supermassive black hole tagged posts

Milky Way had a Blowout Bash 6 million years ago

Credit: Harvard-Smithsonian Center for Astrophysics

Credit: Harvard-Smithsonian Center for Astrophysics

The center of the Milky Way galaxy is currently a quiet place where a supermassive black hole slumbers, only occasionally slurping small sips of hydrogen gas. But it wasn’t always this way. A new study shows that 6 million years ago, when the first human ancestors known as hominins walked the Earth, our galaxy’s core blazed forth furiously. The evidence for this active phase came from a search for the galaxy’s missing mass.

Measurements show that the Milky Way galaxy weighs about 1-2 trillion times as much as our Sun. About 5/6 of that is in the form of dark matter. The remaining 1/6 of our galaxy’s heft, or 150-300 billion solar masses, is normal matter...

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ALMA finds a Swirling, Cool Jet that Reveals a Growing, Supermassive Black Hole

Alma's close-up view of the centre of galaxy NGC 1377 (upper left) reveals a swirling jet. In this colour-coded image, reddish gas clouds are moving away from us, bluish clouds towards us, relative to the galaxy's centre. The Alma image shows light with wavelength around one millimetre from molecules of carbon monoxide (CO). A cartoon view (lower right) shows how these clouds are moving, this time seen from the side. The background colour image of NGC 1377 and its surroundings is a composite made from a visible light images taken at the CTIO 1.5-metre telescope in Chile by H. Roussel et al. (2006) (V filter; http://adsabs.harvard.edu/abs/2006ApJ...646..841R), and in filters r and i by ESO's VLT Survey Telescope [VST] Credit: CTIO/H. Roussel et al./ESO (left panel); Alma/ESO/NRAO/S. Aalto (top right panel); S. Aalto (lower right panel)

Alma’s close-up view of the centre of galaxy NGC 1377 (upper left) reveals a swirling jet. In this colour-coded image, reddish gas clouds are moving away from us, bluish clouds towards us, relative to the galaxy’s centre. The Alma image shows light with wavelength around one millimetre from molecules of carbon monoxide (CO). A cartoon view (lower right) shows how these clouds are moving, this time seen from the side. The background colour image of NGC 1377 and its surroundings is a composite made from a visible light images taken at the CTIO 1.5-metre telescope in Chile by H. Roussel et al. (2006) (V filter; http://adsabs.harvard.edu/abs/2006ApJ…646..841R), and in filters r and i by ESO’s VLT Survey Telescope [VST] Credit: CTIO/H. Roussel et al./ESO (left panel); Alma/ESO/NRAO/S...

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Gravitational Lens Zooms in on why some Quasars have the Radio turned down

Reconstruction of the lensed radio-quiet quasar HS0810+2554 after removing the effects of the lensing. Right: the data from the Karl G. Jansky Very Large Array showing what the source looks like after passage through the lensing galaxy. The images are not to scale - the lensed image appears to be many times larger in the sky than the actual size of the source. Credit: N Jackson/NRAO

Reconstruction of the lensed radio-quiet quasar HS0810+2554 after removing the effects of the lensing. Right: the data from the Karl G. Jansky Very Large Array showing what the source looks like after passage through the lensing galaxy. The images are not to scale – the lensed image appears to be many times larger in the sky than the actual size of the source. Credit: N Jackson/NRAO

Mini-jets of material ejected from a central supermassive black hole appear to be the culprits behind faint radio wave emissions in ‘radio-quiet’ quasars. A study of gravitationally-lensed images of 4 radio-quiet quasars has revealed the structure of these distant galaxies in unprecedented detail...

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Measuring the Shape of the Milky Way’s Black Hole

Measuring the shape of the Milky Way's black hole

This figure shows the locations of the radio telescopes linked together to observe the supermassive black hole at the center of our Milky Way. Credit: Ortiz-LeOn et al.

At the heart of our galaxy’s center is SagA*, a supermassive black hole containing ~4 million solar-masses of material. SgrA* is relatively faint, unlike the supermassive black holes in some other galaxies. This is probably because, unlike its active cousins, it is not aggressively accreting material and so is neither heating up its environment nor ejecting particularly intense jets of fast-moving charged particles. Of course, it is also faint because it is located about 25 000 light years from Earth and because it is shrouded in absorbing, intervening dust...

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