Land based telescopes are better than Space telescopes mostly due to their physical size. Large land based telescopes gather a vast amount of light with their large mirrors and they can be used to survey substantial portions of the night sky. Whereas space telescopes are smaller in size and work with large land-based observatories to look at smaller regions of the night sky in plenty of detail.
Justified scientific arguments using Evidence
Land Based telescopes catch light waves and the larger a telescope is ‘the more light it can catch and the better the sharpness of the image becomes’ (Kudritzki in Osterath, 2015). Hence large land based telescopes enable astronomers to detect fainter objects such as stars and galaxies deeper into the universe and therefore further back into time or the past – because light takes a very long time to reach us on earth from objects far away (Kudritzki in Osterath, 2015).
Examples of the some large land based telescopes include – the Gran Telescopio Canarias (GranTeCan) in the Canary Islands; the Hobby-Eberly Telescope (HET) in Texas; Keck 1 and 2 in Hawaii; The Large Binocular Telescope in Arizona; and the Gemini Observatory Telescopes in Chile. Each of these telescopes are very large and range in diameter from 8.0 m to 10.4 m. There are three other large land based telescopes which are under construction and include the Giant Magellan Telescope (GMT) in Chile; the Thirty meter telescope in Hawaii and the European Extremely Large Telescope (ELT); and each of their diameters range from 24m to 39 meters and are due to start and finish construction over the next seven years. (Das, 2020)
The Giant Magellan Telescope (GMT) is a very large land based telescope equipped with costly and enormous mirrors and optics and it will be able to provide images ten times sharper than the Hubble Space telescope. The GMT will be completed in 2023 and it will give astronomers and researchers the ability to look back further in time more so than ever before (Das, 2020). The adaptive optic systems will produce a single clean image- that will be atmospherically corrected with a very clear resolution of between 6-10 million-arc-seconds and hence the science/physics ‘we are going to learn will be incredible’ (Seigel, 2017). The GMT will lose its claim of being the world's largest observatory to the European Extremely Large Telescope (ELT) with a 978 square metre collection area finishes construction in 2024 (Tarantola, 2017).
The Thirty Meter Telescope (TMT) is a very large telescope with diameter of 30 m and proposed for Mauna Kea in Hawaii and would provide a very large primary mirror to increase resolution and light gathering power simultaneously for Astronomers to observe the universe . The majority of astronomers recognize the Mauna Kea site as a technically superior site for a large telescope due to the high altitude, however in doing so would ignore the objections of many native Hawaiian citizens and hence the TMT has yet to start construction in Hawaii. Some astrophysicists believe the TMT should be built quickly in another location such as Spain, so they can continue exploring and understanding space through using a large telescope in the future such as TMT (Seigel, 2019).
Space telescopes such as NASA’s Hubble Space Telescope, the Compton Gamma Ray Observatory, the Chandra X-ray Observatory and the Spitzer Space Telescope along with large, land-based observatories work together to capture small regions of the sky in great detail. For example NASA's Observatories have worked together to create a 3D representation of the dynamic Crab Nebula which is the tattered remains of an exploded star ('NASA's Great Observatories Help Astronomers Build a 3D Visualization of Exploded Star,'). Hubble’s Space telescope is in a rare position above Earth’s atmosphere and provides exceptional clarity through images as the telescope orbits around Earth. Hence if both astronomers used both space and land-based telescopes and worked together they may be able find complete view of objects in the universe such as the remains of an exploded star (Era: Space Telescopes; Discoveries: Why a Space Telescope).
There are four NASA space telescope concepts which are competing with another to possibly be built and fly in the 2030s. However there are significant costs involved to construct each of the space telescopes, hence there have been no further progress with the following Space Telescopes -The Large UV Optical Infrared Surveyor (LUVOIR); The Habitable Exoplanet Observatory (HabEx); The Lynx Xray Observatory and the Origins Space Telescope (Clery, 2018)
Space telescopes have many disadvantages including being much more expensive to build and launch than land-based observatories/telescopes. Space telescopes must be launched into space, hence they are much smaller than their counterparts in land-based observatories/telescopes. Space telescopes are much smaller than Land based telescopes and therefore they can only look at smaller regions of the night sky in detail when compared with large land based telescopes. And finally, space telescopes generally remain in orbit in the universe, hence making repairs or overhauling the space telescopes can be either extremely difficult or not impossible at all, and when they eventually break down, they’re lost in space forever (Era: Space Telescopes).
Some limitations of the evidence include that there appears to be two main groups of astronomers who support either land based telescopes or space telescopes, yet they appear to have been able to explore more of the universe through collaborating together using both telescopes. Another limitation of the evidence may be that the research and development of all telescopes (especially Space telescopes) is dependent on large amounts of money. Finally, the telescops appear to be the interests of large scientific companies and they are not necessarily designed for further exploration of the universe rather they are promoting a product or a brand of specific optics or mirrors inside a telescope. There was also no evidence/ research to investigate whether large telescopes could be permanently placed on a planet such as Mars for further exploration of our universe.
Large land based telescopes are better than their smaller counter parts/ space telescopes because land based telescopes are able to detect fainter objects such as stars and galaxies deeper into the universe and therefore further back into time. There are many examples of land based telescopes, including – the Gran Telescopio Canarias (GranTeCan) and the Giant Magellan Telescope (GMT). Land based telescopes such as the GMT- will create a single clean image- that’s atmospherically corrected with resolution of between 6-10 million-arc-seconds and hence ‘the science we’re going to learn will be incredible’ (Seigel, 2017).
Space telescopes have a number of disadvantages, including being much smaller and expensive to build and launch than land-based observatories/telescopes. And Space telescopes generally remain in orbit, hence repairs or overhauling them can be either difficult or impossible and when they eventually break down, they will be lost in space forever (Era: Space Telescopes).
An Evaluation the claim
Hence large land based telescopes provide more cost-effective solution to survey large portions of the sky. Furthermore, large land based telescopes are able to observe fainter objects and deeper into the universe. Whereas Space telescopes have many disadvantages, including being smaller, very expensive, and they may have difficulties being repaired and may be lost in space forever. The only obvious advantage of both Land based and Space telescopes is that astronomers can get a more complete view of stars or galaxies through collaboratively sharing their images together (Era: Space Telescopes; Discoveries: Why a Space Telescope).
Suggestions for improvements and extension to the investigation
- Clery, D. (2018, December 13). NASA is Planning Four of the Largest Space Telescopes Ever. But Which One Will Fly? Science | AAAS. https://www.sciencemag.org/news/2018/12/nasa-planning-four-largest-space-telescopes-ever-which-one-will-fly
- Das, B. (2020, January 2). 12 Largest Telescopes in the world | 2020 edition. RankRed. https://www.rankred.com/largest-telescopes-in-the-world/
- Discoveries - Why a Space Telescope? (2019, September 26). https://www.nasa.gov/content/discoveries-why-a-space-telescope
- Era: Space Telescopes. (n.d.). Amazing Space. https://history.amazingspace.org/resources/explorations/landup/lesson/eras/space/page2.php
- NASA's Great Observatories Help Astronomers Build a 3D Visualization of Exploded Star. (n.d.). HubbleSite.org. https://hubblesite.org/contents/news-releases/2020/news-2020-03
- Osterath, B. (2015, October 23). Science with telescopes, size does matter. https://www.dw.com/en/with-telescopes-size-does-matter/a-18784812
- Siegel, E. (2017, January 25). World's largest telescope will revolutionize the future of Astronomy. Forbes. https://www.forbes.com/sites/startswithabang/2017/01/25/worlds-largest-telescope-will-revolutionize-the-future-of-astronomy/#40ff0d5516b4
- Siegel, E. (2019, August 9). Astronomy Faces A Field-Defining Choice In Choosing The Next Steps For The TMT. Retrieved from https://www.forbes.com/sites/startswithabang/2019/08/09/astronomy-faces-a-field-defining-choice-in-the-next-steps-for-the-tmt/#60fe56b44ffd
- Tarantola, A. (2017, November 3). The world's largest telescope will unlock the Universe's oldest secrets. Engadget. https://www.engadget.com/2017/11/03/GMT-worlds-largest-telescope/