Satellite swarms are increasingly spoiling Hubble Telescope Images

Subject: Science and technology

Section: Space Technology

Concept :

Research published this week in Nature Astronomy suggests, showing that the Hubble Space Telescope is being impacted by these burgeoning satellite swarms.
The steadily growing satellite population has been posing challenges for ground-based astronomy, but new research reveals that space-based telescopes like Hubble are also suffering.
Constellations such as Starlink and OneWeb greatly exacerbate the issue, producing annoying streaks in astronomical imagery.

About the study

For the study, the researchers looked at more than 100,000 individual Hubble images contributed by over 10,000 citizen scientists working on the Hubble Asteroid Hunter project.
A deep learning algorithm was trained to spot images marred by satellite streaks and ignore similar trail-like features caused by natural phenomena, such as asteroids, gravitational lensing, and cosmic rays.
It is found that 7% of Hubble images taken from 2009 to 2020 were tarnished by satellite streaks. By 2021, this number had risen to 5.9%.
There were 1,562 Starlink and 320 OneWeb satellites in orbit at the time, “increasing the population of satellites close to the orbit” of Hubble.
Data for this analysis stopped in 2021, but it’s now two years later, and with so many more satellites currently working in orbit, the problem is undoubtedly much worse.

Mitigation Efforts

Astronomers are also asking satellite operators to do their part, such as making their satellites less reflective.
In response to such requests, SpaceX has been experimenting with some mitigation techniques for Starlink, such as using dark paint to absorb sunlight.
Unfortunately, this particular “mitigation was less effective than desired,” according to SpaceX.
Other approaches, namely a visor to block reflective sunlight and orientation adjustments to minimize surface area, have proven to be “highly effective,” the company claims.
SpaceX is also experimenting with “dielectric mirror film,” which directs light away from Earth.

Hubble vs Webb Telescope

Hubble is currently operating some 336 miles (540 kilometers) above the surface, which is roughly 6 miles (10 km) lower than some of the highest Starlink satellites.
A solution might be to significantly raise Hubble’s orbit, which has shrunk dramatically over the decades. NASA and SpaceX are currently hatching a plan to determine if such a thing is possible.
As an aside, the recently deployed Webb Space Telescope is immune to satellite streaks, as it’s working 932,000 miles (1.5 million km) away in the second Lagrange point.

Hubble Telescope

The Hubble Space Telescope is known for recording awe-inspiring images of the cosmos.
The Hubble Space Telescope was launched into low Earth orbit in 1990 and remains in operation.
The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA’s Great Observatories, along with the Compton Gamma Ray Observatory (1991–2000), the Chandra X-ray Observatory, and the Spitzer Space Telescope (2003–2020).
Hubble and its four main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum.
Hubble’s orbit outside the distortion of atmosphere of Earth allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes.
It has recorded some of the most detailed visible light images, allowing a deep view into space.
Many Hubble observations have led to breakthroughs in astrophysics, such as determining the rate of expansion of the universe.

Contributions of Hubble Telescope

Helped pin down the age for the universe now known to be 13.8 billion years, roughly three times the age of Earth.
Discovered two moons of Pluto, Nix and Hydra.
Helped determine the rate at which the universe is expanding.
Discovered that nearly every major galaxy is anchored by a black hole at the centre.
Created a 3-D map of dark matter.