September 21, 2017

A Messier Marathon.

M37 in Auriga. (Photo by Author).

Spring is deep sky season. As the weather becomes more temperate and the daylight/nighttime balance sits roughly equal worldwide, telescopes at star parties begin to sprout up like springtime daffodils. Now is the time to nab that obscure cluster, or attempt to spy that faint planetary nebula. We here at Astroguyz always try to spot one new object every observing session… but have you ever tried to see all the Messier objects… in one night? [Read more...]

Astro-Challenge of the Week: Can you Spot the Brightest Quasar?

(Credit: (NASA/CXC/SAO).

(Credit: (NASA/CXC/SAO).

The luminous jet of 3C 273 in X-rays.

   This week, we here at Astroguyz are going to show you how to go after that most elusive of beasts; a quasar. Even seasoned amateurs do not always realize that some of the brighter denizens of this elusive class of beasts are bag-able with a telescope of moderate-sized aperture. Of course, don’t expect to see much; part of the fun of this challenge is the fact you can see it at all, and the wonder of what the object actually is. Our visual prey is 3C 273 is the constellation Virgo. This object was the 273th listed in the 3rd Cambridge Catalog of radio sources, and at a 16% red-shift, stands at “only” about 2 billion light years distant! This also gives it an apparent recessional velocity of 30,000 miles per second. Visually, 3C 273 hovers at about magnitude +12.2, although it has been known to vary by about magnitude 0.5 in either direction. Its coordinates are;

Right Ascension: 12 Hours 29 minutes 6 seconds.

Declination: +02° 03’ 06” N

A good series of finder charts courtesy of the AAVSO may be had here; 3C 273 is about 4.7° NW of the star Gamma Virginis and very near the galaxy NGC 4536.

Now for the mind-blowing part; the absolute magnitude of 3C 273 is about -26; if this object was 10 parsecs distant, it would visually rival our own Sun! Its output also tops our own Milky Way galaxy by a factor of x100! As you can see, writing a post on the topic of quasars demands the extreme over-usage of exclamation points. 3C 273 is a worthy target for aperture 6” or greater, and stands as the farthest object you’ll probably ever lay eyes on. It also serves as a good reply to that common neophyte question heard at star parties; “So, how far can you see with that thing?” And just think, the light left 3C 273 when the Proterozoic era was the newest, greatest thing here on Earth… imaging may even help you grab this beast. Amateurs have even successfully recorded a spectrum of 3C 273 and measured its red-shift, a good reply next time someone asks you; “Yeah, but how do YOU know the universe is expanding?”  As the waning Moon slides out of the evening sky, I invite you add a quasar to your visual athlete-life list!

This week’s astro-word of the week is Quasar. Short for Quasi-Stellar object, this class of amazing objects was not even heard of until the early 1960s. Much controversy raged for decades as to exactly what astronomers were seeing; theories ranged from white holes to anti-matter fueled stars in the early universe. With the advent of accretion disc theory as a massive energy source outlined in the 1970’s a model of quasars slowly emerged; the consensus now is that we are seeing highly energetic galactic nuclei early in their youth. Perhaps the supermassive black hole at the core of our own Milky Way Galaxy was once a quasar itself, gobbling up interstellar matter and emitting massive amounts of x-rays and radio waves before settling down to the relatively placid state we see today. Other classes of objects such as blazars and radio galaxies have further filled in the classification gaps, and the massive amounts of energy we see in some quasars are thought to simply be the result of our viewing angle here on Earth. The brightest quasars devour perhaps 1000 solar masses of material a year, and the most distant recorded is CFHQS J2329-0301 discovered in 2007, with a red-shift of 6.43 and about 13 billion light years distant. This puts it in the realm of the very early universe, which is only 13.7 billion years old!

Review: Burnham’s Celestial Handbook.

A three volume classic! (Photo by Author).

A three volume classic! (Photo by Author).

A few decades back, I mentioned to a friend at a local planetarium of my enduring interest in astronomy. “Surely, then, “ he said pulling out a three volume set, “you have these…” I did not at the time, but I had indeed heard the legends. The books were Burnham’s Celestial Handbook, a three volume compendium on observational astronomy. A few weeks back we did a piece on the man, Robert Burnham Jr. and his tempestuous life; now I’d like to break with tradition a bit a provide a review of this indispensable astronomical classic. [Read more...]

29.9.9:Hubble Spies a Galactic Jet.

A fast moving jet from the core of M87. (Credit: NASA/HST).

A fast moving jet from the core of M87. (Credit: NASA/HST).

The formerly ailing Hubble Space Telescope spied something remarkable earlier this year; a rapidly expanding jet around the massive galaxy M87. Dubbed HST-1, this blob of matter is the first object with a Hubble designation, and has been tracked for over seven years. Brighter than the galaxies’ own core, the gas knot is 214 light years from the core and receding. M87 is visible in the constellation Virgo with a backyard telescope, and is part of the massive Virgo cluster of galaxies about 54 million light years away. The growth of the brightness of the jet expanded by 90 fold over the past decade, giving astronomers the opportunity to examine an active galactic nucleus in action. As the refurbished Hubble begins to strut its stuff, doubtless HST-1 will be an object of increased scrutiny!

Searching for Robert Burnham.

One of the very few existing pictures of Robert Burnham Jr. (Credit: The Robert burnham Jr. Memorial Project).

One of the very few existing pictures of Robert Burnham Jr. (Credit: The Robert burnham Jr. Memorial Project).

Sometimes, the quietest minds among us also have the most to share with the world.

Last month, on a warm summer’s day in August, the East Valley Astronomy Club, in connection with the Robert Burnham Jr. Memorial Fund, honored a man with the dedication of a small plaque placed on the Pluto walk at the Lowell Observatory. That man is probably the most unknown, but influential amateur astronomer of the 20th century; Robert Burnham Jr. a man that but for a singular colossal work, might have passed on into total obscurity. The book is Burnham’s Celestial Handbook, a three volume guide to the wonders of the night sky. [Read more...]