Buzz
Just like a photographer capturing that perfect shot, astronomers occasionally find themselves at the perfect spot, at the perfect time, using the right wavelength to uncover something exceptional and rare.
10. First Glimpse of a Supernova
Astronomers have observed numerous supernovae after they occurred. Recently, however, they managed to catch two during the early stages of their demise and witnessed the shock wave produced by a dying star.
Both stars were red supergiants, aging stars nearing the end of their lives. The smaller of the two still surpasses our own Sun, with a radius 270 times its size. The larger one is even more massive, with a radius 460 times bigger than our relatively modest solar star.
Astronomers observed the shock wave from the smaller star, but the larger one was so massive that its shock wave didn’t reach the surface. On the upside, supernovae enrich the universe with new elements, as the immense pressures and temperatures force the universe’s heavier elements to collide, and the shock wave rips through space at speeds of up to 40,000 kilometers per second (25,000 mi/s).
9. Light from the Big Bang Aids Astronomers in Spotting a Black Hole
The Cosmic Microwave Background (CMB), the faint light left behind from the big bang, is finally proving its worth, helping astronomers spot a black hole from when the universe was just 2.7 billion years old.
The lingering energy from the big bang boosted the black hole’s escaping electrons into the X-ray range, making them visible to the Chandra X-ray Observatory in orbit. This uncovered a 300,000-light-year-long jet streaming from the black hole, its X-ray brightness amplified 150 times by the CMB.
Normally, such jets are seen through radio waves, but this radio-silent B3 0727+409 system indicates that we may be overlooking a whole group of black holes that are only visible under specific conditions.
8. Disintegration of a Solar System
In the Virgo constellation, 570 light-years away, WD 1145+017 gave astronomers an unprecedented view: the disintegration of a solar system.
The villain in this cosmic drama is a white dwarf, an Earth-sized remnant of a dead star, incredibly dense but not powerful enough to trigger a supernova. Instead, it expanded drastically and shed its outer layers.
The hero of the story is a small rocky body, about the size of a large asteroid, the first planet discovered orbiting a white dwarf. Surprisingly, this world seems to have survived its star’s death to some degree, but it’s slowly being torn apart, piece by piece, as the star’s immense gravity and radiation wreak havoc.
7. The Newborn Planet
Most planets in the universe are ancient, having orbited their long-lived stars for billions of years. With stars like these potentially lasting trillions of years, it's rare to encounter anything young. However, a team of Kepler and Keck telescopes recently observed K2-33b, a fully formed exoplanet just 5–10 million years old, making it a newborn in comparison to the over 3,000 exoplanets discovered to date.
The planet is Neptune-sized and orbits its star 15 times closer than Mercury orbits the Sun. More intriguingly, K2-33b and other recently discovered young, close-in planets challenge the previously held belief that massive planets only form farther from their stars, where it's cooler and calmer.
6. The Binary-Binary System
Astronomers have already cataloged binary planets and binary stars, but after an eight-year, seven-telescope, 30-astronomer endeavor, they’ve now confirmed the existence of the HD 87646 binary-binary system: a pair of objects bound to two companion stars.
The two stars are rather unimpressive. The primary star, the dominant one around which the paired objects orbit, is about 12 percent more massive than the Sun. Its companion, located 22 astronomical units (AU) away, is 10 percent smaller than the Sun.
The two objects themselves are surprisingly enormous. One is a massive planet, 12 times more massive than Jupiter, and the other is a brown dwarf, a failed star that accumulated only 57 Jupiter masses and never quite achieved its stellar potential. With the two bodies orbiting their stars at distances of 0.1 and 1.5 AU, astronomers are uncertain how such a bulky system can remain stable or how it even formed, since protoplanetary disks typically don’t contain such large amounts of matter.
5. A Comet Without a Tail
Among the many asteroids and icy objects that race through our solar system, C/2014 S3 stands out as a comet without a tail. Astronomers are puzzled about what to call it, so they’ve coined a new classification—“manx” comet, after the tailless breed of cat.
This first-ever manx comet originates from the Oort Cloud, a vast region of icy rock at the outermost edge of our solar system. It doesn’t have a tail like most comets because it contains a million times less ice than typical comets. Instead, it’s rocky, more like an asteroid, with just a faint trail of dust trailing behind it.
Unlike typical Oort Cloud comets, which frequently travel between the inner solar system and the asteroid belt, the Sun's rays have never touched the surface of this tailless comet. Astronomers believe it formed around the same time as Earth, only to be knocked into the distant reaches by some other celestial object. Unfortunately, this speedy comet-asteroid has passed by and won’t return for another 860 years.
4. Titan’s Once-in-a-Millennium Storm
Larger than Mercury, Saturn’s moon Titan is the second-biggest moon in the solar system, right after Ganymede. With its mountains, seas, and dense atmosphere, it’s a mini-Earth with a bizarre geological makeup. Like Earth, it experiences rain, but with temperatures around –180 degrees Celsius (–292 °F), the rain and all liquid bodies are made of methane. The alien raindrops are also larger than Earth’s and fall more slowly, due to Titan’s weaker gravity.
On Titan, some regions experience a light drizzle of methane each morning. If translated to Earth terms, this means three-day-long showers every 16 days. Elsewhere, rainfall is incredibly infrequent and may only occur once every 1,000 years.
These colossal storms on Titan can span vast areas. In 2010, an autumnal downpour drenched an area of roughly 500,000 square kilometers (200,000 mi).
3. The Outburst of Comet 67P
The Rosetta mission came to a bittersweet end in 2016. On February 19, the ever-entertaining Comet 67P/Churyumov-Gerasimenko delivered an early farewell surprise. With nine of the spacecraft’s eleven instruments unintentionally aimed at the comet, Rosetta captured an unexpected comet outburst. The comet brightened suddenly and spewed out a mixture of gas, plasma, and dust.
The cause was a landslide on the comet’s larger lobe, which is shaped like a dumbbell. Solar-induced thermal stresses cracked the comet’s surface, and the intense solar radiation quickly turned the underlying ice into gas. While the event might sound dramatic, the comet’s surface gravity is only .0001 times that of Earth, so it was likely far less violent.
Unfortunately, we won’t be able to observe Comet 67P again. On September 30, the Rosetta spacecraft concluded its 12-year mission in space with a soft, dusty crash-landing on Comet 67P/Churyumov-Gerasimenko.
2. A Before-And-After Nova
A classical nova occurs when a white dwarf in a binary system accumulates too much hydrogen from its companion, triggering a massive explosion that causes the dwarf to detonate. This event is incredibly bright, which is why astronomers have observed many novae, but only once have they witnessed the buildup leading to one, in a system 23,000 light-years from Earth.
The Optical Gravitational Lensing Experiment (OGLE) has been monitoring V1213 Centauri since 2003, noticing gradual brightness increases due to an unstable transfer of mass. Then, on May 8, 2009, astronomers witnessed the white dwarf erupt. This was the first time they tracked the pre-explosion buildup, and the system has continued to brighten, confirming the anticipated rise in mass transfer.
Now, the cycle repeats. As the mass transfer rate decreases, the dwarf will once again enter instability, setting off another chain reaction leading to another thermonuclear explosion.
1. The Infant Star That May Spawn Infant Stars
Among the monstrous stars in the universe, astronomers have discovered a baby star already weighing in at 30 times the mass of the Sun. Located 11,000 light-years away, Star G11.92-0.61 MM1 is still growing, drawing gas from its parent cloud and offering a rare opportunity to observe the early stages of a stellar behemoth's formation.
The largest stars are harder to detect. They burn through their fuel rapidly and die young. While a star like the Sun can survive for over ten billion years, the most massive stars only last a few million. Similarly, they grow much faster, with smaller stars taking around ten million years to form, while their massive counterparts can complete the process in just 100,000 years.
MM1 is encircled by a disc of rotating material, potentially concealing a smaller companion star that remains unseen. It’s also possible that the disc is so large it could eventually split apart due to gravitational forces, giving rise to a cluster of smaller protostars around the massive primary star.
