October 20, 2017

20.03.10: Spying a Black Hole Welterweight.

An Artist's conception of NGC 5408 X-1. (Credit: NASA).

An Artist's conception of NGC 5408 X-1. (Credit: NASA).


   Astronomers now have observational evidence for a missing class of black hole. Stellar mass black holes, those up to about 10 solar masses, are well known as the remnants of supernovae. Likewise for supermassive black holes of 10,000 solar masses or greater known to reside in the hearts of galaxies like our own. The “missing link” in astrophysics has been intermediate mass black holes, or those between 100 and 10,000 solar masses. Now, scientists at the Goddard Space Flight Center in Greenbelt Maryland have used the XMM-Newton and Swift X-ray satellites to pinpoint a likely candidate; NGC 5408 X-1, a black hole with about 1,000 to 9,000 solar masses in a galaxy about 15.8 million light years away in the constellation Centaurus. This would include an event horizon about 3,800 to 34,000 miles across. An X-ray flux occurs once every 115.5 days, strongly suggesting that NGC 5408 X-1 has a stellar companion accreting donor material. This star would be 3-5 times the Sun’s mass.   “Astronomers have been studying NGC 5408 X-1… because it’s one of the best candidates for an intermediate mass black hole.” States Philip Kaaret of the University of Iowa. The contributing companion also gives astronomers the unique opportunity to probe the near-space environment as well as study this intermediate class of enigmatic objects.

31.10.09:Daylight Saving Time: Is it Really Worth it?

Tomorrow, at 2AM, astronomers throughout North America can rejoice; daylight saving time (DST) ends for most areas that observe it in Canada and the U.S. as we revert back to ye ole’ standard time. This means observers will no longer have to undergo the long nightly process of sleep deprivation to await dark skies. Indeed, from northern tier states, it can be well past 10pm in mid-summer before its considerably dark! Ah….bring on the darkness. But this also brings up the following is issue….do we REALLY need daylight savings time at all? Allow us to approach the virtual soapbox, if you will. Daylight saving was first famously proposed by Benjamin Franklin and established in the US after World War I. Benefits sited at the time were energy conservation, as well as optimizing daylight hours to coincide with peak productivity periods. These days, public safety is also noted. In 2005, the Energy Policy Act was signed into law by president George W. Bush, rolling daylight saving back even further, currently spanning from the 2nd Sunday in March to the 1st Sunday in November. Granted, this may be way down some people’s lists of enduring offenses committed by the Bush administration, but the damage has been done. This year’s shift represents the earliest that we can potentially “fall back,” as November 1st is a Sunday. In agrarian times, this curious system might have made sense; each local hamlet set its own time, and primary reliance was on sunlight for human activities. But in a global, 24 hour civilization, is this idiosyncrasy for the past really required? Claims of energy savings are dubious; how about smarter night-time lighting policies? Some states, such as Arizona and parts of Indiana have done away with DST all together, and the Apocalypse has yet to rain down on them. In northern areas such as our native Maine and Alaska, DST is sort of a moot point, as the gathering winter darkness always ultimately wins. Let’s say “Down with DST,” in an effort to bring back sanity and our dark skies. Let’s step forward into the 21st century! Anyway, that’s our 2 cents…we here at Astroguyz would do away with all time-zones as well, but that’s another post…see you in Standard Time-land!


02.10.09: A Small Observatory Helps with a Big Discovery.

When it comes to cutting edge astronomy, many think of lofty mountaintop behemoths, such as Keck, or the orbiting Hubble Space Telescope. But how many of us think of… Gainesville, Florida? This article caught my eye this morning because its literally right in our backyard here at Astroguyz HQ in Hudson, Florida. As any would-be Floridian astronomer knows, the Sunshine State is not an optimal environment for astronomy, as humid, damp, East Coast conditions predominate. But that didn’t stop astronomers at the University of Florida in Gainesville from using the Rosemary Hill Observatory in nearby Bronson to help with observations of a transiting exoplanet; HD 80606b. 200 light-years distant, this hot-Jupiter is in an extremely eccentric orbit and was only recently realized to be a transiter, i.e. to occasionally pass in front of its host star as seen from Earth. Astronomers, however, were faced with a problem; the next transit was due occur June 4th of this year, when HD 80606b would be low in the twilight sky. This meant that observations of the eclipse could only occur over a short span from any given longitude. Enter U of F astronomers Ford, Reyes and Colon, who realized that Rosemary Hill might just be positioned to catch such an event. Located, as is most of Florida, at a scant 140 feet above sea level, Rosemary Hill may just qualify as the “lowest” observatory in the world. It sports 30” and 18” reflecting telescope(s), which are primarily used for education and training, as the U of F astronomers tend to travel to the “big guns” in the Canary Islands for “serious” research. The night of the 4th, however, Rosemary Hill showed its stuff; as a participating observatory in Massachusetts was clouded out, leaving the Gainesville astronomers as key to gathering data at their respective longitude. Colon noted that the experience of actually guiding the telescope and monitoring the star during transit was “definitely unique” and different from the remote observing now prevalent at larger observatories… the data gathered will go far towards understanding this bizarre exoplanet and its 111 day orbit. And the moral of the story is…every telescope can contribute, even your home town observatory!