# LiteBIRD

> planned Japanese small space observatory

**Wikidata**: [Q57385960](https://www.wikidata.org/wiki/Q57385960)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/LiteBIRD)  
**Source**: https://4ort.xyz/entity/litebird

## Summary
LiteBIRD is a planned Japanese small space observatory designed to study the cosmic microwave background (CMB) radiation from space. Scheduled for launch in 2027, it will operate at the L2 Earth-Sun Lagrangian point to map polarization patterns in the CMB, aiming to detect primordial gravitational waves from the early universe. Led by the Japan Aerospace Exploration Agency (JAXA) and the Institute of Space and Astronautical Science (ISAS), it will test theories of cosmic inflation.

## Key Facts
- **Launch Date**: 2027 (planned)
- **Operators**: Japan Aerospace Exploration Agency (JAXA) and Institute of Space and Astronautical Science (ISAS)
- **Location**: L2 Earth-Sun Lagrangian point
- **Primary Mission**: Measure cosmic microwave background (CMB) polarization to detect primordial gravitational waves
- **Classifications**: Artificial satellite, space telescope, cosmic microwave background experiment
- **Website**: http://litebird.jp
- **Aliases**: ライトバード (Japanese)
- **Institutional Heritage**: ISAS founded in 1955 as a Japanese national research institute

## FAQs
### Q: When will LiteBIRD launch?
A: LiteBIRD is scheduled for launch in 2027, with the rocket launch event marking a key milestone in its mission to study the early universe.

### Q: What is the main goal of LiteBIRD?
A: Its primary objective is to detect primordial gravitational waves through precise measurements of CMB polarization, testing theories of cosmic inflation.

### Q: Where will LiteBIRD operate?
A: The observatory will be stationed at the L2 Earth-Sun Lagrangian point, a gravitationally stable location ideal for long-term space-based observations.

## Why It Matters
LiteBIRD represents a critical effort to probe the earliest moments of the universe, focusing on the first fraction of a second after the Big Bang. By mapping the polarization of the CMB, it aims to detect signatures of primordial gravitational waves—ripples in spacetime predicted by cosmic inflation theory. This mission addresses fundamental questions about the universe’s origins, such as whether inflation occurred and what physical processes governed the cosmos at its birth. Success would confirm or refute major theoretical frameworks, reshaping cosmology and high-energy physics. As a small but highly specialized observatory, LiteBIRD complements larger missions like Planck and Simons Observatory, emphasizing precision over scale to achieve unprecedented sensitivity to CMB polarization.

## Notable For
- **Focus on Primordial Gravitational Waves**: Designed specifically to detect B-mode polarization patterns in the CMB, a smoking gun for cosmic inflation.
- **L2 Earth-Sun Positioning**: Utilizes the thermally stable environment of the L2 Lagrangian point to minimize measurement interference.
- **International Collaboration**: Involves partnerships with global research institutions, despite being a JAXA/ISAS-led project.
- **Advanced Detector Technology**: Employs superconducting transition-edge sensor (TES) bolometers for high-precision polarization measurements.

## Body
### Overview
LiteBIRD is a small space observatory with a mission to study the cosmic microwave background (CMB) radiation, the afterglow of the Big Bang. As a collaborative project led by JAXA and ISAS, it builds on Japan’s legacy of space-based astronomy, including missions like AKARI and Suzaku.

### Mission Objectives
- **Primary Goal**: Detect B-mode polarization in the CMB to identify primordial gravitational waves from cosmic inflation.
- **Scientific Targets**:
  - Measure tensor-to-scalar ratio (r) with a precision of σ(r) < 0.001.
  - Map CMB polarization across 98% of the sky.
  - Characterize Galactic foregrounds and systematic errors.

### Launch and Operations
- **Launch Vehicle**: To be announced; launch window in 2027.
- **Mission Duration**: Baseline 3-year survey, with potential extensions.
- **Orbit**: Halo orbit around L2 Earth-Sun Lagrangian point, maintaining thermal stability and continuous sky visibility.

### Instrumentation
- **Telescope Design**: 50 cm aperture refractor with a wide-field optical system.
- **Detector Array**: 2,624 superconducting TES bolometers cooled to 0.1 K.
- **Frequency Coverage**: 34–448 GHz across 15 bands to separate CMB signals from foreground emissions.

### Legacy
LiteBIRD’s findings will either confirm inflationary cosmology or challenge existing models, guiding future missions like PICO and CMB-S4. Its technological innovations in detector sensitivity and systematics control will benefit next-generation CMB experiments, ensuring its impact extends beyond its operational lifespan.