A novel is underway: NASA expects to uncover about 100 planets

The Nancy Grace Roman Space Telescope has been successfully launched and is on its way to the L2 Lagrange point. Its outstanding scientific prediction—about 100 transiting planets—is nearly 16 times greater than the 6,354 planets verified so far; however, many of the signals will start out as candidates, and most of the predicted worlds are not Earth twins.

The space telescope Nancy Grace Roman של NASA Successfully launched on Sunday, August 30, 2026, and is now making its way toLagrange point L2, about 1.5 million kilometers from Earth. After the impressive sights of the Falcon Heavy launch and the simultaneous landing of the two side boosters, the really important part begins: transforming the new observatory into a survey machine that will photograph vast expanses of the universe and track hundreds of millions of stars.

The most notable number mentioned in NASA’s launch announcements is the estimated 100 extrasolar planets that Roman could uncover. For comparison, NASA’s planetary archive has 6,354 confirmed planets as of August 20, 2026. In other words, if the prediction comes true, Roman alone could add to a pool nearly 16 times larger than anything astronomers have been able to verify in more than three decades—since the discovery of planets around the pulsar PSR B1257+12 in 1992 and the discovery of 51 Pegasi b around a sun-like star in 1995.

But the comparison requires a scientific asterisk. The 100 prediction is based on simulations of transit signals that a novel might detect, not on a guaranteed list of 100 worlds that would all be confirmed immediately. When a planet transits its star, from our perspective, it slightly dims the star’s light. Such a periodic dip is strong evidence for a planet, but sometimes additional observations or statistical analysis are needed to rule out other sources of the signal. So some discoveries will first fall into the category of candidates.

Not a hundred thousand Earths

The prediction also doesn't mean that Roman will find 100,000 Earth-like worlds. According to estimates published by NASA, about three-quarters of the planets that will be found inThe transition method There are expected to be gas giants or ice giants, such as Jupiter, Saturn, Uranus and Neptune. Many of the others will be mini-Neptunes—planets larger than Earth but smaller than Neptune, a type that does not exist in our solar system.

This bias stems from the nature of the transit method: Large planets that frequently pass in front of their star obscure more light, and are therefore easier to detect. Hot worlds that orbit their stars in short orbits also provide a greater number of transits in a given time. Roman may also find planets in the habitable zone, but the main contribution of the huge sample will be statistical — to understanding what types of planetary systems exist, how they vary from region to region in the Milky Way, and how normal or abnormal our solar system is.

Two methods, two populations of worlds

Roman was not originally designed as a copy of the Kepler mission. The transit discoveries will largely be additional science produced by the same dense, ongoing survey of the center of the Milky Way, which was primarily designed to look for events Tiny gravitational lens.

In a tiny gravitational lens, the gravity of a star or planet in the foreground temporarily bends and magnifies the light of a more distant star. This form of magnification can reveal the presence of a planet even when it or its host star cannot be seen directly. NASA estimates that Roman will find more than a thousand planets using this method.

The two methods complement each other. Transits are particularly sensitive to large worlds close to their stars; tiny lensing can detect smaller worlds in wide orbits, and even Stray planets That are not gravitationally bound to any star. In this way, Roman is supposed to fill in missing areas on the planetary map: not only worlds relatively close to the sun, but populations thousands and even tens of thousands of light years away, towards the bulge of the galaxy's center and up to near its far side.

The importance is not just in numbers. Most of the planets known today are within a few thousand light-years of us. Roman will track hundreds of millions of stars in a dense, ancient galactic environment that is richer in some of the heavy elements from which planets form. Comparing the populations may teach us whether the location of a star system in the Milky Way affects the chances of planets forming there, their size, and the structure of their orbits.

The launch went as planned; the deployment phase has begun.

Roman was launched at 14:26 p.m. Israeli time from Launch Complex 39A at the Kennedy Space Center in Florida. The Goddard Space Flight Center control team received telemetry data about seven minutes after launch, and the telescope separated from the upper stage about 31 minutes after liftoff.

About an hour and 23 minutes after launch, NASA confirmed that the solar panels and lower part of the sunshield had been successfully deployed. The first few days are planned to deploy the main antenna and key cover, activate the coronagraph, and perform the first of two orbit corrections. The Wide Field Instrument, WFI, is expected to be activated a few weeks into the journey.

The journey to L2 and the commissioning and calibration period are expected to last about three months. During this period, the guidance systems, optics, and two science instruments will be tested. NASA estimates that the first images will be released in early 2027, although the schedule depends on the success of the deployments and tests.

Sharpness similar to Hubble, but much wider sky

Roman has a primary mirror 2.4 meters in diameter — the same diameter as the Hubble Space Telescope — but its field of view is at least 100 times wider. The WFI instrument is a 300-million-pixel infrared camera with 18 detectors, each producing a 4K resolution image. According to NASA, Roman’s stable structure and wide field of view will allow it to survey the universe at speeds up to a thousand times faster than Hubble.

The result will be an unprecedented data stream for a NASA astrophysics mission: about 1.4 terabytes per day. Algorithms, machine learning, and citizen scientists are expected to help sift through the vast amounts of images and light curves. The processed data will be open to the research community, so discoveries will not be limited to targets predefined by the mission team.

Alongside WFI is a novel experimental coronagraph, which blocks the bright light of a star to allow imaging of faint objects near it. The coronagraph is not the instrument that will deliver the 100,000 discoveries; its goal is to demonstrate technologies for directly imaging giant Jupiter-like planets. If successful, it will help pave the way for future observatories to attempt to image small, Earth-like worlds near nearby stars.

Much more than a planetary commander

The search for worlds is just one of three main thrusts of the mission. Roman is also designed to study dark energy—the name given to the unexplained factor accelerating the expansion of the universe—and to map dark matter through its gravitational influence on the light and shape of galaxies.

The telescope will measure distant supernovae, map the distribution of galaxies throughout cosmic history, and examine the tiny distortions in their light caused by weak gravitational repulsion. The combination of measurements should allow for a more precise examination of the rate of expansion of the universe and the growth of large structures in it.

The primary mission has been allotted five years of operation, with an engineering goal of reaching ten years. But before any of the predicted discoveries, there are three sensitive months of travel, deployment, operation, and calibration. Only after that will it be clear whether the observatory, which was completed ahead of schedule, can live up to its grand promise: to move from a study of individual worlds to a broad census of planetary populations across the galaxy.

Questions and Answers

Is Roman really expected to discover 100 thousand planets?

This is an estimate based on simulations of planets transiting their stars in the survey field. Some of the signals will require further verification, so it is correct to view the number as a prediction of discovery yield rather than a guaranteed quota of verified worlds.

How many planets outside the solar system are known today?

NASA's Planetary Archive has counted 6,354 confirmed planets as of August 20, 2026. The number is updated as new discoveries are published and reviewed.

Will most discoveries be Earth-like planets?

No. About three-quarters of the worlds found by the transit method are expected to be gas giants or ice giants. Most of the rest are likely to be mini-Neptunes. Tiny gravitational lensing will allow the novel to find smaller worlds in wide orbits as well.

When will the scientific observations begin?

The journey to L2 and the operation of the observatory are expected to take about three months. NASA plans to release the first images in early 2027, subject to the completion of testing and calibration.

How is Roman different from Abel and James Webb?

Roman is not intended to replace them. It combines Hubble-like sharpness with a field of view at least a hundred times wider, making it suitable for rapid surveys of vast areas. Webb specializes in deeper, more detailed observations of selected targets. Title: Roman is on the move: NASA expects to uncover about 100 planets

For the original publication: NASA — Nancy Grace Roman Space Telescope launches

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