameter of the telescope.
In line with all these advanced features, it doesn’t really comes as a surprise that the Aragoscope was chosen as one of the 12 entries for NASA Innovative Advanced Concept (NIAC) program. Judged on the progressive status of the endeavor, the project will now receive funds of $600,000 by April. This monetary backing will be used for a testing phase that will initially involve a meter-long diameter disk, and will later entail a bigger disk being installed atop a mountain (and the telescope being fixed on a helicopter). And further down the pipeline, the final design of the Aragoscope is expected to have a capacity to observe distant space-based phenomena like black hole event horizons and even plasma exchanges between stars.