Supermassive black holes, lurking at the centers of most galaxies, are cosmic titans with masses ranging from hundreds of thousands to tens of billions times that of our Sun. A new animation from NASA visualizes the immense scale of these objects, comparing their shadows to familiar structures within our solar system, offering a stark contrast to the size of Earth.
, compared to the size of Mercury’s orbit. Credit: EHT Collaboration*
Direct measurements, many facilitated by the Hubble Space Telescope, confirm the existence of over 100 supermassive black holes. These behemoths grow through galactic mergers, where central black holes eventually combine. The Event Horizon Telescope (EHT) captured the first images of the supermassive black holes at the centers of M87 and our Milky Way galaxy in 2019 and 2022, respectively. These images revealed a bright ring of hot gas encircling a dark central region – the black hole’s shadow.
Defining a Black Hole’s Shadow
A black hole’s shadow is a region roughly twice the size of its event horizon, the point of no return. Light crossing the event horizon is trapped forever, while light passing nearby is bent by the immense gravity, creating the shadow effect. The NASA animation showcases 10 supermassive black holes, scaled by their shadow sizes, to illustrate their staggering proportions in comparison to Earth and our solar system.
From Dwarf Galaxies to Cosmic Behemoths
The animation begins with 1601+3113, a dwarf galaxy harboring a black hole with a mass 100,000 times that of our Sun. Its shadow is smaller than our Sun, a stark contrast when considering A Black Hole Compared To Earth.
Next is Sagittarius A*, the supermassive black hole at the center of our Milky Way. Its mass is 4.3 million Suns, and its shadow diameter is roughly half the size of Mercury’s orbit. This provides a clear perspective on the scale of a black hole compared to Earth’s orbital diameter.
The animation also features two black holes in galaxy NGC 7727, destined to merge in the next 250 million years. Their masses are 6 million and 150 million Suns, respectively.
Detecting the Mergers of Titans
Gravitational wave observatories have detected mergers of smaller black holes, but the merger of supermassive black holes will produce lower frequency waves detectable by space-based observatories like the upcoming Laser Interferometer Space Antenna (LISA), a joint project of NASA and the European Space Agency (ESA). LISA will measure these faint ripples in spacetime caused by the collision of colossal black holes, hundreds of millions of times the mass of our Sun.
M87 and TON 618: Giants Among Giants
The animation showcases M87’s black hole, with a revised mass of 5.4 billion Suns. Its shadow is so vast that light would take over two days to cross it. Finally, TON 618, one of the most massive known black holes, contains over 60 billion solar masses. Its shadow is so immense that light would take weeks to traverse it. Comparing a black hole like TON 618 to Earth highlights the truly incomprehensible scale of these cosmic objects.
The comparison of a black hole to Earth underscores the vastness of the universe and the incredible power of these celestial objects. From dwarf galaxies to the largest known black holes, the animation offers a captivating journey through the realm of supermassive giants.
