Team led by Stony Brook and AMNH researchers announces first discovery in images from new array telescope
A new telescope called the “Condor Array Telescope” could open up a new world of ultra-low-luminosity space for astrophysicists. Four new papers published in succession in the Monthly Notices of the Royal Astronomical Society (MNRAS) this month present the first scientific discoveries based on observations taken by the condor. The project is a collaboration led by scientists from Stony Brook University's Department of Physics and Astronomy and the American Museum of Natural History (AMNH).
According to principal investigator Kenneth M. Lanzetta, a professor in the Department of Physics and Astronomy at Stony Brook University, Stony Brook's Stephen Gromall. Michael M. Shara, curator of AMNH's astrophysics department, said Condor is currently in full operation. The new “array telescope” uses computers to combine light from multiple small telescopes into light equivalent to one large telescope, allowing him to see faint astronomical phenomena that cannot be seen with traditional telescopes. can be detected and studied.
In the first paper, Lanzetta and colleagues used Condor to study an extremely weak “stellar stream” surrounding the nearby galaxy NGC 5907, a famous spiral galaxy about 50 million light-years from Earth. Such flows are produced when a subgalaxy is disturbed by the tidal gravity of the host galaxy. Previous images taken with another telescope in 2010 appeared to show remarkable streams of stars forming two complete loops of a spiral surrounding the galaxy. However, another image obtained by the Dragonfly Telephoto Array in 2019 showed no trace of this spiral.
The Condor team decided to test the new array telescope and consider its discrepancies. They obtained deep images of NGC 5907 in 2022. Similar to the dragonfly image, the condor image showed no trace of a spiral, leading the researchers to conclude that the spiral in the 2010 image was likely an artifact related to image processing. Images of the condor also revealed subtle features not captured in previous images.
In the second paper, Shara and colleagues used Condor to reevaluate images of the dwarf nova Z Camelopardalis, or “Z Cam,” obtained in January 2007 by Kitt Peak National Observatory's 4-meter telescope. The image showed a partial shell of gas surrounding it. Shara speculated that Z Cam was emitted by a “new star” recorded by imperial Chinese astrologers in 77 BC.
To test this speculation, the Condor team acquired new Z-cam images in November 2021. They then measured the rate of expansion of the shell by comparing its position in earlier and later images and discovered that the rate of expansion was indeed correct. It coincides with an explosion over 2000 years ago.
But to their surprise, the researchers discovered that the new condor images revealed a complete shell of gas surrounding the Z-cam, rather than the partial shell shown with the four-meter telescope. In addition, images of the condor revealed another, even larger shell surrounding the first shell.
“These new images show how sensitive Condor is. The new shells are so faint that they can't be seen with traditional telescopes,” Lanzetta says.
“This is the first example of two concentric shells surrounding a dwarf nova ever discovered, and the concentric shells must surround the frequently erupting nova of a relatively massive white dwarf star. “This confirms the long-held hypothesis that there is no such thing,” said Shara, lead author of the Z Cam paper. .
Two other papers describe another very weak shell of gas surrounding another nova. The shell's existence had been predicted, but it was too faint to be detected by conventional telescopes. This nova shell is 50 times larger than any known nova shell and is the result of multiple nova shells colliding over tens of thousands of years. Links to papers 3 and 4 are below.
Lanzetta's research to date has focused on extragalactic astronomy and cosmology, including the formation and evolution of galaxies and the evolution of the intergalactic medium. Gromoll is an expert in large-scale scientific computing. Shara's previous research focused on novae and later stages of stellar evolution.
Lanzetta and Gromol began work on Condor in 2019 with a grant from the National Science Foundation's Advanced Technology and Instrumentation Program. Shara joined the project in 2020. In 2021, the Condor team deployed the instrument to a very dark observatory at the Dark Sky New Mexico Observatory in the southwestern corner of New Mexico, near the town of Animas.
The project team includes faculty and students from Stony Brook University's Department of Physics and Astronomy, the American Museum of Natural History's Department of Astrophysics, and collaborators from around the world.