Discovering More About the Universe with CMB-HD

Taking a Deeper Look Into the Sky

Join us in our exciting journey to uncover more about the universe



One day, we will know how the Universe began,
what is in it, and where it is going.


To further humanity’s understanding of the Universe.
To build a culture of caring, connection, responsibility, and trust within the project team.
To share the excitement of science with the public.

CMB-HD Science

  • Fundamental Physics of the Universe

  • Evolution of Galaxies

  • Solar and Extrasolar Planets

  • Cosmic Explosions

CMB-HD Survey and Instrument

CMB-HD is a proposed millimeter-wave survey over half the sky that would be both ultra-deep (0.5 uk-arcmin) and of high-resolution (15 arcseconds). CMB-HD would be a revolutionary leap beyond current millimeter surveys and would answer many outstanding questions in both fundamental physics of the Universe and astrophysics.


CMB-HD APC White Paper to the Astro2020 Decadal and Snowmass2021

CMB-HD Request for More Information (RFI) from the Astro2020 Decadal

Publications Referring to CMB-HD

CMB-HD News and Updates

Aspen Center for Physics Summer Program: New Discoveries in the Era of High-Resolution, Low-Noise CMB Experiments
September 5-19, 2021

(Deadline for Applications is January 31, 2021.)


The CMB-HD collaboration received a Request for More Information (RFI) from the Astro2020 Decadal on November 14, 2019.

The requested information was submitted to the Astro2020 Decadal on December 9, 2019.


The CMB in HD: The Low-noise
High-resolution Frontier
December 12-14, 2018 at the Computational Center for Astrophysics in the Flatiron Institute

The goal of this workshop was to flesh out the science case of, and the instrumental path towards, an ultra-deep, high-resolution CMB survey over a large fraction of the sky.

The product of this workshop was a science white paper submitted to the Astro2020 Decadal in March of 2019 that outlined the compelling science case that could uniquely be achieved by a CMB-HD survey. Following this, in July 2019, we submitted an APC white paper to the Astro2020 Decadal, which described the CMB-HD project in more detail, including the flow down from science goals to technical requirements, and the instrumentation necessary.

The CMB-HD concept was originated in the summer of 2018.

SF Center for Computational Astrophysics

The CMB-HD Team

The CMB-HD vision and mission is shared by a large and growing international community.

The Unseen Matter

CMB-HD will map all the dark matter in the Universe down to scales smaller than galaxies. It will do so using the gravitational bending of the Cosmic Microwave Background light. This will reveal how galaxies formed and what the dark matter is made of.

CMB-HD will also determine if the Cosmic Microwave Background light carries the imprint of unknown light particles that were interacting with the known particles in the early Universe.

The First Moments of the Universe

CMB-HD will collect the light of the Cosmic Microwave Background to see the
imprints of the first moments of the Universe’s creation.

Evolution of Galaxies and Gas

How do galaxies form and evolve? CMB-HD will map the pressure, density, temperature, and velocity profiles of the gas in and around galaxies to reveal answers to this question.

Planetary Studies

CMB-HD will provide a census of planets and dwarf planets hundreds of AU from the Sun. It will also open a new window on planetary studies by detecting exo-Oort clouds around other stars, and advance the study of debris disks around large stellar populations.

The Variable and Transient Universe

CMB-HD will map the variable Universe by surveying half the sky every day.
Weekly maps will be made public to the astronomy community.

Join Us

The CMB-HD collaboration is open to the entire U.S. science community.
International partners are also welcome.

For inquires or to join, please contact:
Neelima Sehgal (