New space discoveries in 2018 helped scientists understand some of the mysteries of our ever-expanding universe. Astronomers witnessed the death of a star, discovered clusters of black holes and the absence of dark matter, while robots explored Mars. Several exciting new missions launched that will continue into 2019, and work continues on future missions, such as the James Webb Space Telescope. Five discoveries stand out as contributing to a deeper understanding of space.

Evidence for Thousands of Black Holes at Center of Milky Way

Columbia University researchers detected a dozen black holes surrounding the supermassive black hole at the center of the Milky Way. This new evidence supports the theory that the supermassive black hole, called Sagittarius A*, is actually surrounded by roughly 10,000 other isolated black holes plus as many as 500 black holes paired with stars, according to Science Daily. The researchers examined archival data from a NASA telescope known as the Chandra X-ray Observatory and searched for faint but consistent X-ray signatures that can indicate black holes. This new study confirms a theory about gravitational waves, helps scientists understand how large black holes interact with smaller ones and suggests that similar black hole clusters exist in the centers of most galaxies. NASA announced, “This recent analysis using Chandra data is the first observational evidence for such a black hole bounty.”

The Death of a Zombie Star

Scientists already have a strong understanding of what happens when a star dies and how supernovas work, but in 2018, astronomers discovered that iPTF14hls appears to have died and come back to life multiple times. What’s going on with this so-called zombie star? Normally, when a star dies, it emits a bright light for a short period of time while imploding during a supernova event. But, according to Space.com, even though iPTF14hls seemed like it died about 60 years ago, it now appears to be pulsing, with a brighter-than-normal supernova.

A New Galaxy With No Apparent Dark Matter

Most of the material in the universe is dark matter, but a Milky Way-sized galaxy named NGC 1052-DF2 seems to be missing this essential ingredient for a galaxy. Astrophysicist Alberto Conti of Northrop Grumman explained, “‘In astronomy, if we don’t know what something is, we call it ‘dark.'” According to Science Daily, NGC 1052-DF2 only has 1/400th of the expected amount of dark matter, which remains a mystery to scientists.

Detecting the Oldest Stars in the Universe

Another discovery in 2018 gives us some new clues about dark matter. A team of American astronomers detected signals from the oldest stars in the universe, which formed just 180 million years after the Big Bang, according to Sky & Telescope. The absorption was stronger than predicted, suggesting that the gas the starlight had passed through was colder than expected. So what stole the energy? Sky & Telescope explained that the thief was likely dark matter, which presumably interacted with ordinary matter in the early days of the universe.

Mars Exploration

In June 2018, NASA announced that the Curiosity rover found organic material preserved in rocks on Mars and methane in the planet’s atmosphere. While not necessarily indicative of life itself, the findings suggest the planet could have supported ancient life, according to NASA. Then, in late November, the InSight Mars lander arrived to dig deeper into the Red Planet to gather more data.

What’s Next: New Missions

Insight was one of several successful launches to collect data that could lead to exciting new discoveries in 2019. The Parker Solar Probe is a robotic spacecraft that is going 3.83 million miles away from the sun. It launched in August, and in September, NASA reported it had started to receive data. Additionally, the Transiting Exoplanet Survey Satellite (TESS) launched in April to search for planets outside of our solar system, including, according to NASA, planets that could support life.

Looking ahead, the James Webb Space Telescope is expected to launch in 2021. It is optimized for infrared wavelengths, which means it will be able to see things that are invisible to its predecessor, the Hubble Space Telescope. NASA says the Webb telescope will be a giant leap forward in our quest to understand the universe and our origins.

If you’re interested in working with the teams fueling the next generation of space discoveries, take a look at Northrop Grumman careers here.