PLANETARY TRANSITS AND OSCILLATIONS OF STARS (PLATO)
Expected launch date: 2026
PLATO will seek out and investigate Earth-size exoplanets, especially planets that orbit in the habitable zone around sun-like stars. (The habitable zone is usually defined as the area around a star where there is enough energy for liquid water on a planet’s surface, although habitability also depends on other factors such as star variability.)
This European Space Agency project will scour a million stars looking for blips in their light that betray the presence of an orbiting planet. Similar kinds of previous telescopes have only been able to see planets that are close to their stars and so pass in front of them frequently. Plato will linger on each star for longer and so has the chance to detect planets that are more distant from their star, with a longer orbital period.
PLATO has 24 normal cameras on board, arranged in four groups of six. Each of these groups has the same field of view, ESA said, but they are offset by a 9.2-degree-angle from the vertical axis of the spacecraft. Additionally, the spacecraft will have two “fast” cameras that will be used for brighter stars.
It will determine how big their radii are; verify the mass of the planets from ground-based observatories; use astroseismology or “starquakes” to learn about a star’s mass, radius and age; and identify bright targets for atmospheric spectroscopy along with other telescopes.
PLATO’s primary mission is expected to last four years. However, the telescope is designed to last 6.5 years and its consumables, such as fuel, are expected to last about eight years. This means that the telescope could continue operations if its science mission was extended.
The spacecraft will be launched from Earth on a Soyuz-Fregat rocket bound for a location called a Lagrange point. A Lagrange point is a relatively stable gravitational zone in space. PLATO will specifically be targeted for the L2 Lagrange point, a spot in space on the “dark” side of the Earth (meaning that the sun is always in the opposite direction.)
L2 has been used before for the Wilkinson Microwave Anisotropy Probe (WMAP) and Planck spacecraft, and is also the region where the James Webb Space Telescope will operate. Since L2 is relatively unstable, the spacecraft will follow a Lissajous orbit, which is a path around the Lagrange point, and periodically use fuel to stay in a consistent orbit.
NANCY GRACE ROMAN SPACE TELESCOPE
Expected launch date: 2025
The Roman Space Telescope, named after the first female executive at NASA, will observe mainly infrared radiation.
“It is fitting that as we celebrate the 100th anniversary of women’s suffrage, NASA has announced the name of their new Wide Field Infrared Space Telescope (WFIRST) in honor of Dr. Nancy Roman, the Mother of Hubble — well deserved,” says former Maryland senator Barbara Mikulski. “It recognizes the incredible achievements of women in science and moves us even closer to no more hidden figures and no more hidden galaxies.”
“It is because of Nancy Grace Roman’s leadership and vision that NASA became a pioneer in astrophysics and launched Hubble, the world’s most powerful and productive space telescope,” says NASA administrator Jim Bridenstine.
Expected to launch in 2027, the telescope will survey millions of galaxies, building a map of our cosmological neighborhood. Astronomers hope to use the distribution of galaxies to tease out the evolution of dark energy. As a bonus, the instrument will also use gravitational microlensing — tiny changes in background starlight — to discover potentially millions of exoplanets.
The telescope has a panoramic field of view more than 100 times greater than the JWST’s. During its first five years, Roman will image more than 50 times as much sky as the Hubble Space Telescope covered in its first 30 years. That will allow it to make the first wide-field infrared maps of the sky. It is hoped this will help solve mysteries like the true identity of dark matter and dark energy.
LASER INTERFEROMETER SPACE ANTENNA (LISA)
Expected launch date: 2034
LISA, a mission led by the European Space Agency, will be a much larger gravitational wave detector than existing ground-based ones. It will consist of three spacecraft positioned 2.5 million kilometres apart in a triangular formation. This space detector will be sensitive to gravitational waves with extremely low frequencies. Among other things, it could allow us to spot planets in other galaxies just from the subtle way in which they influence the gravitational waves produced by their parent stars.
The Laser Interferometer Space Antenna (LISA) is a space-based gravitational wave observatory. Led by the European Space Agency, it will target gravitational wave sources that ground-based detectors can’t, like colliding supermassive black holes and the mergers of compact objects within our own galaxy. LISA is a formation of three satellites, all orbiting the sun together while maintaining a separation of about 1.5 miles (2.5 million km).
By continually bouncing lasers between them, the satellites can measure any slight changes to their distance, especially if gravitational waves come washing through. The observatory is targeted for launch in 2034.