NASA Will Send a New Space Telescope Up Soon

CAPE CANAVERAL, FLA. — NASA said Friday that its newest space telescope is ready to fly. The Nancy Grace Roman Space Telescope will launch August 30 on a SpaceX Falcon Heavy rocket from Florida. Roman's mirror is the same size as the Hubble telescope's. But Roman can photograph a piece of sky about 100 times wider in a single shot. That lets it survey huge numbers of stars quickly. Scientists will use it to hunt for planets around other stars. They will also study dark energy, the force that seems to be pushing the universe apart. Nobody knows what it is.

Why it matters: You can watch the launch live on August 30, and the pictures Roman sends back will be free for anyone to look at.

CAPE CANAVERAL, FLA. — Mission managers from NASA and SpaceX completed a Flight Readiness Review at Kennedy Space Center on Friday, certifying the Nancy Grace Roman Space Telescope for final launch preparations. Liftoff is targeted for no earlier than 7:26 a.m. Eastern on Sunday, August 30, aboard a Falcon Heavy from Launch Complex 39A. The observatory, already enclosed in its payload fairing, moves to SpaceX's hangar for mating to the rocket. Roman carries a primary mirror the same 2.4 meters across as Hubble's, but its field of view is about 100 times wider. That single design choice defines the mission. Hubble and Webb are built to stare; Roman is built to survey. It can map large areas of sky repeatedly, which is what you need to detect things that change or to gather statistics across millions of galaxies rather than detailed portraits of a few. The two headline science goals are dark energy and exoplanets. Dark energy is the name given to whatever is causing the universe's expansion to accelerate; naming it is not the same as understanding it, and Roman is designed to measure its behavior over cosmic time rather than explain it. For planets, Roman will use gravitational microlensing, in which a foreground star's gravity briefly magnifies a background star and reveals otherwise invisible companions. The launch is running roughly nine months ahead of the original schedule, which is unusual enough for a flagship observatory to be worth noting on its own.

Background

Roman was recommended by the 2010 astronomy decadal survey, formally started in 2016, and survived several proposed cancellations in budget cycles since. Its wide-field instrument reuses a 2.4-meter mirror donated to NASA by the National Reconnaissance Office, which is part of why the optics were comparatively inexpensive.

Why it matters: Survey instruments rarely produce a single famous image, so they are easy to undervalue. They tend to produce the datasets that other people's discoveries come out of for the next twenty years.

What to watch: The August 30 launch window itself, and then roughly three months of commissioning before the first science data.