How Does The Hubble Telescope work?

 

The **Hubble Space Telescope** is a large, space-based observatory that orbits the Earth and captures images and data of distant astronomical objects. It operates primarily in visible, ultraviolet, and near-infrared light. Here's how it works:

### 1. **Location: Space Orbit**

The Hubble Space Telescope orbits approximately 547 kilometers (340 miles) above Earth, positioned beyond the planet's atmosphere. This positioning allows it to avoid atmospheric distortions (like turbulence) that affect ground-based telescopes.

### 2. **Optical Design: Cassegrain Reflector**

   - Hubble uses a type of telescope known as a **Cassegrain reflector**, which has two main mirrors:

     - **Primary mirror** (2.4 meters or 7.9 feet in diameter): Light from distant stars, galaxies, or other objects enters the telescope and strikes the primary mirror.

     - **Secondary mirror**: The primary mirror focuses the light onto a smaller secondary mirror, which reflects the light back through a hole in the center of the primary mirror toward its scientific instruments.

   

### 3. **Scientific Instruments**

   Hubble has several instruments designed to capture light in various wavelengths:

   - **Wide Field Camera**: Captures detailed images of celestial objects in visible and near-infrared light.

   - **Spectrographs**: Analyze the composition of objects by splitting their light into its constituent wavelengths, helping scientists determine the object's temperature, composition, velocity, and more.

   - **Infrared and Ultraviolet Detectors**: Collect light in wavelengths that are invisible to human eyes, revealing objects hidden in dust clouds or processes that happen at different energies.

### 4. **Power: Solar Panels**

   - Hubble is powered by two large solar panels that convert sunlight into electricity, which charges its batteries. The solar energy powers all of Hubble's instruments, computers, and communication systems.

### 5. **Pointing and Stabilization**

   - **Gyroscopes** and **reaction wheels** help keep Hubble precisely pointed at its target. Fine-tuned stabilization is critical because any wobble would blur the images.

### 6. **Data Collection and Transmission**

   - Hubble's cameras and spectrographs gather light and convert it into digital data. This data is sent to Earth via a relay system of satellites called the **Tracking and Data Relay Satellites (TDRS)**.

   - Once received, the data is processed and analyzed by scientists at ground control centers, including the Space Telescope Science Institute (STScI).

### 7. **Imaging and Research**

   - The telescope provides high-resolution images of galaxies, nebulae, black holes, stars, and planets, allowing astronomers to make discoveries about the universe's structure, age, and development.

   - Since its launch in 1990, Hubble has provided revolutionary insights, such as determining the rate of the universe's expansion and capturing the first direct image of a planet outside our solar system.

Hubble’s design allows for long-term use, with periodic upgrades and servicing missions (by astronauts) to keep it functional for decades.