SPHEREx Space Telescope Begins Capturing Entire Sky
by NASA
Launched on March 11, NASA's SPHEREx space observatory has undergone checkouts, calibrations, and other preparatory activities over the past six weeks. The observatory is now ready to map the entire sky—not just a portion—to chart hundreds of millions of galaxies in three-dimensional (3D) space.
Scientific Objectives
With the start of regular science operations on May 1, SPHEREx aims to capture approximately 3,600 images per day over the next two years. These images will provide critical insights into the origins of the universe, the formation of galaxies, and the chemical ingredients necessary for life within the Milky Way.
“Thanks to the hard work of teams across NASA, industry, and academia that built this mission, SPHEREx is operating just as we'd expected and will produce maps of the full sky unlike any we've had before,” stated Shawn Domagal-Goldman, acting director of the Astrophysics Division at NASA Headquarters in Washington.
The SPHEREx observatory adds to the suite of space-based astrophysics surveys leading to the launch of NASA's Nancy Grace Roman Space Telescope. Together, these missions will address fundamental questions regarding the universe's structure, origin, and evolution.
Mission Mechanics
Operated from its location in Earth orbit, SPHEREx orbits Earth in a north-south trajectory, making more than 11,000 orbits during its 25 months of survey operations. With a pace of around 14.5 orbits per day, the observatory takes images along a circular strip of the sky daily. As Earth moves around the sun, the field of view for SPHEREx shifts, ensuring that it will ultimately view all sections of the sky after six months of operation.
Data Collection and Analysis
When capturing images of the cosmos, SPHEREx utilizes six detectors, each designed to produce a unique image for different wavelengths of infrared light. An "exposure" consists of six images, and the observatory is capable of taking approximately 600 exposures each day. Post-exposure, SPHEREx shifts its entire position—this is achieved without using thrusters, relying on a series of internal reaction wheels to maintain its orientation.
Mapping the Universe's History
The ultimate goal is to weave together hundreds of thousands of SPHEREx images to create four comprehensive maps of the entire sky over two years. By assimilating data from the entire sky, the mission is set to uncover insights regarding cosmic inflation, which in the earliest moments of the universe, expanded it exponentially.
Using Spectroscopy
SPHEREx won't just provide raw images; it leverages spectroscopy, analyzing 102 wavelengths of infrared light to extract vital information about galaxies and other celestial objects.
| Wavelength (microns) | Scientific Application |
|---|---|
| 0.7 | Near-infrared imaging of stellar populations |
| 1.2 | Detecting organic molecules |
| 2.2 | Studying formation of new stars |
| 3.0 | Examining water's role in star formation |
| 3.6 | Mapping galaxies and measuring cosmic expansion |
The Search for Life
SPHEREx is particularly focused on finding key ingredients for life, such as water and organic compounds present in interstellar clouds. It has been posited that Earth’s oceans were formed from frozen molecules of water carried on dust in the interstellar medium where our sun first formed.
“Some of us have been working toward this goal for 12 years,” stated Jamie Bock, the mission’s principal investigator at Caltech and JPL. “The performance of the instrument is as good as we hoped. That means we're going to be able to do all the amazing science we planned on and perhaps even get some unexpected discoveries.”
Modern Cosmology
The study of cosmic inflation offers unique insights into the early universe, as it provides a roadmap to understanding the current arrangement of matter exemplified by the positions of galaxies. Through aforementioned evidence, scientists can postulate how fundamental forces played a role in the universe's evolution.
| Cosmic Event | Impact on Universe |
|---|---|
| Cosmic Inflation | Expansion of universe from a subatomic origin |
| Galaxy Formation | Structure of matter leading to varied cosmic densities |
| Stars and Planets Lineage | Legacy trace of elements formed in stars |
Conclusion
NASA's SPHEREx mission represents a significant leap forward in our understanding of the cosmos. By mapping the entire sky through a multitude of wavelengths, it will provide valuable data to aid in answering crucial questions regarding the origins of our universe and the chemical foundations that support life as we know it.
For Further Information
As the mission unfolds, more discoveries are anticipated that will enrich our understanding of the universe at large.
