February 19, 2010 – The Space Shuttle Endeavour As Seen  from The ISS After Undocking. (NASA)

A Short History of Black Holes on Radio Telescopes

So, you’ve probably heard by now that we have our first ever photographs of a black hole and its event horizon. But it’s not like black holes have just been theoretical entities this entire time, awaiting photography’s blessing to finally be anointed as real. We’ve been detecting black holes for a long time now using radio telescopes and infrared cameras. It may be outside the visible spectrum, but that doesn’t mean it ain’t real, son!

The story begins in the mid-1900s when astronomers expanded their horizons beyond the very narrow range of wavelengths to which our eyes are sensitive. Very strong sources of radio waves were discovered and, when accurate positions were determined, many were found to be centered on distant galaxies. Shortly thereafter, radio antennas were linked together to greatly improve angular resolution. These new “interferometers” revealed a totally unexpected picture of the radio emission from galaxies–the radio waves did not appear to come from the galaxy itself, but from two huge “lobes” symmetrically placed about the galaxy….

Ultimately this led to the technique of Very Long Baseline Interferometry (VLBI), in which radio signals from antennas across the Earth are combined to obtain the angular resolution of a telescope the size of our planet! Radio images made from VLBI observations soon revealed that the sources at the centers of radio galaxies are “microscopic” by galaxy standards, even smaller than the distance between the sun and our nearest star.

When astronomers calculated the energy needed to power radio lobes they were astounded. It required 10 million stars to be “vaporized,” totally converting their mass to energy using Einstein’s famous equation E = mc2! Nuclear reactions, which power stars, cannot even convert 1 percent of a star’s mass to energy. So trying to explain the energy in radio lobes with nuclear power would require more than 1 billion stars, and these stars would have to live within the “microscopic” volume indicated by the VLBI observations. Because of these findings, astronomers began considering alternative energy sources: supermassive black holes.

We’ve also been tracing the orbits of planets, stars, and other objects that do give off conventional light. All this tracks back to suggest the supermassive black holes that Laplace et al first theorized about hundreds of years ago.

So, we knew what we were looking for. That’s how we were able to find it. And boom! Now we’ve got its photograph too. No more hiding from us, you goddamn light-devouring singularities. We’ve got your number.

The last shuttle

International Space Station flyover

Space cards

Mountains on the Moon (actually Pluto)

The last shuttle

Happy Earth Day

Image of Saturn taken by Cassini spacecraft in October 28, 2016.

Credit: NASA / JPL / Cassini

The Curiosity Rover Captures a 1.8 Gigapixel Panorama of Mars

Late last year, NASA’s Curiosity rover took over a thousand photos of the Martian landscape while exploring a mountainside. NASA stitched the photos together and recently released this 1.8 gigapixel panorama of Mars (along with a mere 650 megapixel panorama, pictured above). Here’s a version you can pan and zoom:

And a narrated video of the panorama:

Both panoramas showcase “Glen Torridon,” a region on the side of Mount Sharp that Curiosity is exploring. They were taken between Nov. 24 and Dec. 1, when the mission team was out for the Thanksgiving holiday. Sitting still with few tasks to do while awaiting the team to return and provide its next commands, the rover had a rare chance to image its surroundings from the same vantage point several days in a row.

I like how NASA is casually suggesting that the rover is just kinda taking some vacation snaps while waiting on friends.

LA-LA LAND-ING   The space shuttle Endeavour, perched atop a specially-modified NASA 747 jet, approaches Los Angeles International Airport last week.  The retired spacecraft will be towed to its new home at the California Science Center.  (Photo: Stephen Confer via NASA APOD)