ASU astronomers discover faintest distant galaxy

June 1, 2012

Newfound galaxy secures spot among top 10 most distant known objects in space

Astronomers at Arizona State University have found an exceptionally distant galaxy, ranked among the top 10 most distant objects currently known in space. Light from the recently detected galaxy left the object about 800 million years after the beginning of the universe, when the universe was in its infancy. galaxy LAEJ095950.99+021219.1 Download Full Image

A team of astronomers, led by James Rhoads, Sangeeta Malhotra, and Pascale Hibon of the School of Earth and Space Exploration at ASU, identified the remote galaxy after scanning a moon-sized patch of sky with the IMACS instrument on the Magellan Telescopes at the Carnegie Institution’s Las Campanas Observatory in Chile.

The observational data reveal a faint infant galaxy, located 13 billion light-years away. “This galaxy is being observed at a young age. We are seeing it as it was in the very distant past, when the universe was a mere 800 million years old,” says Rhoads, an associate professor in the school. “This image is like a baby picture of this galaxy, taken when the universe was only 5 percent of its current age. Studying these very early galaxies is important because it helps us understand how galaxies form and grow.”

The galaxy, designated LAEJ095950.99+021219.1, was first spotted in summer 2011. The find is a rare example of a galaxy from that early epoch, and will help astronomers make progress in understanding the process of galaxy formation. The find was enabled by the combination of the Magellan telescopes’ tremendous light gathering capability and exquisite image quality, thanks to the mirrors built in Arizona’s Steward Observatory; and by the unique ability of the IMACS instrument to obtain either images or spectra across a very wide field of view. The research, published in the June 1 issue of The Astrophysical Journal Letters, was supported by the National Science Foundation (NSF).

This galaxy, like the others that Malhotra, Rhoads, and their team seek, is extremely faint and was detected by the light emitted by ionized hydrogen. The object was first identified as a candidate early-universe galaxy in a paper led by team member and former ASU postdoctoral researcher Hibon. The search employed a unique technique they pioneered that uses special narrow-band filters that allow a small wavelength range of light through.

A special filter fitted to the telescope camera was designed to catch light of narrow wavelength ranges, allowing the astronomers to conduct a very sensitive search in the infrared wavelength range.  “We have been using this technique since 1998 and pushing it to ever-greater distances and sensitivities in our search for the first galaxies at the edge of the universe,” says Malhotra, an associate professor in the school. “Young galaxies must be observed at infrared wavelengths and this is not easy to do using ground-based telescopes, since the Earth’s atmosphere itself glows and large detectors are hard to make.”

To be able to detect these very distant objects which were forming near the beginning of the universe, astronomers look for sources which have very high redshifts. Astronomers refer to an object’s distance by a number called its “redshift,” which relates to how much its light has stretched to longer, redder wavelengths due to the expansion of the universe. Objects with larger redshifts are farther away and are seen further back in time. LAEJ095950.99+021219.1 has a redshift of 7. Only a handful of galaxies have confirmed redshifts greater than 7, and none of the others is as faint as LAEJ095950.99+021219.1.

“We have used this search to find hundreds of objects at somewhat smaller distances. We have found several hundred galaxies at redshift 4.5, several at redshift 6.5, and now at redshift 7 we have found one,” explains Rhoads. “We’ve pushed the experiment’s design to a redshift of 7 – it’s the most distant we can do with well-established, mature technology, and it’s about the most distant where people have been finding objects successfully up to now.”

Malhotra adds, “With this search, we’ve not only found one of the furthest galaxies known, but also the faintest confirmed at that distance. Up to now, the redshift 7 galaxies we know about are literally the top one percent of galaxies. What we’re doing here is to start examining some of the fainter ones – thing that may better represent the other 99 percent.”

Resolving the details of objects that are far away is challenging, which is why images of distant young galaxies such as this one appear small, faint, and blurry.

“As time goes by, these small blobs which are forming stars, they’ll dance around each other, merge with each other and form bigger and bigger galaxies. Somewhere halfway through the age of the universe they start looking like the galaxies we see today – and not before. Why, how, when, where that happens is a fairly active area of research,” explains Malhotra.

In addition to Hibon, Malhotra, and Rhoads, the paper’s authors include Michael Cooper of the University of California at Irvine, and Benjamin Weiner of the University of Arizona.

Nikki Cassis

marketing and communications director, School of Earth and Space Exploration

Engineering students in final round of international innovation competition

June 1, 2012

About 1,700 teams from throughout the world entered the 2012 Dell Social Innovation Challenge for student entrepreneurs. Now only five of them – including a group of Arizona State University engineering students – remain for the final round of competition June 8-12 at the University of Texas at Austin.

Team 33 Buckets is comprised of mechanical engineering senior Paul Strong and four biomedical engineering students – team leader and senior Pankti Shah, senior Varendra Silva, senior Mark Huerta and junior Connor Wiegand. They will vie for the prizes of $50,000, $20,000 and $10,000, to be awarded to the first-, second- and third-place winners, respectively, at the Dell Challenge finals. 33 Buckets Dell Social Innovation Challenge Download Full Image

The team was formed through the Engineering Projects in Community Service (EPICS) program in ASU’s Ira A. Fulton Schools of Engineering. It was one of eight EPICS teams that were among the 200 teams chosen in the spring as Dell Challenge semifinalists.

System removes arsenic

33 Buckets derives its name from the atomic number of arsenic and the use of buckets in a particular filtration system. Its project is development of a low-cost, efficient and easily maintained filtration system that will remove bacteria and debris – most importantly arsenic  –  from tainted water wells in Bangladesh, where a quarter of the population is exposed to harmful amounts of arsenic, making it a leading cause of death in the country.  

The team’s efforts are focusing first on the Rahima Hoque Girl’s School in the impoverished rural village near Dhaka in Bangladesh. The young students face health risks as the price of their education due to high arsenic concentration in the local water supply.

The filtration system is designed to produce 4,000 gallons of clean drinking water each day, which would leave the school an additional 2,000 gallons to sell to the village to raise funds for improving the school and for replacing the filter components as needed.

The idea for the project came from Enamul Hoque, a native of Bangladesh who earned a master’s degree in civil and environmental engineering from ASU in 1985 and now owns the Hoque & Associates engineering firm in Phoenix. The E.M. Hoque Geotechnical Laboratory at ASU is named for him.

Hoque established and maintains the Rahima Hoque Girl’s School in rural Bangladesh.

Field research in Bangladesh

Hoque accompanied the 33 Buckets team to Bangladesh for eight days in May to do field research for building a prototype of the filtration system and to establish a relationship with the school and the local community.

“I had never been to a Third World country before, so it was a lot to take in,” says team member Huerta.  The team was greeted with warm hospitality and genuine gratitude by the villagers, he says.

The trip included visiting the University of Dhaka to make contacts with students and faculty members who live and work near the area where the team’s project will be implemented. One professor agreed to work with the team to test water samples periodically to ensure the quality and productivity of the filter.

“We were trying to find out if the people were willing to purchase the water, maintain the filter and accept the filter as a solution,” Silva says. They found the school’s students and the villagers are willing to maintain the filtration system, and to sell the extra filtered water at an affordable price for others in the community.

Based on their experience in Bangladesh, the team is making alterations to their project plans in preparation for the Dell Challenge finals competition.

EPICS successes

The director of ASU’s EPICS program has already been recognized by the Dell Challenge organization. Richard Filley recently won an honorable mention in the international 2012 Dell Social Innovation Education Awards.

He is one of only three honorable mention winners – in addition to an overall award winner – selected from among about 100 people who were nominated. The award recognizes dedication to supporting and mentoring students involved in developing innovative solutions to social problems, fostering creativity in classroom teaching methods and dedication to building institutional support for social innovation education.

Under Filley’s direction more 20 students teams working through EPICS have won awards and start-up funding for their entrepreneurial and public service endeavors.

Two other EPICS teams received $1,000 for People’s Choice Awards in the Dell Challenge semifinal round: Project TOTO and FlashFood.

Project TOTO is designing structurally sound tornado shelters out of steel shipping containers. FlashFood is using a mobile-phone application to connect restaurants, catering services and banquet halls that have excess or leftover food  with volunteers who will transport it for distribution to people in need.

Engineering social progress

The Social Innovation Challenge was established in 2007 by the RGK Center for Philanthropy and Community Service in the LBJ School of Public Affairs at The University of Texas at Austin. In 2008, the Dell computer technology corporation joined the program as the title sponsor.
Its mission is to support promising young entrepreneurs who are working to help solve the world’s most challenging social problems.

Over those years, more than 15,000 students from 90 countries have teamed up to enter more than 3,000 projects in the annual competition.

This year 33 Buckets will compete against:

• Team Nanoly – students from Stanford, Duke, the University of California, Berkeley, and the Massachusetts Institute of Technology
• Team Essmart Global – students from the University of Cambridge (England), Tufts University, the Massachusetts Institute of Technology and Harvard
• Team e-Education in 5 Continents – students from the National University of Rwanda, the University of Dhaka (Bangladesh), the University of Jordan and Waseda University (Japan)
• Team Humanure Power Project – students from  Tulane University in Louisiana

Written by Natalie Pierce and Joe Kullman

Joe Kullman

Science writer, Ira A. Fulton Schools of Engineering