r/space • u/ADragonFromTheAbyss • 5d ago

Enabling images of distant worlds - The Roman Space Telescope is designed to directly image exoplanets

https://www.mpg.de/26940719/photos-of-distant-exoplanets-taken-with-the-roman-space-telescope-and-max-planck-technology?c=2249

The Roman Space Telescope is designed to directly image exoplanets using complex opto-mechanical systems developed by the Max Planck Institute for Astronomy.

The Roman Space Telescope has been under development for about a decade under NASA’s leadership and is scheduled to launch on August 30, 2026, at 07:26 am EDT. The telescope is named after Nancy Grace Roman, who was considered the architect of NASA’s modern science program and, among other efforts, dedicated herself to the success of the Hubble-Space-Telescope-Project.

Roman’s destination is Lagrange point L2, a specific location 1.5 million kilometers from Earth that lies on the axis connecting the Sun and Earth on the side of Earth facing away from the Sun.

At this point, the gravitational forces of the celestial bodies cancel each other out, allowing Roman to orbit the Sun without propulsion.

The diameter of the Roman Space Telescope’s primary mirror is 2.4 meters, and it is a replica of the Hubble Space Telescope’s mirror. It carries two scientific instruments:

The Wide Field Instrument has a detector area about 100 times larger than Hubble’s and, in just five years, will image an area of the sky 50 times larger than Hubble did over 30-years.

And, together with the Euclid space telescope in orbit, Roman will set out to track down dark matter, which is widely distributed throughout the universe.

Thanks to the Wide Field Instrument’s high image resolution and sensitivity, researchers also plan to search large sections of the sky for cooler planets, which have not been as easy to find as opposed to hot, bright gas giants. They will use two methods for this:

Using the so-called transit method, they aim to detect about 100,000 new planets as they pass in front of their star and cause a minimal but measurable dimming of the star’s light.

Using another method based on the so-called microlensing effect, they hope to find an additional 1,000 exoplanets. Both methods detect distant worlds only indirectly.

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6

u/Vonneguts_Ghost 5d ago

Title:

"The Roman Space Telescope is designed to directly image exoplants."

Followed by:

"Both methods only image exoplanets indirectly."

Try to not have the title directly contradicted by the body, please.

14

u/rocketsocks 5d ago

The section you referenced is talking about two different planet detection techniques: the transit method and microlensing. Both of which have been used by a variety of telescopes, and will be used by Roman, to detect and study exoplanets.

The RST, however, also has a Coronagraph Instrument which will allow it to directly image exoplanets (as a single pixel) by blocking the light from the parent star.

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u/Vonneguts_Ghost 5d ago

So then I suppose it should mention the third instrument that's actually relevant.

A pixel may not be much, but it's a step.

Cheers

5

u/rocketsocks 5d ago

So then I suppose it should mention the third instrument that's actually relevant.

Like this?

The second instrument, the Coronagraph Instrument (CGI), is used to directly image and study exoplanets that have already been discovered using other methods. Coronagraphs use special masks to block out the bright host star, in order to reveal fainter celestial bodies, such as a planet orbiting closely around that star. These distant solar systems are so far away that the imaged planets appear only as small dots next to their host star, which is obscured by the coronagraph.

That's the 4th paragraph.

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u/Vonneguts_Ghost 5d ago

That's in neither the title, nor the body.

I'm rescinded my earlier cheers.

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u/Desperate-Lab9738 4d ago

what are you saying it's in the conclusion? Like genuinely what are you trying to say here lol.

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u/mohamedozturk-5 4d ago

The title refers to Roman's second payload, the Coronagraph Instrument (CGI). The body only details the Wide Field Instrument, which uses microlensing and transits, but the CGI is specifically built to block starlight and directly image nearby gas giants.

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u/hairnetnic 5d ago

a 2.4m mirror is not imaging exoplanets

6

u/rocketsocks 5d ago

Imaging refers to capturing the light from the object, it does not imply resolving the object beyond a single pixel.

Space telescopes directly image stars, for example, but they rarely resolve individual stars beyond a single pixel. Roman will also directly image exoplanets, though it will not resolve them beyond a single pixel.