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With three probes launched toward Mars in the last two weeks, including the UAE’s Hope, the red planet has captured everyone’s attention. People have suddenly discovered a fascinating planet, with blue sunsets, dust storms that can cover thousands of kilometers, a thin atmosphere with lots of carbon dioxide and some amount of water vapor, liquid water underground and icy lakes on the surface, and much more. And people have marveled at the complex instruments carried by Hope and the other probes.
Indeed, astronomy has changed so much. Telescopes are still standard tools for astronomers, but even Galileo and Newton, who used the first refracting and reflecting telescopes, respectively, would be blown away by the tools and methods we use today to study the cosmos, even nearby planets like Mars.
A brief history of astronomy and its tools should give you an idea of how far we have come — and where things are heading.
The first thing to recall is that, while astronomy is the oldest and most widely practiced of all sciences, only naked eyes were used to observe the planets and the stars for thousands of years — until the early 17th century, when the telescope was invented. Then progress was made with bigger and bigger telescopes being built, which allowed for celestial objects to be observed with greater detail and at farther distances.
The next revolution occurred in the early 19th century, when it was realized that light from the sun, the moon and even planets and stars could be spread out through a prism and analyzed (which colors were dominant or missing), thus providing important information about the object. With this spectroscopy, astronomy became astrophysics, as we could suddenly explore objects (contents, temperatures, etc.) from afar and not just measure their positions and motions.
Astronomy is not the stereotypical romantic but useless ‘looking at the stars’ activity — not today, not even in the past.
Nidhal Guessoum
The 20th century can be regarded as the century of space, as rockets allowed us to reach beyond the Earth’s atmosphere and place satellites up there. Satellites now give us vital information about our planet and whatever else we make them observe out there. Most importantly, instruments aboard satellites can catch non-visible light, e.g., X-rays and microwave radiation, as well as infrared and ultraviolet radiation, most of which the atmosphere blocks from us here on the ground. Now we can observe cosmic objects with all their characteristics, not limited by our eyes or by our planet’s atmosphere.
And, by the 21st century, astronomy added not just non-visible light and radiation, but also various particles, transforming itself into “multi-messenger” astronomy. Now we can also catch cosmic rays and neutrinos (elusive particles that require kilometer-size detectors to catch).
If that was not impressive enough, in 2015, gravitational waves were detected, using four-kilometer-long lasers. To appreciate the feat, one may recall that Albert Einstein himself, who predicted these waves, quickly noted how feeble they are and thus concluded that they would not be detected in the foreseeable future. Not only have they been detected — a good dozen times in the last five years — but we now have entire networks of telescopes (such as the humorously named GRANDMA, Global Rapid Advanced Network Devoted to the Multi-messenger Addicts) participating in this multi-messenger astronomy. Using these and other instruments, astronomers observe cosmic objects and phenomena using light, both visible and non-visible, as well as gravitational waves, cosmic rays and neutrinos.
This might sound like very advanced and sophisticated research, not the stuff we and our students could be doing in our region. In fact, we have students from the Gulf and the Arab world currently participating in such multi-messenger observations and discoveries, taking part in conferences, and publishing research papers.
I know from experience that astronomy and space science is a field that fascinates and strongly attracts students as well as the general public, even more so when they appreciate how rich and diverse it has now become. But, more than that, students get excited when they realize they can really take part in such front-line research and contribute some (worthy) efforts.
Astronomy is not the stereotypical romantic but useless “looking at the stars” activity — not today, not even in the past. Astronomy has integrated a large suite of tools that allow it to study various topics and phenomena, from Martian underground water (using radars carried by orbiting probes) to gold and other elements produced in the merging of neutron stars hundreds of millions of light years away.
The cosmos — and with it astronomy — have become more fascinating than ever thanks to the addition of new instruments, the collaboration and networking of dozens of observatories on the ground and on satellites, and the participation of thousands of enthusiastic students and specialists around the world. In fact, even amateurs often make valuable contributions.
The sky is open to all and the future of astronomy is more wonderful than we can even foresee.
- Nidhal Guessoum is a professor of physics and astronomy at the American University of Sharjah, UAE. Twitter: @NidhalGuessoum