NASA Clears Roman Space Telescope for Sunday Launch

NASA and SpaceX teams completed a launch readiness review at Kennedy Space Center in Florida on Friday, August 28, and issued a “go” status, the last check before the countdown begins. That confirms the Nancy Grace Roman Space Telescope will lift off Sunday, August 30, at 7:26 a.m. Eastern time, or 1:26 p.m. Central European Summer Time. The rocket is a SpaceX Falcon Heavy, launching from Kennedy’s Pad 39A, and the U.S. Space Force’s 45th Weather Squadron puts the odds of favorable conditions at 60 percent. If weather blocks a Sunday launch, the backup slot is Monday, August 31, with liftoff four minutes earlier, at 7:22 a.m. Eastern. NASA’s broadcast begins at 6:20 a.m. Eastern, or 12:20 p.m. CEST.

Roman is headed to the same destination as the Webb telescope, Lagrange Point L2, roughly 1.5 million kilometers from Earth. Their jobs differ: Webb studies individual objects with sharp detail and a narrow field of view, while Roman is built for wide sky surveys. Its main instrument, a 300-megapixel camera, matches the Hubble Space Telescope’s resolution but with a field of view 100 times wider. A second instrument, a coronagraph, blocks a star’s light so a planet or other object right next to it can be seen. Roman’s 2.4-meter primary mirror is also the same size as Hubble’s.

The telescope is set to separate from the rocket’s upper stage 31 minutes and 31 seconds after liftoff, when its solar panels and sunshield deploy. The observatory weighs about 18,000 pounds and, once unfolded, measures roughly 12.8 meters. The mission’s total cost is $4.3 billion. Instrument calibration takes about three months, and NASA expects the first science images by January 2027. The primary mission is planned for five years, with an option to extend for another five. According to figures cited by ABC, the telescope is expected to send back about 1.4 terabytes of data daily, more than 500 terabytes a year. Besides ground stations in the United States, the data is also received by a European Space Agency antenna in New Norcia, Western Australia, about 130 kilometers northeast of Perth, operated by the Australian agency CSIRO.

Over its five-year survey, the mission aims to discover about 100,000 exoplanets through the transit method and roughly 1,000 more via gravitational microlensing, while imaging about two billion galaxies. By comparison, Hubble has observed only about 0.1 percent of the night sky over more than 30 years of operation. Shawn Domagal-Goldman, director of NASA’s Astrophysics Division, said ahead of the launch that the telescope “will do things that are currently impossible.” Julie McEnery, a scientist on the Roman mission, told NPR it’s “very likely that we’ll show our standard model is wrong,” referring to the standard model of cosmology that describes dark matter and dark energy.

The telescope is named after Nancy Grace Roman (1925-2018), NASA’s first chief of astronomy and the first woman to hold a leadership position at the agency. She was also known as the mother of Hubble, having lobbied Congress for decades before that telescope’s launch in April 1990 to get the project approved. This is the sixth primary NASA mission that SpaceX has launched on a Falcon rocket from Kennedy Space Center, following IXPE, Psyche, GOES-U, Europa Clipper and IMAP.

The results, though, will take patience. A “go” status means the rocket, telescope, weather and support teams are ready for the countdown, not that liftoff is certain: the chance of favorable weather is put at 60 percent, which is exactly why a backup slot exists. And a successful launch by itself proves nothing about dark matter or dark energy. The instruments will be activated and tested over the following months, the first photos and the start of science operations aren’t expected until January 2027, and McEnery was speaking about a possibility, not a confirmed result: that Roman will “very likely show” the existing standard model of cosmology is wrong, not that it already has.