Spotlight Live: The Hunt for Distant Galaxies
NOTE: Thanks to everyone who joined our discussion. YOUR QUESTIONS are listed below with time stamps for hearing the answers.
ASTRONOMERS KNOW there are vast numbers of galaxies waiting to be discovered, and the more they find the more we’ll understand about how the universe began and evolved. Unfortunately, many galaxies are incredibly far away, vanishingly faint and hidden behind other clusters of galaxies.
Under the right circumstances, however, it’s actually possible to see behind a galaxy cluster – a seeming magic trick made possible when the gravity of a cluster in the foreground bends and magnifies the light from a galaxy behind it. That warped light continues on its way toward Earth, and it can be detected in our telescopes. This phenomenon means there are clusters of galaxies that act as giant magnifying glasses that allow us to see galaxies far beyond them. And the deeper into the universe we can look, the farther back into cosmological time we can see.
Using entire galaxies as lenses to look at other galaxies, researchers have a newly precise way to measure the size and age of the universe and how rapidly it is expanding, on a par with other techniques. The measurement determines a value for the Hubble constant, which indicates the size of the universe, and confirms the age of the universe.
That brings us to the Space Warps citizen science project. Finding these distant magnified galaxies is a daunting challenge. The universe is vast, with billions of galaxies to find and only so many astronomers to look for them. So they need your help. A team of astronomers tells you how you can spot this strange, light-warping effect in images taken by telescopes across the globe. View the conversation recorded on June 5, and then take part in the search for some of the most distant galaxies in the universe at www.spacewarps.org.
About the Participants (left to right)
ANUPREETA MORE is a postdoctoral fellow at the Kavli Institute for the Physics and Mathematics of the Universe at the University of Tokyo. Dr. More is a co-Principal Investigator of Space Warps, a citizen science project with Zooniverse. She is leading the first Space Warps project using data from the Canada-France-Hawaii Telescope Legacy Survey. She completed her PhD in Astronomy from the Max Planck Institute for Radio Astronomy (MPIfR) at the University of Bonn, Germany.
PHILIP MARSHALL is a researcher at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC). Dr. Marshall recently moved to KIPAC from the University of Oxford, where he was a Royal Society Research Fellow in the University's Department of Physics. His primary research interests include observational cosmology, including weighing galaxies and measuring the expansion rate of the Universe. He is involved in a number of surveys to find new galaxies using both ground-based and space telescopes.
ARFON SMITH is Director of Citizen Science at the Adler Planetarium in Chicago and Technical Lead of Zooniverse (www.zooniverse.org). Dr. Smith leads a team of developers, educators and scientists who build citizen science projects across a range of disciplines, including astrophysics. He earned his PhD in Astrochemistry from The University of Nottingham in 2006, and he subsequently worked as a senior software developer at The Wellcome Trust Sanger Institute in Cambridge (UK). In 2008, Dr. Smith joined the Zooniverse team at the University of Oxford, and he has coordinated the development of more than 20 citizen science projects. Today, more than 800,000 volunteers participate in Zooniverse projects.
BRUCE LIEBERMAN is a freelance journalist with more than 20 years of experience in the news business. He worked as a reporter at daily newspapers for many years before becoming an independent writer and editor in 2010. For The Kavli Foundation, Bruce has interviewed researchers about galaxy clusters, dark matter and dark energy, string theory, the emergence of the first stars and galaxies, exoplanets and other subjects. He has also written for Scientific American, Smithsonian Air & Space magazine, and Nature about a variety of science topics.
On June 5, science writer Bruce Lieberman asked your questions about spacewarps.org and the hunt for distant galaxies in an interview with Anupreeta More, Phil Marshall and Arfon Smith.
- What is spacewarps.org? (2:50)
- Why is gravitational lensing important for astrophysics? (7:05)
- Will we need any software to use spacewarps.org? (8:00)
- How do I know I'm looking at a gravitational lens? (9:15)
- How can teachers use this with their students? (10:15)
- What is gravitational lensing in simple terms? (11:50)
- What causes the gravitational lensing effect? (16:10)
- Are there more galaxies looking in one direction of the sky, over another? (17:00)
- How do you register for spacewarps.org? (18:15)
- Is there a center to the universe? (21:05)
- What is the most mysterious thing about a galaxy? (21:55)
- What new things are we discovering about galaxies? (24:10)
- What is our current understanding of gravity and dark matter? (26:10)
- How many dimensions are there? (28:00)
- Does spacewarps.org work like a telescope? (29:00)