NASA’s Next Large Exoplanet Hunting Space Telescope may find more “rogue” planets than there are stars in the Milky Way, according to a new study published last week in The Astronomical Journal.
It is believed that there are between 100 billion and 400 billion stars in the Milky Way.
What are “rogue” planets?
Rogue planets are those that move through space without orbiting a star. Often described as floating, they are isolated bodies that resemble planets, possibly having been ejected from a star system.
However, astronomers don’t know if rogue planets are coming. They might be:
- could form in the gas disks around young stars before being ejected.
- be ejected after overflights of other stars.
- could form on its own in space, as stars form.
They also don’t know how many rogue planets there are in our Milky Way galaxy.
“If we find a lot of low-mass rogue planets, we’ll know that when stars form planets, they’re probably throwing a bunch of other stuff out into the galaxy,” said Samson Johnson, an astronomy graduate student at Ohio. State University and lead author of the study.
“It helps us to better understand the formation path of planets in general.”
Cue NASA’s future Nancy Grace Roman Space Telescope, also known as the The novel– whose launch is scheduled for the mid-2020s.
How many “rogue” planets are there?
It’s unknown, but there could be a huge amount. “Several rogue planets have been discovered, but to get the full picture our best bet is something like Roman,” Johnson said. “It’s a totally new frontier.”
“The Universe could be teeming with rogue planets and we wouldn’t even know it,” said co-author Scott Gaudi, professor of astronomy and distinguished scholar at Ohio State. “We would never know without undertaking an in-depth study of the space microlens as Roman will.”
What is the microlens?
The microlens is one of the Roman’s key skills that will allow him to search for exoplanets much deeper in space than any other space telescope.
It’s a technique that relies on the gravity of stars and planets to bend and magnify the light from stars passing behind them from the telescope’s point of view. However, this effect is only visible briefly every few million years.
This will allow astronomers to find new types of exoplanets they haven’t yet been able to see – including rogue planets – thousands of light years from Earth.
Finding rogue planets in microlens will require incredible sensitivity, but the study’s authors claim the Roman will be 10 times more sensitive to rogue planets than other space telescopes.
That said, it will only be able to find large rogue planets the size of Mars, the authors say.
What is the Roman?
Formerly known as the Wide Field Infrared Survey Telescope (WFIRST) until it was renamed Romain earlier this year, its “Galactic Exoplanet Survey” is designed to find Earth-like exoplanets and help astronomers find their way around. understand how the Universe is developing.
The Roman is named after NASA’s first chief astronomer, also known as the “mother” of the Hubble Telescope.
However, although the Roman is often compared to the Hubble because it will have the same size mirror at 2.4 meters, the Roman’s wide-angle lens will give it 100 times the field of view that will allow it to map the Milky Way and the like. . galaxies 100 times faster than Hubble.
According to NASA, the Roman has an expected development cost of $ 3.2 billion and a maximum cost of $ 3.9 billion.
“It gives us a window into these worlds that we wouldn’t have otherwise,” Johnson said. “Imagine our little rocky planet floating freely in space – that’s what this mission will help us find. ”
I wish you clear skies and wide eyes.