NASA's DART asteroid redirect mission takes off from Vandenberg on a Falcon 9 rocket.
NASA's DART (Double Asteroid Redirect Test) mission was launched onboard a Falcon 9 rocket by SpaceX.
DART is a demonstration mission designed to see what happens if an asteroid is intentionally hit.
The asteroid moon Dimorphos will collide with DART in October 2022.
The small spacecraft was launched from SLC-4E at Vandenberg Space Force Base on November 23rd at 10:21 a.m. Pacific Time (6:21 a.m. UTC on November 24th).
This was the 26th Falcon 9 launch of 2021, and the third flight of Falcon 9 first stage B1063.
It was the start of a flurry of Falcon 9 launches in November and December, with four more scheduled before the end of the year.
From Vandenberg, B1063 launched the Sentinel-6 Michael Freilich satellite, and from Cape Canaveral, it launched the Starlink L28 mission.
If the flight had been delayed, the launch time would have been one minute earlier each day.
The overall launch window for the mission was February 15, 2022.
The Falcon 9 took off on a southbound trajectory, with stage separation taking place two minutes and thirty seconds after takeoff.
The first stage then flew to the drone ship Of Course I Still Love You, which was stationed off the coast of Baja California.
The two fairing halves will be recovered from a location south of the drone ship in the future.
The second stage engine was restarted after a brief coast period to send DART on an escape trajectory away from the Earth.
The asteroid Didymos and its moon Dimorphos will be intercepted by DART in 10 months.
Following the cutoff of the second stage, the payload adapter, a new smaller design that had its first flight, released DART.
The spacecraft will then deploy its two 27.9-foot-long ROSA solar arrays, allowing it to become power-positive, a critical step that must occur soon after separation.
During its journey to the asteroid and its moon, DART will put a number of new technologies to the test.
The NEXT-C ion engine, which was inspired by Dawn's flight to the asteroids Vesta and Ceres, is one example.
To send and receive data, DART will also test a new compact high-gain antenna called the Radial Line Slot Array.
In addition, to improve power generation, a portion of the probe's solar array is equipped with reflectors and higher-efficiency solar cells.
DART's primary mission, on the other hand, is to test a technique for altering an asteroid's orbital path.
This spacecraft will be maneuvered autonomously to collide with the moonlet Dimorphos.
The kinetic impact is designed to alter the moonlet's orbital velocity and path around Didymos.
With a period of 11 hours and 55 minutes, Dimorphos is currently orbiting Didymos.
The collision of DART with Dimorphos is expected to change DART's orbital time from 11 hours and 45 minutes to 11 hours and 45 minutes.
However, because this is the first time a solar system body's orbit has been purposefully altered by a spacecraft impact, the impact's actual effects will be studied using a variety of methods and may differ from pre-flight projections.
DART will launch LICIACube, an Italian-built CubeSat, ten days before the kinetic impact, to image the impact and the far side of Dimorphos.
DART's single instrument, a camera called DRACO (Didymos Reconnaissance and Asteroid Camera for Optical Navigation), will see Dimorphos as a tiny dot 60 minutes before impact.
Its final approach will begin at this point.
DART will use its SMART NAV system and images from DRACO to guide itself to the impact with Dimorphos.
These images will be used to classify Dimorphos' surface, which could range from a strew of rubble to solid rock.
The spacecraft maneuvering will be completed two minutes before impact.
Dimorphos will fill the camera's field of view 20 seconds before impact, and the images will continue to be transmitted until the collision.
The debris created by the impact will be imaged by LICIACube, which will serve as a gauge of how powerful the event was.
Ground-based telescopes will also be used to determine the extent to which Dimorphos' orbit around Didymos has shifted.
Because of the DART team's chosen trajectory, Didymos is unlikely to be hit by any debris from the collision.
For several reasons, the Didymos system was chosen for this mission.
The main reason for this is that the system approaches Earth but never crosses its orbit, posing no threat to the planet.
The impact of DART would have no effect on this.
DART will also arrive at Dimorphos relatively quickly due to its close proximity to Earth, which necessitates a less powerful launch vehicle.
Dimorphos has a diameter of about 170 meters, which is about the same as a football stadium, and is within the range of objects that would pose the greatest threat to Earth.
Its parent body has a diameter of about 780 meters.
In 2027, the DART mission will be followed by the HERA mission of the European Space Agency, which will investigate the changed Didymos system and the altered Dimorphos moonlet.
The information gathered by these missions will be used to help divert future asteroids using the kinetic impact method, which is one of several proposed methods to avoid a catastrophic asteroid impact like the one that wiped out the dinosaurs 65 million years ago.
(Photo credit: NSF/Jack Beyer: Falcon 9 lifts off with DART.)