SPHEREx launch and telescope details

NASA's pursuit of understanding the cosmos is set to take a significant leap forward with the upcoming launch of a new sky-mapping space telescope, the SPHEREx space telescope, which is scheduled to launch on February 27, 2025. The launch will take place from Launch Complex 4E at Vandenberg Space Force Base in California.
This advanced piece of technology promises to revolutionize how we observe and comprehend the universe. As anticipation builds, NASA has announced that they will provide a comprehensive preview of the telescope before its launch.

Image credit: BAE Systems

What does SPHEREx stand for? (Spectro-Photometer for the History of the Universe, Epoch of Reionization! Since you asked :)

What makes SPHEREx so special? 

SPHEREx will scan the entire sky in 96 different infrared wavelengths (between 0.75 and 5 microns), creating a spectral map far more detailed than previous all-sky surveys. Unlike traditional telescopes that capture images in a few specific bands of light, SPHEREx will collect spectra for every pixel, revealing detailed composition and distance information for millions of objects.

Also, one of its main goals is to study the large-scale structure of the universe to investigate cosmic inflation, the rapid expansion that occurred fractions of a second after the Big Bang.

By measuring the redshift of galaxies, SPHEREx will help us understand how the universe expanded over time.

Seven specifics about the SPHEREx launch and telescope

1. Optical system & instrumentation

• Telescope Type: Wide-field catadioptric telescope (uses both mirrors and lenses)
• Aperture: 20 cm (8 inches)
• Field of View (FoV): 3.5° x 7°
• Spectral Resolution:
• R ~ 41 for 0.75–4.1 µm
• R ~ 135 for 4.1–5.0 µm
• Spectral Coverage: 0.75 – 5.0 µm (Near-Infrared & Shortwave Infrared)
• Pixel Scale: 6.2 arcseconds per pixel
   

2. Detectors & imaging

• Detector Type: Four HAWAII-2RG infrared detectors (HgCdTe-based)
• Detector Size: 2048 × 2048 pixels each
• Total Pixels: 16.8 million pixels
• Readout Mode: Non-destructive readout for improved signal-to-noise ratio
   

3. Scanning & observing strategy

• Sky Coverage: 100% of the sky every six months
• Survey Strategy: Uses a step-and-stare method with 2.5-second exposures per field.
• Each location on the sky is observed at least 12 times during the mission.
• Entire sky mapped four times over the mission lifetime.
• Pointing Accuracy: ~1 arcminute RMS
• Attitude Control: 3-axis stabilized | Uses reaction wheels and star trackers for precision.
   

4. Spacecraft & operations

• Bus: Based on Ball Aerospace BCP-100 platform
• Power: ~300 W from solar panels
• Communication: X-band for science data (~100 Gbits per day) | S-band for telemetry and commanding
• Mass: 178 kg (~392 lbs)
• Lifetime: 2-year mission (baseline), with potential for extension
• Orbit: Sun-synchronous polar orbit (~700 km altitude)
   

5. Cooling system

• Cryogenic Cooling: Passively cooled (no cryogenic liquids required)
• Operating Temperature: Detectors cooled to ~80 K (-193°C, -316°F)
• Cooling Mechanism: Uses a passive radiator to maintain low temperatures for infrared sensitivity.
   

6. Launch & deployment

• Launch Vehicle: SpaceX Falcon 9
• Launch Date: Planned for 2025
• Launch Site: Vandenberg Space Force Base, California
• Deployment: Deploys from Falcon 9 into a Sun-synchronous orbit.
   

7. Science goals

SPHEREx will use its infrared spectral mapping capabilities to:

• Investigate cosmic inflation by mapping the large-scale structure of the universe.
• Study the Epoch of Reionization by analyzing distant galaxies.
• Map water and organic molecules in the Milky Way and protoplanetary disks.
   

SPHEREx’s unique combination of all-sky coverage, spectral imaging, and infrared sensitivity will provide an unprecedented dataset for astronomers worldwide.

NASA to preview Sky-Mapping Space Telescope ahead of launch

The upcoming preview is a testament to NASA's commitment to transparency and public engagement. This event will offer scientists, researchers, and space enthusiasts a closer look at the technological marvel that promises to chart the skies with unprecedented precision. The telescope is designed to map the entire sky, potentially uncovering new celestial phenomena and providing invaluable data to enhance our understanding of the universe's structure and origins.

The sky-mapping telescope is equipped with cutting-edge technology, enabling it to capture high-resolution images and vast amounts of data. Its capabilities are expected to surpass those of its predecessors, allowing for more detailed and comprehensive sky surveys. The telescope's design incorporates advanced sensors and imaging systems that will facilitate the discovery of new stars, galaxies, and other cosmic entities. This mission is anticipated to open new avenues of research and exploration for astronomers worldwide.

The data collected by this new telescope will not only enhance our understanding of space but also contribute to various fields of research, including astrophysics and cosmology. The ability to map the sky in such detail will allow scientists to study celestial phenomena like never before, offering insights into the formation and evolution of galaxies, star systems, and potentially even dark matter. This endeavor underscores NASA's role as a leader in space exploration and scientific discovery.

As NASA prepares to preview this groundbreaking sky-mapping space telescope, the anticipation among the scientific community and the public alike continues to grow. This mission represents another significant step in humanity's quest to explore the universe and unlock its many secrets. By providing a detailed look at the telescope before its launch, NASA is ensuring that the world is ready to embrace the discoveries that await us in the vast expanse of space.

View the full press release