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09/28/22: Public Evening Lecture - The Webb Telescope: Starting Steward Observatory's Next 100 Years

Date: 
Wednesday, September 28, 2022 - 7:30pm to 8:30pm
Room: 
 
Dr. Marcia Rieke, Regents Professor
 
Dr. Elizabeth Roemer, Endowed Chair, Steward Observatory

09/19/22: Public Evening Lecture- 100 Years of Steward Observatory

Date: 
Monday, September 19, 2022 - 6:30pm to 7:30pm
Room: 

Dr. Thomas Fleming

Dr. Buell Jannuzi, Director of Steward Observatory

Steward Postdoctoral Research Associate Michael Jones and Associate Professor David Sand have identified five instances of a new type of stellar system. You can see three images HERE and HERE and HERE. They are around a million times less massive than our galaxy, likely containing only 10,000 to 100,000 stars, which are arranged in a clumpy and irregular configuration. These systems, colloquially referred to as "blue blobs", are dominated by young, blue stars, yet are surprisingly isolated, typically over 300,000 lightyears from the nearest plausible parent galaxy. Furthermore, all five reside in the nearby Virgo galaxy cluster (approximately 50 million lightyears away). Galaxy clusters are filled with hot ionized gas at millions of degrees, making them an extremely hostile environment for the cold gas that is needed to form new stars. Even relatively large galaxies, similar in mass to our own Milky Way, rapidly lose their cold gas content after falling into a galaxy cluster. Yet these tiny "blue blobs" are floating alone, embedded in this hostile, hot medium, and are actively forming new stars. This raises the questions, where did they come from and how did they manage to become isolated while still so young.

To answer these questions Dr. Jones,  Prof. Sand and Professor Kristine Spekkens (RMC, Kingston, Ontario) obtained Hubble Space Telescope and Very Large Array imaging of these systems, as well as observations with the Very Large Telescope in Chile, in collaboration with Dr. Michele Bellazzini (INAF, Bologna, Italy). These observations indicated that the "blue blobs" are rich in heavy elements, which is strong evidence that they formed from gas stripped from a large galaxy that had accumulated these elements as it built up its stellar mass over a long history. Material can be stripped from galaxies in two main ways, tidal stripping and ram pressure stripping. Tidal stripping occurs when two galaxies pass close by each other (or even merge) and their gravity pulls apart their outskirts, resulting in long tails of stripped material. Ram pressure stripping occurs when a galaxy moves rapidly through a gas medium, which forces its own gas out behind it. In either scenario, stripped gas clouds can collapse and form new stellar systems, analogous to "blue blobs." However, ram pressure stripping when galaxies fall into a cluster can occur at very high velocity (higher than can be achieved with tidal stripping) and this offers an explanation for how such young objects can be so isolated; they are just moving at very high speeds, perhaps over 500 miles per second.

These results were presented on Wednesday June 15th at a AAS 240 press briefing, and an accompanying UA press release. Check these out for more details.

Left: Southern Ring planetary nebula images (Right taken by NIRCAM / Left taken by MIRI) Right: Stephan's Quintet galaxies image taken by MIRI

Webb Telescope's stunning first images made possible by UArizona instruments and expertise

After decades of development, a nail-biting launch and months of space travel and commissioning, NASA has released the first scientific images and spectroscopic data captured by the James Webb Space Telescope. The images hint at the beginning of years of space science, which will in part be made possible by the 21 University of Arizona researchers who have played a role in developing and managing the instruments onboard.

The release of Webb's first images and spectra kicks off the beginning of Webb's science operations, in which astronomers around the world will have their chance to observe anything from objects in our solar system to the early universe, using Webb's four instruments. These include the Near Infrared Camera, or NIRCam, which serves as the telescope's short wavelength imager and is led by principal investigator and UArizona Regents Professor of Astronomy Marcia Rieke. George Rieke, Marcia's husband and also a Regents Professor of Astronomy at UArizona's Steward Observatory, serves as science team lead for the Mid-Infrared Instrument, or MIRI, which will observe the universe at longer wavelengths.
 
NIRCam and MIRI played a role in creating several of the images released. Since these instruments and the others onboard operate to detect different wavelengths of light, the images can be stacked or compared to learn more about the composition or structure of their targets. 
 
Webb's first observations tell the story of the hidden universe through every phase of cosmic history – from neighboring exoplanets to the most distant observable galaxies in the early universe, and everything in between. 
 
"Today, we present humanity with a groundbreaking new view of the cosmos from the James Webb Space Telescope – a view the world has never seen before," said NASA Administrator Bill Nelson. "These images, including the deepest view of our universe that has ever been taken, show us how Webb will help to uncover the answers to questions we don't even yet know to ask; questions that will help us better understand our universe and humanity's place within it."
 
The release of the images and spectra reveal the range of capabilities of all four of Webb's state-of-the-art scientific instruments and confirm that future observations will revolutionize our understanding of the cosmos and our own origins.
 
"Each of Webb's four instruments have capabilities that are aimed at particular science investigations," Marcia Rieke said. "Our NIRCam, for example, was designed to survey large swaths of sky using different filters, while MIRI collects light at longer wavelengths than all other instruments onboard. The Canadian instrument, the Near-Infrared Imager and Slitless Spectrograph, or NIRISS, has special mode for detecting the composition of planets that orbit other stars, and the Near Infrared Spectrograph NIRSpec can take spectra of many objects at once."
 
The images are all aesthetically appealing, but they also have scientific utility, Marcia Rieke said. These and future images will be mined for answers to particular science questions.
 
"After years of development and months of commissioning, it's regular operations from here on out," she said.
 
Marcia Rieke said the questions she's most excited to investigate include how the first galaxies came together to create something like our own Milky Way and if we can find an exoplanet with an Earthlike atmosphere.
 
George Rieke said some of the objects he's most excited to study with the powerful MIRI instrument are quasars, which are supermassive black holes at the center of galaxies that create bright jets of light as they consume the surrounding gas.
 
"MIRI and all of Webb's other instruments are ushering humanity into new scientific territory and that's super exciting," he said.
 
Webb's first observations were selected by a group of representatives from NASA, the European Space Agency, Canadian Space Agency and the Space Telescope Science Institute, who are all partners on the project:
 
  • Carina Nebula: Looking at this star-forming region and others like it, with Webb, scientists can see newly forming stars and study the gas and dust that made them.
  • Southern Ring planetary nebula: From birth to magnificent death as a planetary nebula, Webb can explore the expelling shells of dust and gas of aging stars that may one day become a new star or planet.
  • Stephan's Quintet galaxies: Stars derive from, and contribute to, gas and dust in mass quantities, swirling around galaxies. Webb can study nearby and dynamic interacting galaxies to see the gas and dust in action. Now, scientists can get a rare look, in unprecedented detail, at how interacting galaxies are triggering star formation in each other and how the gas in these galaxies is being disturbed.
  • SMACS 0723 deep field view: To truly understand our beginnings, we must trace these galaxies back to the beginning. This deep field uses a lensing galaxy cluster to find some of the most distant galaxies ever detected. This image is only scratching the surface of Webb's capabilities in studying deep fields.
  • WASP-96b exoplanet: Studying other planetary systems like this will help astronomers find out how typical, or atypical, our solar system is. Webb has detected water molecules on an exoplanet and will now set out to study hundreds of other systems to understand what other planetary atmospheres are made of.

"I'm very happy for all the young scientists who staked their early careers on Webb working smoothly and poured their hearts into getting every aspect tested and documented, and then turned it over to the astronomical community to let everyone help rewrite all the textbooks with new discoveries," George Rieke said.

The James Webb Space Telescope launched Dec. 25, 2021, on an Ariane 5 rocket from Europe's Spaceport in French Guiana. After completing the most complex and difficult deployment sequence in space, Webb underwent months of commissioning, in which its mirrors were painstakingly aligned, and its instruments were calibrated to its space environment and prepared for science.
 
NASA Headquarters oversees the mission for the agency's Science Mission Directorate. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages Webb for the agency and oversees work on the mission performed by the Space Telescope Science Institute, Northrop Grumman and other mission partners. In addition to Goddard, several NASA centers contributed to the project, including the agency's Johnson Space Center in Houston, Jet Propulsion Laboratory in Southern California, Marshall Space Flight Center in Huntsville, Alabama, Ames Research Center in California's Silicon Valley and others.
 

This article was written by Mikayla Mace Kelly of UANews.

UA Astronomy and Planetary Science Professor Daniel Apai and Research Associate Martin Schlecker are working on a novel, scalable solution to remove carbon dioxide from the atmosphere to help mitigate the worst impacts of climate change. The project idea was inspired by Apai’s astrobiology research on habitable exoplanets and long-term climate feedbacks that may stabilize the surface temperatures of those worlds. Their team is using a special type of microalgae to capture carbon dioxide. These microalgae use energy from photosynthesis to extract carbon dissolved in the ocean to build shells made of calcium carbonate, a highly stable mineral. As the algae can divide several times a day, they offer a highly scalable, natural solution for large-scale atmospheric carbon dioxide removal. 

 

The University of Arizona press release can be found HERE.

 

Left to right: Michael Lesser, Jianwei Lyu, Tau Herculids meteor shower courtesy of Jianwei Lyu.

Summer News: An Award and an APOD

We recently learned that Dr Mike Lesser, Director of the Imaging Technology Laboratory of Steward Observatory, has won the 2022 Joesph Weber Award of the AAS. Dr Lesser is cited for “innovative and foundational work on methods of thinning, coating, and reading out large-format back-side illuminated CCD detectors. This work has led to significant improvements in performance, and the methods are used by virtually all CCD detectors in astronomical instruments working from optical through X-ray wavelengths.”

You can read more about the award HERE.

While observing at the Steward Bok Telescope on Kitt Peak, postdoc Jianwei Lyu took this composite photo of May 30th's Tau Herculids meteor shower. You can see the photo HERE. Jianwei provides a bit of a backstory: "This is the composite image from 22 single exposures with meteors from 9:00 pm to 11:30 pm (MST time) on May 30. There are 22 meteors in total, and 19 of them shall belong to Tau Herculids. The source of this shower is Comet 73P/Schwassmann-Wachmann 3... The dome in the front is the Steward Observatory Bok 2.3 meter telescope and the one behind it is the 4-meter Mayall Telescope. The reddish color is the reflected light from my headlamp. These photos were taken in front of the dormitory for the Bok observer. I used a Sony A7S camera with ISO 10000 and an exposure time 13 seconds for each exposure. The camera lens is Rokinon 8mm fish-eye. I used GIMP to manually rotate and align all the images, and used one picture as the background, and masked out everything besides the meteors. Then some simple color-balance correction is applied. I am currently a postdoc in the JWST MIRI team at Steward Observatory, University of Arizona. I'm using Bok for my observing run (for quasar studies) and learned about this meteor shower just one day before the event. To make this picture possible, I had driven back and forth for 2+ hours from the Kitt Peak to Tucson to get a battery to power my dead camera controller."

Since May 1, 2022, three Astronomy grad students have received Doctorates: Katrina Litke Marslender on May 3, Ryan Endsley on May 18, and Minghao Yue on May 19. 

Photos can be seen HERE, HERE, and HERE. Congratulations to all of you, we are proud of you.

Also, in May, 2022, Hector Rico of the Department Office received  his Master's degree in Public Health with an emphasis in Health Services Administration. A photo of a celebration in the Dept. Office can be seen HERE.

 

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