Groundbreaking Rubin Observatory's Giant Camera Poised to Reshape Cosmic Understanding

Perched atop a mountain in Chile, a dedicated team of scientists and engineers is on the cusp of launching an astronomical mission of unprecedented scale. Among them is Kshitija Kelkar, whose journey into astronomy began with a simple photograph.

Two decades ago, Kelkar, then in Pune, India, captured a lunar eclipse with her digital camera and submitted it to Sky and Telescope magazine. The publication featured her photo as its "Photo of the Week," igniting a passion that would shape her career.

Inspired by this early success, Kelkar pursued astronomy, earning degrees from Fergusson College, Pune University, and the University of Nottingham. Her doctoral research focused on the transformation of galaxies within clusters, leading her to Chile on a grant to utilize telescopes for her investigations.

Today, Kelkar serves as an observing specialist at the Vera C. Rubin Observatory, where she now observes the cosmos through the lens of the largest digital camera ever constructed.

On June 23, the Rubin Observatory unveiled a series of breathtaking images, showcasing galaxy clusters, distant stars, and nebulae in remarkable detail. One particular image captured a nebula approximately 4,000 light-years away, utilizing the camera's impressive 3.2-gigapixel resolution and car-sized dimensions.

The Rubin Observatory even holds the potential to safeguard Earth. In May, it detected 2,104 previously unknown asteroids within a mere 10-hour timeframe. The telescope's rapid image capture allows it to identify moving objects against the backdrop of stationary stars. This capability is crucial for detecting and tracking potential space rocks that may pose a threat to our planet.

While other powerful telescopes exist, such as the James Webb Space Telescope located 1.5 million kilometers from Earth, and its predecessor, the Hubble Space Telescope orbiting 500 kilometers above Earth, the Rubin Observatory offers a unique advantage. In 1995, Hubble required nearly a week of long exposure to produce the iconic Hubble Deep Field image, revealing approximately 3,000 distant galaxies.

During its initial test run in April, the Rubin Observatory generated an image showcasing 10 million galaxies in mere hours.

The Rubin Observatory's mission distinguishes it from other telescopes. Unlike James Webb and Hubble, which focus on specific targets, Rubin is a survey telescope designed to capture the entire expanse of the sky. Each image covers an area equivalent to 40 full moons, while Webb's cameras capture a region smaller than a full moon. A single photograph from Rubin is so immense that it would require 400 ultra-HD TV screens to display it in its entirety.

This expansive view is essential to Rubin's purpose. Its primary optical instrument, the Simonyi Survey Telescope, is poised to commence a 10-year project called the Legacy Survey of Space and Time (LSST), with the goal of mapping the visible sky in unprecedented detail. The telescope, weighing over 300 tonnes, will utilize CO2 for regular cleaning. Over the next decade, the telescope and the giant LSST camera will capture images of the southern hemisphere sky every 3-4 nights, creating the largest time-lapse film of the Universe ever produced.

The time-lapse approach is crucial for identifying changes and interactions within the cosmos. As Kelkar explained, the observatory will continuously capture 30-second images using different filters. By observing the night sky every 30 seconds and taking two back-to-back images of 15 seconds each, the telescope will detect any object that has altered its position or brightness.

These objects may include stars, asteroids, unnamed comets, and even potential sources of gravitational waves. Kelkar emphasized that Earth's telescopes are designed to complement each other, rather than compete.

The data generated by the Rubin Observatory will be invaluable to scientists, amateur astronomers, and space enthusiasts worldwide. Arvind Paranjpye, director of Nehru Planetarium in Mumbai, noted that just as past discoveries challenged the notion of Earth being at the center of the system, the Rubin Observatory may unveil groundbreaking findings, potentially even evidence of extraterrestrial life.

Kelkar has been stationed at Rubin Observatory for over a year, residing in La Serena, a town two hours away. Her commute takes her through picturesque valleys along the "El Camino de las Estrellas," or "Route to the Stars," named for the numerous astronomical observatories along the way.

The route requires careful light management, restricting the use of full-beam headlights after dark. At the observatory, work commences shortly before sunset. Kelkar and other observing specialists conduct system checks before opening Rubin's massive dome for nighttime operations.

The observatory's location atop Cerro Pachón mountain places it above the turbulent layer of air, providing a clear view of the stars.

Currently, trials are underway as crews perform final checks before Rubin Observatory, the result of 20 years of development and $800 million in construction costs, formally begins its survey later in 2025.

The Legacy Survey of Space and Time will be of an unprecedented scale.

The 10 million galaxies revealed in Rubin's released image represent just 0.05% of the nearly 20 billion galaxies the observatory will have imaged by the end of the LSST project in a decade. Rubin Observatory may witness millions of distant stars ending in supernovae and explore new reaches of our own Milky Way galaxy.

The observatory is expected to generate approximately 10 million alerts to scientists every night, triggered by any detected changes in the series of captured photos. Software will automatically compare new images with older ones, detecting objects that have moved, flashed, exploded, or streaked past. These changes will trigger alerts within minutes.

No other telescope possesses the capability to detect real-time changes in the immediate sky and flashes of light from distant objects at such a scale. In just one year, Rubin Observatory will have detected more asteroids than all other telescopes combined.

The Simonyi Survey Telescope, mounted on a special platform, is exceptionally fast, capable of swiveling from one wide area of the sky to another in just five seconds.

Nothing will escape this all-seeing eye. Kelkar stated that experts worldwide have already been notified to investigate the 2,104 newly detected asteroids. She added that the telescope will be a game-changer, providing a common dataset for all kinds of science simultaneously, eliminating the need for specialized observations.

Kelkar was present in the control room in La Serena when the first images arrived.

She reflected on the culmination of 20 years of dedicated work, anticipating the creation of a 10-year movie of the night sky using the fastest telescope and the largest camera ever built. She expressed her excitement, confident that it would be a fantastic endeavor.