The global hunt for exoplanets has remained focused on finding a planet like Earth that
contains elements of life. The concept of planets beyond our own solar system, or exoplanets, has
captivated the public for decades. And with the advances in technology in recent years, we are now
able to detect and study these distant worlds in ways that were once unimaginable. In this regard,
2022 was a year of extraordinary success, as astronomers from across the globe discovered
over 200 planets beyond our solar system, some of which are poised for further investigation
by the James Webb Space Telescope and others. Since the beginning of the planetary survey
outside our Solar System, the exoplanet database contained less than 5,000 planets when the year
began. In this video, let’s take a look back at the most exciting exoplanet discoveries of 2022.
In a recent tweet, NASA stated, "We started the year with fewer than 5,000 confirmed exoplanets."
We end up with 5,235 known worlds. About 4% are rocky planets like Earth or Mars. What
will the new year bring? More planets!" So far, the exoplanet catalogs offer a diverse
spectrum of planets in terms of composition and features. Small, rocky planets like Earth,
gas giants many times the size of Jupiter, and hot Jupiters in dangerously tight orbits around their
stars are among them. Meanwhile, the list includes "super-Earths," which are potentially larger
rocky planets than our own, and "mini-Neptunes," which are smaller copies of our system's Neptune.
But what exactly are exoplanets, and why are we searching for them?
An exoplanet is simply a planet that orbits a star outside of our own solar system. These
planets can range in size from small, rocky worlds like Earth to massive gas giants like Jupiter.
And while exoplanets were once thought to be a rare occurrence, we now know that they
are actually quite common. In fact, it is estimated that there could be billions of
exoplanets in our own galaxy alone. So, why are we searching for these distant worlds? For one,
the discovery of exoplanets helps us better understand the diversity of planetary systems
in the universe. It also gives us the opportunity to search for signs of life beyond our own planet.
While we don't yet have the technology to detect life directly on exoplanets, we can search for
clues in their atmospheres and surfaces that might suggest the presence of living organisms.
But searching for exoplanets is no easy task. These planets are incredibly small
and faint compared to their parent stars, making them difficult to detect. However,
over the past few decades, astronomers have developed several methods for finding exoplanets.
One of the most successful methods is called the radial velocity method,
which looks for the slight wobble of a star caused by the gravitational pull of an orbiting planet.
Another method is the transit method, which looks for a slight
dip in the brightness of a star as an exoplanet passes in front of it.
In addition to these methods, we also have several powerful telescopes and spacecraft
that are specifically designed for the search for exoplanets. The Kepler Space Telescope,
for example, has discovered thousands of exoplanets by looking for the transit method.
The Hubble telescope was our primary telescope for looking deep into the universe and also observing
these alien planets. Now, it has a successor. The James Webb Space Telescope, the most powerful
space telescope ever built, will peek into the atmospheres of several of these planets, providing
scientists with unique insights into these unknown orbs. As the 2022 year has come to an end,
these are some of the most exciting, strange, and intriguing exoplanet discoveries made this year.
5. A Planet that has metal clouds and raining gems
Many distant exoplanets are discovered by directing specialized telescopes,
like NASA's famed Kepler telescope, towards distant stars and searching for dips in their
brightness. It strongly suggests that a planet passed in front of that star.
Scientists may sometimes get a peek at an exoplanet's atmosphere (a feat that will become
more common with the powerful Webb telescope). Researchers have discovered that flying metals
and diamonds are likely to exist on the colder side of WASP-121 b, an exoplanet located 855
light-years from Earth. It's cold enough there for high-altitude metals like magnesium, iron,
vanadium, chromium, and nickel to condense as clouds. What might such clouds even look
like? It would be a hard question to answer for us as cloud formation itself is complicated,
and we do not have such clouds in our solar system to observe and study.
These alien clouds might mirror Earth's dust storms. Some clouds may be blue or crimson in hue.
Others are grayish or green in color. And, on occasion, the clouds may condense further into
droplets, resulting in diamonds pouring from the sky. In addition to its metallic clouds,
WASP-121b is also notable for its extreme size and mass. It is about twice the size of Jupiter
and has a mass about 1.2 times that of Jupiter. This combination of size and mass makes WASP-121b
one of the densest known exoplanets, with a density of about 4 grams per cubic centimeter.
4. THE HULK PLANET
A newly discovered blazing-hot "super-Earth" is one of the largest ever identified,
an exoplanet coated in lava with a "year" that lasts barely half a day.
This super-Earth is one of the most massive ever discovered.
TOI-1075 b was discovered by NASA's Transiting Exoplanet Survey Satellite
(TESS) satellite. Because of its closeness to its parent system, a tiny red-orange star
around 200 light-years distant from Earth, it has a superheated surface with a temperature of
roughly 1,922 degrees Fahrenheit (1,050 degrees Celsius). Exoplanets are often labeled with
characteristics that relate them to planets closer to home. "Hot Jupiters," for example,
are gas giants that orbit close to their parent stars. Astronomers are intrigued by super-Earths
because they are expected to be widespread in the Milky Way, despite the fact that none exist
in our solar system. If TOI-1075 b were closer to Earth and people could visit, their weight on the
planet's surface would quadruple since TOI-1075 b is almost 10 times more massive than Earth.
In addition to its scorching environment and 14.5-hour orbit, it's one of the most massive
super-Earths—rocky exoplanets bigger than our own. Astronomers are fascinated with super-Earths
because they are expected to be numerous across the Milky Way, despite the fact that none exist
in our solar system. TOI-1075 b has a mass that is approximately ten times that of Earth.
3. A strange planet in the form of a "rugby ball."
The European Satellite Agency's (ESA) Cheops space telescope (short for
CHaracterising ExOPlanet Satellite) discovered WASP-103-b, a planet twice the size of Jupiter,
orbits its star in less than a day. This generates tremendous dragging on the planet, similar to how
the moon pushes on tides on Earth. This pulling eventually distorted the planet's spherical shape.
One of the most unusual features of WASP-103b is its shape, which has been described as
"rugby ball-like" due to its elongated, oblong appearance. This shape is thought to be caused
by the strong tidal forces exerted on the planet by its parent star. As WASP-103b orbits its star,
these tidal forces stretch and deform the planet, giving it its distinct shape.
In addition to its unusual shape, WASP-103b is also notable for its extreme temperatures. It is
classified as a "hot Jupiter," a type of exoplanet that is similar in size and mass to Jupiter but
much closer to its parent star. This proximity to the star means that WASP-103b is subjected to
temperatures of up to 4,400 degrees Fahrenheit, which is hot enough to vaporize many elements.
The Cheops satellite detects minute variations in light and was able to detect the planet's unusual
form when it passed in front of its star. The influence of tidal deformation on an exoplanet
transit light curve is relatively modest, but we can detect it for the first time because
of Cheops' great accuracy. Overall, WASP-103b is an interesting and unusual exoplanet that
is providing scientists with valuable insights into the atmospheres and shapes of these distant
worlds. Its unique shape and presence of water vapor make it a fascinating object of study.
2. A Rare “SUPER NEPTUNE”
Astronomers discovered a "super Neptune" (a planet somewhat bigger than Neptune) with water
vapor in its atmosphere 150 light-years away from Earth. That is unusual. TOI-674b is classified as
a "super Neptune," a type of exoplanet that is similar in size to Neptune but much denser. It
has a mass about seven times that of Neptune and a density of about 8 grams per cubic centimeter,
making it one of the densest known exoplanets. One of the most interesting features of TOI-674b is
its relatively close proximity to its parent star. It orbits its star at a distance of only about
0.05 astronomical units, which is much closer than the distance between Neptune and the Sun.
This proximity to the star means that TOI-674b is subjected to intense radiation and temperatures
of up to 2,200 degrees Fahrenheit. Despite these extreme conditions,
TOI-674b is believed to have a thick atmosphere that is rich in water vapor and other molecules.
This is surprising, as such high temperatures would normally be expected to cause the
planet's atmosphere to be stripped away by the intense radiation from the star.
Despite the recent discovery, many issues remain, including how much water vapor is
in its atmosphere. However, TOI-674 b's atmosphere is significantly simpler to examine than that of
many exoplanets, making it an ideal candidate for further study. Maybe James Webb will peer
deeper into the planet's atmosphere next year and give us a better understanding of the exoplanet.
1. A Jupiter Sized Hidden World
Astronomers and citizen scientists collaborated to
locate a mystery Jupiter-sized planet orbiting an alien star.
If their orbital predictions are right, they should be able to view it again in February.
The planet, TOI-2180 b, is just 379 light-years distant from Earth. The exoplanet is around the
same size as Jupiter but almost three times more massive. This density differential shows that the
planet developed differently from Jupiter. This planet is remarkable in that it takes 261 days
to circle its star, which is far longer than the majority of distant gas giants identified to date.
Another oddity is the planet's temperature, which is an unusually moderate 170 degrees
Fahrenheit on average (77 degrees Celsius). TOI-2180 b is warmer than Jupiter and Saturn,
yet it is still cold in compared to many other massive exoplanets. It's a good stepping
stone between most of the large exoplanets we've discovered and incredibly cold Jupiter and Saturn.
This temperature difference remains a mystery, but it might be investigated
further by other observatories, such as NASA's recently built James Webb Space Telescope.
The hunt for exoplanets will continue in 2023. With the all powerful James Webb,
we can hope for detailed observations of the atmospheres of these exoplanets.
So, what was the most exciting exoplanet for you? How many exoplanets do you think
we will discover this year? Drop your guess in the comment section below.