Start counting down to launch.
Last year, space fans witnessed the long-awaited first test flight of NASA's moon-bound Space Launch System rocket, but this year could see even more action at the launch pad, as a slate of new rockets look to make their debut.
"There's a lot to look forward to," said Colleen Anderson, a historian of technology at the National Air and Space Museum in Washington, D.C. "It's going to be an interesting time with first flights for a lot of new launch vehicles."
From new boosters to replacing old workhorses to the much-anticipated first flight of a huge rocket billed as the tallest and most powerful ever built, here's what to look for this year.
Few rockets attract the kind of curiosity and awe that SpaceX's behemoth Starship does.
Standing at a towering 394 feet (with a 164-foot-tall spacecraft also known as Starship attached), the fully stacked launch vehicle is taller than NASA's retired Saturn V rocket that was used during the Apollo moon program, as well as the agency's new Space Launch System.
The next-generation rocket is designed for missions to the moon and eventually Mars.
The huge booster will play an important role in NASA's Artemis program, which aims to return astronauts to the moon and establish bases on the lunar surface. If successful, the rocket will not only pave the way for more regular flights to the moon, but will also lower the cost of such journeys.
"Starship has the opportunity to really revolutionize the way that we do space transportation, so it's a big deal," said Laura Forczyk, the executive director of Astralytical, a space consulting firm based in Atlanta.
Starship is what's known as a super heavy-lift launch vehicle, which refers to rockets that can carry more than 110,000 pounds into orbit. SpaceX has said its reusable Starship could lift up to 330,000 pounds to low-Earth orbit.
Starship is expected to launch on its first uncrewed orbital flight this year, though no specific date has been announced by SpaceX. Last month, the company said it had completed a "wet dress rehearsal," which involved fully fueling the rocket with 10 million pounds of propellant, as would be done prior to liftoff.
Next, SpaceX will likely conduct another key safety test by firing up all 33 Raptor engines on the booster's first stage - a demonstration known as a "static fire test." Then, once the company obtains a license from the Federal Aviation Administration, Starship could finally take flight from SpaceX's launch site in Boca Chica, Texas.
Another new rocket that could play a critical role in the years ahead is the Vulcan Centaur, developed by the Denver-based United Launch Alliance.
The heavy-lift Vulcan Centaur is designed to carry satellites and other spacecraft to various orbits around Earth. The roughly 200-foot-tall rocket will be used for commercial launches, as well as for launches on behalf of NASA and the Space Force.
The Vulcan Centaur is expected to eventually replace United Launch Alliance's workhorse Atlas V and Delta IV Heavy rockets.
The rocket's various parts are being assembled at Florida's Cape Canaveral Space Force Station ahead of its first flight. That launch, known as Certification-1, will carry two demonstration satellites to low-Earth orbit, place a commercially built lunar lander in a highly elliptical orbit above Earth, and deliver another payload to a trajectory that will take it beyond the Earth-moon system.
The Vulcan Centaur's debut represents an exciting opportunity for United Launch Alliance, which has been a longtime contractor for NASA and the military. It also sets up the new booster to replace some of the most-used rockets that are currently available, according to Anderson, the technology historian.
"With the Atlas V and the Delta IV presumably going into retirement, this rocket is very important for U.S. launch capabilities at the moment," Anderson added.
American space companies are not the only ones busy designing new rockets that could take flight this year. Arianespace, headquartered in France, is readying a new booster named Ariane 6 for its maiden launch.
The nearly 200-foot-tall rocket is designed to deliver satellites and other payloads into orbit around Earth. The booster is expected to replace the heavy-lift Ariane 5 rocket, though it would be capable of operating at a lower cost.
Anderson said the Ariane 6 will provide important mid-range launch capabilities but will likely face stiff competition from other companies, including SpaceX.
Like Arianespace's other rockets, the Ariane 6 will launch from a spaceport in South America, located northwest of Kourou in French Guiana.
No specific date has been announced yet for the first test flight.
The Japan Aerospace Exploration Agency is readying its new rocket for its inaugural flight this month.
The booster, known as H3, will carry an Earth observation satellite into orbit on the test flight. Liftoff is currently scheduled for Feb. 12.
The rocket will launch from Japan's Tanegashima Space Center, on the southeast coast of Tanegashima, an island south of Kyushu.
Other rockets in the works
Several other American private companies are also developing new rockets that could take flight this year or in the years ahead.
Relativity Space, an aerospace firm headquartered in Los Angeles, is aiming to debut a 3D-printed rocket dubbed Terran 1. While 3D-printed parts have been used to build boosters before, this would be the first rocket developed entirely with additive manufacturing.
ABL Space Systems, a company headquartered in El Segundo, California, tried to launch its RS1 rocket on its debut flight last month, but was unsuccessful. The Jan. 10 launch took place at the Pacific Spaceport Complex - Alaska on Kodiak Island. Shortly after the scheduled liftoff, ABL reported that the rocket failed to reach orbit.
"After liftoff, RS1 experienced an anomaly and shut down prematurely," the company tweeted, adding that it was working with officials from the FAA and the Alaska spaceport in the aftermath.
Though not a new rocket, California-based Rocket Lab launched its Electron rocket for the first time on U.S. soil Jan. 24. Rocket Lab's previous missions occurred in New Zealand. For the Virginia launch, the booster lifted off from NASA's Wallops Flight Facility in Virginia, carrying three small satellites into orbit. The company is developing a new rocket, called Neutron, but it doesn't expect the booster to fly until next year.
This article was originally published on NBCNews.com