SpaceX has done it again! Earlier today (Thurs. Sept. 3rd), the company completed a second hop test with a Starship prototype. This time, it was the sixth iteration (SN6) that successfully made the 150-meter (~500 foot) flight at their launch facility near Boca Chica, Texas. This latest test has further validated the Starship design and the Raptor engine, two systems which Musk hopes will someday take humans to the Moon, to Mars, and beyond!
Artist rendering of a binary black hole. Credit: NASA
Quasars are some of the most powerful objects in the Universe. They were first discovered in the 1950s as bright radio sources coming from almost point-like objects. They were given the name quasi-stellar radio sources, or quasars for short. We now know that they are powered by supermassive black holes at the center of distant galaxies.
Think you know everything there is to know about the famous Canadarm, and the story of the Canadian space program? A new book out next month delves deep into the fascinating backstory of the Canadian Space Agency.
The book is Canadarm and Collaboration: How Canada’s Astronauts and Space Robots Explore New Worlds by Elizabeth Howell, out on October 20th, 2020 by ECW Press.
Advances in technology are having a profound impact on astronomy and astrophysics. At one end, we have advanced hardware like adaptive optics, coronographs, and spectrometers that allow for more light to be gathered from the cosmos. At the other end, we have improved software and machine learning algorithms that are allowing for the data to be analyzed and mined for valuable nuggets of information.
One area of research where this is proving to be invaluable is in the hunt for exoplanets and the search for life. At the University of Warwick, technicians recently developed an algorithm that was able to confirm the existence of 50 new exoplanets. When used to sort through archival data, this algorithm was able to sort through a sample of candidates and determine which were actual planets and which were false positives.
Artistic design of the super-Earth GJ 625 b and its star, GJ625 (Gliese 625). Credit: Gabriel Pérez/SMM (IAC)
In the past decade, the study of exoplanets has grown by leaps and bounds. At present, a total of 4,201 planets have been confirmed beyond the Solar System and another 5,481 candidates await confirmation. In the midst of all this, M-type red dwarf stars have become a focus of exoplanet research because they appear to be the most likely place where rocky (aka. Earth-like) planets can be found orbiting within the star’s habitable zone (HZ).
However, that does not mean that red dwarf stars are good candidates for hosting habitable planets. Take GJ 887, for example, one of the brightest M stars in the sky that has a system of two (possibly three) planets. In the past, this star was believed to be calm and stable, but new research by astronomers from Arizona State University has shown that GJ 887 might not be so calm as previously thought.
This illustration shows the location of the 43 quasars scientists used to probe Andromeda’s gaseous halo. These quasars—the very distant, brilliant cores of active galaxies powered by black holes—are scattered far behind the halo, allowing scientists to probe multiple regions. Looking through the immense halo at the quasars’ light, the team observed how this light is absorbed by the halo and how that absorption changes in different regions. By tracing the absorption of light coming from the background quasars, scientists are able to probe the halo’s material. Image Credit: NASA, ESA, and E. Wheatley (STScI)
It’s possible that you’ve seen the Andromeda galaxy (M31) without even realizing it. The massive spiral galaxy appears as a grey, spindle-shaped blob in the night sky, visible with the naked eye in the right conditions. It’s the nearest major galaxy to ours, and astronomers have studied it a lot.
Now astronomers have used the Hubble Space Telescope to map out Andromeda’s enormous halo of hot gas.
This illustration depicts a gas halo surrounding a quasar in the early Universe. The quasar, in orange, has two powerful jets and a supermassive black hole at its centre, which is surrounded by a dusty disc. The gas halo of glowing hydrogen gas is represented in blue. A team of astronomers surveyed 31 distant quasars, seeing them as they were more than 12.5 billion years ago, at a time when the Universe was still an infant, only about 870 million years old. They found that 12 quasars were surrounded by enormous gas reservoirs: halos of cool, dense hydrogen gas extending 100 000 light years from the central black holes and with billions of times the mass of the Sun. These gas stashes provide the perfect food source to sustain the growth of supermassive black holes in the early Universe.
It turns out you can teach an old dog new tricks. With a recent upgrade to a 50-year-old radio telescope, astronomers have spotted nearly a dozen of a rare class of quasars, ones capable of flickering in less than an hour.
Hubble Space Telescope image of supernova 1994D in galaxy NGC 4526.
An Ancient Voyage
Earth is on a journey…
While our planet orbits the Sun each year – a billion kilometers – our entire Solar System is drifting through the Milky Way Galaxy making one rotation every 225-250 million years (that means dinosaurs actually lived on the other side of the Galaxy!) Humanity has been on Earth for a small fraction of that journey, but parts of what we’ve missed is chronicled. It is written into the rock and life of our planet by the explosions of dying stars – supernova. Turns out supernovas write in radioactive ink called Iron-60.
The Crab Nebula is the remains of a Supernova which occurred about a thousand years ago and was visible on Earth recorded by ancient astronomers – C. NASA/ESA/Hubble
As the Sun travels through the Galaxy, so too do the hundreds of billions of other stars that comprise the Milky Way; all swirling and spiraling in varying directions. If you could time travel to a distant past, you’d look up and see an unfamiliar sky – different stars, different constellations, and sometimes the glow of a brilliant supernova. Stars explode in the Milky Way about once every fifty years. Given the immense size of the Galaxy at around 150,000 light years in diameter, the odds of one of those stars exploding in our backyard is low. But while supernova happen in the Galaxy twice a century, those in close proximity to Earth, within 400 light years, do happen once every few million years. And along Earth’s epic 4.5 billion-year journey, it appears that we’ve had close encounters with supernova several times. In fact, we seem to be travelling through the fallout cloud of supernovae right now.
While appearing as a delicate and light veil draped across the sky, this image from the NASA/ESA Hubble Space Telescope actually depicts a small section of the Cygnus supernova blast wave, located around 2600 light-years away. Credit:
ESA/Hubble & NASA, W. Blair.
If you’re a Star Trek fan, you may think the above image portrays the “Nexus” from the movie Star Trek: Generations. In the film, the Nexus was a ribbon-like extra-dimensional realm that exists outside of normal space-time.
But this is actually a real image from the venerable Hubble Space Telescope, of the Cygnus Loop. This stunning picture from space shows just a small portion of a blast wave left over from a supernova that took place, from our vantage point, in the northern constellation Cygnus the Swan.
Believe it or not there are some people out there who think traditional rocket science is too easy and want more of a challenge. A group at the University of Illinois (UI) decided to up the difficulty a bit by attempting to design a rocket engine that is capable of both electric and chemical propulsion.
Such a dual-mode rocket engine would have the benefits from both kinds of propulsion. The chemical side would give them significant thrust and quick reaction times when needed at the cost of efficiency, while the electric engine would allow for efficient, though slow, travel. Recently the group tested a novel type of rocket fuel that might just be able to be used in both types of engines.
