Yesterday morning at 7:50am EDT, United Launch Alliance's Atlas V rocket launched from Cape Canaveral, Florida, carrying a new rover destined for the red planet.
The last rover that was launched to Mars from the United States was NASA's Curiosity rover back in November of 2011, which was also launched on an Atlas V rocket by ULA in the same configuration. The rocket flew in its 541 configuration, meaning it had a 5 meter faring (with the second stage inside), 4 Solid Rocket Boosters, and 1 RL-10 centaur upper stage engine. To this day the Curiosity rover is still roaming (slowly) on Mars' surface gathering scientific data and photos everyday after ~5.5 years, despite only having a planned ~2 year lifespan.
Perseverance will land on Mars on February 18th, 2021 and has a plethora of technology advancements compared to Curiosity. One of the big technologies on this rover is the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE), which will take the CO2 from Mars' atmosphere and produce Oxygen from it. This will provide a lot of data for future Mars colonies as well as producing Liquid Oxygen for refueling rockets on the surface.
A quick list of all new technologies on this rover are:
Mastcam-Z: Advanced camera system with panoramic and stereoscopic imaging with the ability to zoom. Also can determine mineralogy of the surface.
SuperCam: Providing images, chemical composition analysis, and mineralogy at a distance.
Planetary Instrument for X-ray Lithochemistry (PIXL): Maping fine-scale elemental composition of Martian surface materials. Providing more detailed detection and analysis of chemical elements than ever before.
Scanning Habitable Environments with Raman & Luminescence for Organics and Chemicals (SHERLOC): The first UV Raman spectrometer to fly to the surface of Mars and will provide fine-scale imaging to map mineralogy and organic compounds.
Mars Environmental Dynamics Analyzer (MEDA): Providing measurements of temperature, wind speed and direction, pressure, relative humidity, and dust size/shape.
The Radar Imager for Mars' Subsurface Experiment (RIMFAX): A ground-penetrating radar that provides centimeter-scale resolution of the geologic structure of the subsurface
Source for these technologies and more info on Perseverance: https://mars.nasa.gov/files/mars2020/Mars2020_Fact_Sheet.pdf
Perseverance also has a set of sensors to test autopilot softwares for navigation and hazard avoidance, which will allow the rover to drive faster in challenging terrain.
Being carried along with Perseverance, a tiny helicopter named Ingenuity will be deployed on the Martian Surface to test propeller powered spacecraft in Mars' atmosphere. It won't do much in terms of photos or scientific data, but is more of a stepping stone in testing this technology to see if it's possible to send spacecraft to Mars that can quickly fly around in the atmosphere as well as hover to gather images of landscapes and possible future landing sites in greater detail.