Technological aids for future research
To aid their quest in the future, scientists can rely on an ever increasing number of technological aids, at the forefront of which is the Large Hadron Collider[0].
Despite all the fine work it has done, the Hubble Space telescope will be rendered obsolescent in 2021 by the James Webb Space telescope (JWST) positioned approximately one million miles from earth, far beyond Hubble’s low Earth orbit. At 6.5 metres in width, the JWST’s combined 18 optical mirrors will be almost 3 times the diameter of Hubble’s primary mirror. The larger diameter will collect more light to allow scientists to see farther and better than Hubble. In fact, for the first time scientists for the first time will be able to see back to almost the very beginning of time.[1]
However, it has a planned lifetime of only 5 to 10 years before it runs out of he fuel it needs to maintain its orbit. By way of comparison Hubble is still going strong after 28 years (as at 2018). JWST is due to fly about a million miles from earth, much too far for astronauts to service, repair or add new instruments to it, as they did several times for Hubble. Using the technique of gravitational lensing, JWST will be the key to discovering some of the earliest galaxies in existence, including the smaller galaxies we can't see at the moment using the lensing technique via Hubble and the Spitzer Space telescope. [2]
In the years to come a High-Definition Space Telescope (HDST) is proposed with the capacity to make observations, as Hubble does, at optical, ultraviolet and near-infrared wavelengths. James Webb will be deficient in the ultraviolet range. HDST's mirror would have the capacity to resolve structures about 300 light years across in galaxies on the opposite side of the visible universe: useful for understanding star formation, as well as the nature of dark matter and dark energy. It would also facilitate the examination of Earth size exo-planets for signs of alien life. If it gets going, the HDST could be in the skies as soon as the early 2030s. However, the likely cost outlay could prevent it getting ever off the ground.[3]
In the meantime, more than a dozen spacecraft are now in orbit complementing Hubble observations:
- The Chandra X-ray Observatory and Spitzer and Fermi Gamma-ray space telescopes;
- The Wilkinson Microwave Anisotropy Probe (WMAP), which has made fundamental measurements of the properties of our universe as a whole;
- The Galaxy Evolution Explorer, which generates an ultraviolet sky survey of galaxies;
- The Kepler space probe, launched in May 2009 was the world’s first mission to search for exoplanets - planets that orbit stars like our Sun or similar, peering into the so-called “habitable zone” – the region around a star where the temperature is just right for liquid water, an essential ingredient for life. Unfortunately, the telescope temporarily stopped collecting data in 2013 after a mechanical failure. However, by the end of its working life, it had detected nearly 5,000 candidates, with more than 3,500 of those confirmed as actual planets. One of its most notable discoveries was Kepler 186f, located more than 500 light years from Earth and the outmost of five planets orbiting its star. The orbits of the four inner planets were too close to the star and therefore too hot to harbour liquid water. The diameter of Kepler 186f is 14,000 km, just 10% larger than the earth. It takes 130 days to complete one orbit compared to the earth’s 465 days. It is considered more a cousin of the Earth than a twin[4]. As revealed in the substantive text, it is soon to be replaced by TESS and CHEOPS to be launched in 2018.
- The Planck telescope launched in May 2009 aboard an Ariane 5 rocket from French Guiana to map the cosmos and analyse its origins. It is positioned at a location in space known as the Earth/Sun Lagrange point some 1.5 million kilometres from Earth. In March 2013, it was reported to have captured an image of the residual glow from the Big Bang.[5]
- The recently launched Wide-field infrared Survey Explorer will allow scientists to survey the entire sky in the mid-infrared with far greater sensitivity than any previous mission. It will image and catalogue a vast number of astronomical objects, which will provide a storehouse on information about our solar system, our galaxy the Milky Way, and the universe as a whole;
- The Nuclear Spectroscopic Telescope Array (NuSTAR), launched June 2012, which will expand our understanding of the origins and destinies of stars, galaxies and black holes, and will have 500 times the sensitivity of previous instruments to detect black holes. It will map supernova explosions, and study the most extreme active galaxies. Using advanced technologies, it will help to preserve a balance between small and large missions in NASA’s astrophysics portfolio[6].
- The Square Kilometre Array, a gigantic radio telescope planned for 2020 as part of a joint project between Australia and South Africa, will survey all the galaxies within our observable horizon.
- And let us not forget two old friends, the Voyager 1 and 2 space craft, which as at November 2012, have now been operating in excess of 35 years. Originally, launched in April 1977, the probes’ planetary tour was expected to last just five years. Between them, they have since explored Jupiter, Saturn, Uranus and Neptune, 48 of their moons and the rings and magnetic field some of these planets possess. They have now moved on to the heliosheath, the outermost layer of the heliosphere and the edge of our solar system, a place where no man made object has previously reached, and are headed into deep space, still communicating all the while. Travelling at about 520 and 470 million kilometres per year respectively, they are now 17.9 and 14.7 billion kilometres from our sun, and even at that rate it will be another 700 centuries before it has travelled the distance to our nearest star . The instruments of both craft will continue to measure ultraviolet sources among the stars, and are expected to return data to Earth for two more decades until their plutonium power sources run out[7].
And of course, there are many others referred along the way on this webpage. With the aid of this comprehensive array of technology, the time may not be too far distant when we will not only be able to see back to near the very beginning of time itself, but also to determine whether there are other life forms beside our own out there in the universe. We have come a long way since Ptolemy and Aristotle once thought earth was the centre of the universe, and we would do well to remember that that was not all that long ago.
After some three thousand years of earth-centred astronomy, we have now been kicked out of our prime position centre stage. We now know that our planet is nothing more than an insignificant speck in the cosmos[8], and that the stuff of which we are made, protons and neutrons, comprises a mere 5% of the cosmos. What is truly extraordinary in this context is that after only 400 years of modern science, humankind has been able to create a remarkable body of knowledge that stretches all the way from the inner confines of atomic nuclei to galaxies billions of light years away[9]; and “that beings confined to one planet orbiting a run-of-the-mill star in the far edges of a fairly ordinary galaxy, have been able, through thought and experiment, to ascertain and comprehend some of the most mysterious characteristics of the physical universe”[10].
[0] The Large Hadron Collider (link on previous page).
[1] Weiler, Hubble, 139. The original cost schedule was for launch in 2001 at an estimated cost of $1.6 billion. Current estimates are for launch no earlier than October 2018 at a cost of $9 billion: Lee Billings, "Go big or go home", Scientific American, July 2015, 9-10.
[2] Dan Coe, "Back in time", Scientific American, November 2018, 34 at 41.
[3] Weiler, Hubble, op cit.
[4] “Astronomers discover Earth-like planet”, SMH, 18 April 2014; Sun-Herald. 20 April 2014. Kepler’s technique was to search for planets by measuring dips in a star’s brightness which occur when a planet passes in front of it, as (in another context) at right.
This so called transiting method is very accurate, but can sometimes throw up a false positive when it comes across an eclipsing binary – a pair of orbiting stars that sometimes cross in front of each other from our perspective: “Kepler’s afterlife”, Scientific American, May 2014, 16.
[5] “Planck telescope captures Universe’s first light”, The Courier Mail (online), 23 March 2013.
[6] Ibid. As to the launch by means of a two-stage aircraft rocket takeoff (more fueld efficient that a launch from the ground), see “Telescope takes hitchhiker’s guide to the galaxy on a plane”, SMH, 15 June 2012, (reproduced from Agence France-Presse).
[7] “Voyager streaks from the limit of knowledge to the universal unknown”, SMH, 6 December 2012, 7.
[8] Albeit “auspiciously placed” in the Goldilocks zone for water to exist in its liquid phase, “the cradle of life’s chemistry”: Gleiser, 156-7.
[9] Gleiser Introduction, xvi.
[10] Greene (2000), 117.