We live in a golden age of astronomy and space exploration. As the Hubble era gives way to the James Webb Space Telescope launching in 2018, expect many new and wonderful discoveries to come. Researchers are now linking up radio telescopes across continents that are able to resolve objects scarcely imagined by early astronomers. Missions such as the Transiting Exoplanet Survey Satellite (TESS) will extend the Kepler Space Telescope’s legacy across the entire sky, sending the number of known exoplanets into the tens of thousands. Here are five developments on the cutting edge of space science.
5. We May Soon Peer Inside Black Hole at Our Galaxy’s Core
What does a black hole look like? We may soon have a sort of portrait of the massive black hole at the center of our galaxy, thanks to a venture linking radio telescopes across the globe. Starting in April 2017, the Event Horizon Telescope project will link radio telescopes on four continents. Using a process known as very long baseline interferometry, this configuration will effectively give the array a resolution of a single dish thousands of miles wide. The target: the Sagittarius A* (pronounced “A-Star”) black hole at the core of our galaxy. A monster with 4.1 million times the mass of our Sun, we can infer its presence by stars that are seen in the dusty core, whipping around it at terrific speeds. By imaging the black hole’s boundary — its event horizon — scientists may be able to test Einstein’s general theory of relativity under extreme conditions. Expect to see images of the shadow of Sagittarius A* by late 2017 or early next year.
4. Expect Discovery of More Earth-Like Planets
How common are terrestrial planets? This is a key factor in the Drake Equation: as far as we can tell, life needs a world similar to the Earth where interesting chemistry is ongoing for life to get started. NASA’s announcement earlier this year of the discovery of the TRAPPIST-1 system with seven terrestrial planets suggests that Earth-sized worlds may be far more common than scientists once expected. The launch of the aforementioned James Webb Space Telescope in 2018 should make detection of these worlds easier. Webb’s instrument package will be able to detect chemical traces of water, methane, oxygen, ozone, and other components of an exoplanet’s atmosphere. Webb also will be able to analyze temperatures and surface pressures on these distant worlds.
But don’t build that interstellar ark to meet our space neighbors just yet. Take that recently discovered TRAPPIST-1 system, located 39.5 light years distant. The host red dwarf star is a type notoriously known for producing planet-sterilizing flares. Perhaps life could still establish itself underground or on the far side of a tidally locked world, although it would be vastly different from life here.
3. Mission to Jovian Moon May Find Life Beyond Earth
Is there life elsewhere in the solar system? One of the best possibilities for life beyond Earth is in the seas of Europa. NASA plans to send a flyby mission and possibly a lander to the Jovian moon in the next decade. The Europa Clipper mission will depart Earth sometime around 2022. It will take three to six years (depending on the launch window) to reach Europa, and the mission will have to thread the dangerous and damaging radiation belts that surround Jupiter.
The idea of incorporating a Europa lander on the mission has been a fiercely contested on-again, off-again affair. Certainly, we’d love to ultimately get a submersible down into the oceans of Europa to, in the words of astronomer Neil deGrasse Tyson, “See if anything swims up to the camera lens.” Photosynthesis is impossible under the Europan ice. Instead, life would have to derive energy from geothermal heat generated from the flexing of the moon’s core by Jupiter’s gravitational pull. The trouble is, the ice above the underground sea is several kilometers thick. Still, finding that life existed elsewhere in the solar system would have far-ranging implications, suggesting that such occurrences are common in the cosmos.
2. Discovery of Gravitational Wave Events Creates New Field
On Sept. 14, 2015, a gravitational wave rippled through the Earth. This event occurred 1.3 billion light years distant, caused by the merger of two black holes. This occurred just in time for the pair of recently upgraded Advanced Laser Interferometer Gravitational Wave Observatory LIGO detectors, one in Washington State, the other in Louisiana, to witness the event. This marked the first direct detection of gravitational waves as postulated by Albert Einstein’s general theory of relativity a century ago. Events such as black hole and pulsar mergers might occur daily across the universe … but how common are gravitational wave events? LIGO scientists announced that first detection of gravitational waves last year. This promises to open up a new field of astronomy, completely separate from the electromagnetic spectrum. A third LIGO detector will go online in India over the next decade, along with upgrades for Enhanced LIGO, which will refine the ability to pinpoint the origin of a gravitational wave source (a gravitational wave passes through the Earth at the speed of light). Farther off, expect the European Space Agency to take the hunt for gravitational waves to space in 2030, with the Laser Interferometer Space Antenna (LISA).
1. Effort Underway to Send Tiny Probe to Nearest Star
Can we reach another star? In August 2016, the Pale Red Dot project announced the discovery of an exoplanet orbiting the nearest star to our solar system, Proxima Centauri. Trouble is, even this nearest star system is 4.2 light years distant. Moving at 38,000 mph, the Voyager 1 spacecraft escaping the solar system would take almost 74,000 years to make the journey. But there are concepts out there aiming to make the trip over a much shorter time. The Breakthrough Starshot initiative has a plan to send a tiny spacecraft four light years distant in about 20 years. Announced by Russian billionaire Yuri Milner in 2016 as one of his Breakthrough Initiatives, this project would incorporate a lightsail propelled by an Earth-based laser array and/or the solar wind to slowly accelerate the spacecraft to 20% the speed of light.
Of course, there are many problems to solve; the nanocraft would have to weigh under 100 grams (that’s 3.5 oz.; a U.S. nickel weighs 5 oz.), and all of this would somehow need to carry instrumentation, guidance and communication. It must also, after an acceleration and cruise phase, perform a long period of deceleration; otherwise it would fly right through the Proxima Centauri system in just a few hours. Finally, there’s no guarantee that a dust grain impacting the spacecraft while it’s moving at a fifth of the speed of light won’t end the mission altogether. Still, the very idea that we might make it to the nearest star within a few decades is an encouraging one.