NASA/ESA/A. van der Wel (Max Planck Institute for Astronomy)/H. Ferguson and A. Koekemoer (Space Telescope Science Institute)/The CANDELS team
10. Dwarf galaxies and stellar formation
Dwarf galaxies that lived about 9 to 10 billion years ago had bursts of star formation, which implies that many, if not most, of the stars in such galaxies in the present-day universe form in the same way. This image shows 18 of the 69 galaxies studied.
9. Curiosity tastes martian dust
The Mars Science Laboratory's seven minutes of terror became the engineering achievement of the year August 5/6 as Curiosity landed safely on the Red Planet.
Adam Block/Mount Lemmon SkyCenter/University of Arizona
8. Base of black hole's jet spied
Astronomers used an Earth-sized radio array to resolve the base of M87's high-energy jet, seen here in visible light, a first in the field.
7. DIY funding ramps up
Privately funded astronomical instruments are becoming more popular, the way observatories used to be financed. In 2012, the organization behind the Giant Magellan Telescope announced it wouldn't apply for NSF funding, the Discovery Channel Telescope saw first light without any state or federal assistance, and the B612 Foundation revealed its plans to develop a privately funded space telescope.
NASA/JPL-Caltech/UCLA/MPS/DLR/IDA/PSI
6. Dawn uncovers Vesta's secrets
The Dawn spacecraft left Vesta in September after more than a year examining the asteroid. Over that time, scientists learned that the object appears more planet-like than asteroid-like.
5. IBEX reveals a softer edge
Data from the Interstellar Boundary Explorer (IBEX) showed that the Sun moves relative to the interstellar medium 7,000 mph (11,300 km/h) slower than expected and thus its protective heliosphere has a "bow wave" outer structure.
4. Exoplanets discovered in surprising situations
Scientists uncovered new worlds that orbit binary stars (as seen in the illustration), ones that orbit suns lacking expected heavier elements, ones that survived their star's red-giant phase, and even a world orbiting a sun in the star system nearest to ours.
3. Commercial craft takes historic flights
SpaceX's Dragon capsule made history as the first privately developed craft to berth with the International Space Station in May. The company launched its first of many regular supply runs to the station five months later.
2. Astronomers question how stars blow up
A type Ia supernova can result from two different paths, and more discoveries in 2012 questioned whether the energy emitted during the explosion is consistent. The concern has big consequences: Such supernova measurements have been used to measure the universe's accelerating expansion.
1. Physicists detect long-sought particle
Two detectors at CERN's Larger Hadron Collider found a new particle that has characteristics consistent with the Higgs boson, the last missing piece of physics' standard model.