What’s Up This Week – Jan 10 – Jan 16, 2005

Monday, January 10 – On this day in 1946, the US Army Signal Corps set an “astronomy first” by successfully bouncing radar waves off the Moon. Earlier today, the New Moon made its closest approach Earth (perigee) for this year – its gravitation favouring higher than normal tides – but tonight we will celebrate its absence by taking a celestial journey to the Eridanus/Fornax studies.

Starting with Alpha Fornacis, we find a beautiful disparate double, a “white” star with its yellow/orange companion. But this is not about doubles tonight – it is about deep sky – and Alpha is merely a stepping stone. Our next hop is to Beta, the guide to the NGC 1049 to the southwest. Only large aperture may reach for this one. The NGC 1049 appears to me as a very soft, very faded globular cluster. It is like a “ghost” – seen, yet not seen – an ethereal hint of what lay on the outer reaches of our own galaxy. Next stop is north, and slightly to the east for a galaxy revealed in both small and large scopes – the NGC 1097. In a small scope (114 mm minimum) it shows averted as an upright bar of light that pulls at the tips. The large scope (12.5″ and larger) will reveal a barred-spiral. The NGC 1097 is truly beautiful. The central portion of the galaxy is evenly illuminated from end to end, but at each of those ends lay the spiral arms, twisting away opposite of each other into space.

Next hop is Omega – again a double star – but much closer in magnitude this time! They can be separated easily enough with scopes at a minimum of power, but let’s head back for Alpha. Go north and a bit west into the border of Eridanus in search of NGC 1232. Smaller scopes can only make out of soft circle of light, while large ones reveal a spiral galaxy. It is not an exceptional one, but it contains a very “stellar” nucleus and fades out evenly towards its frontiers. Aversion plus magnification can only add just the most wispy of hints of a single spiral arm. From there, head for Tau 4, and a target you will repeat again and again! The NGC 1300 is an “all scopes” kind of galaxy and one you can appreciate. Smaller (114 mm) and mid-sized (150 mm) scopes will show a very bright core and transient arms upon aversion that remind me of a cat’s eye marble. Larger scopes can hold it direct, allowing for study of perhaps the finest barred-spiral I have ever encountered. Its nucleus is a bright point of light set within its structure, the “bar” itself being rather ephemeral and almost nebula-like in appearance. Two very well defined arms wrap round it, with mottled indications suggesting giant clusters of stars in this faraway island universe! A most fascinating galaxy…

Now back to Tau 4, and a shift north and a bit east to return to the “River”. NGC 1332 is our next stop, an elliptical galaxy. Just a silver oval in the small scope, and not overly improved by aperture. With the additional light gathering ability, the NGC 1332 now contains a much brighter nucleus, and very even form. Let’s go south back down into “the Furnace” and breathe the scopes east to capture planetary nebula NGC 1360. Say hello to a ball of greenish light in a small scope and go for aperture. Now we’re talking! The planetary now stretches itself out and reveals a bright, almost distracting inner star. When you can peel your concentration away from it, averted vision reveals a certain vagueness – almost a transparency – inside one very kicking planetary! Just a touch southwest of here brings up yet another bright barred-spiral, the NGC 1398. Once again, we’re looking at easily distinguishable in most scopes, but what intrigues me is WHY does this area of the sky contain so many barred spirals?! What “string” resonates in the vast reaches of space that spawns this structure?!

As the radio plays music in the night keeping us company, shall I take you on a radio journey? Let’s go to Chi 1 ,2, 3 and drop southwest for the NGC 1316. Hey up! Just another elliptical, right? Wrong. The NGC 1316 is THE radio source for Fornax A. (i wonder if it does rock and roll? 😉 The little oval smear of light shows well averted in small scopes, but aperture brings up a bonus! Just a tiny bit north of “the Source” lies a companion known the NGC 1317! Let’s hop back to the Chi triangle, and go for yet another. A degree east will bring up the NGC 1365 – “lightning” frozen in the form of a barred-spiral galaxy. There are no “hints” in form here. This 11th magnitude galaxy shows well in mid-aperture, with aversion in small and will come alive in larger scopes. The central core is Z-shaped, very definite and bright. The central bar continues to hold up to direct vision, bracketed by two arms that differ. One tends to diffuse away a bit, but the other holds a very solid brightness.

Large scopes? Come with me, and be thankful that our feet are upon the ground. I am going to take you to a galaxy playground in this region – one degree northeast of NGC 1365. Using a mid-sized scope, in this new “field” you will see two ellipticals, the NGC 1399, and the NGC 1404. For experienced galaxy hunters, you know how to play this game. Look directly at those galaxies, yet “feel” the field with your eyes. Ah, you see it! Now let’s put the power of aperture to work and watch them dance! With a quality wide-field eyepiece in a 12.5″ telescope, the Fornax Galaxy cluster is stunning. How many do you see in one degree? Nine? When you touch the scope, how many in the relative field? Twelve? Fifteen? Yes, of course some of them we’ve already visited. The tightest portion of the cluster also has designations: NGC 1374, NGC 1379, NGC 1380, NGC 1381, NGC 1387, NGC 1399, NGC 1404, NGC 1386 and NGC 1389. They will be tiny and faint, but very beautiful. You can see now why we have taken so much time to study Eridanus. It shares its soul with Fornax.

And tonight it has shared with us…

Tuesday, January 11 – Over the next two days, be sure to set your alarm for approximately 45 minutes before local sunrise to witness Mercury and Venus slow dancing on the horizon! At approximately 0.3 degrees apart, this wonderful union will be quite low (about a half fist above the horizon), but SkyWatchers will appreciate watching as the pair seems to “trade places” in the morning sky. How long can you follow them from your location?

Tonight the tender crescent of the one-day old Moon will create a similar challenge as it makes its appearance at dusk on the western horizon. Thankfully it will have set long before skies get truly dark, giving deep sky hunters an additional night to continue studies!

Wednesday, January 12 – Tonight we will greet the “Old Moon In The New Moon’s Arms” as the two-day old Selene will make a brief appearance after sunset to the west. The origins of this romantic phrase are very apropos, for many shadowy details of the full Moon are softly visible thanks to reflected sunlight from our atmosphere known as “Earthshine”. For those viewing with either telescopes of binoculars tonight, take the time to study the emerging Mare Crisium. Crisium is a unique for it does not connect with other maria and is seen on the curved limb. Viewing an area like Crisium on a curvature makes its dimensions appear smaller than they truly are. In terms of true size, Mare Crisium has about the same area as the state of Washington, yet appears visually to be only about half that size!

For Southern Hemisphere viewers, Comet C/2003 K4 (LINEAR) will be a splendid target for binoculars and small telescopes at around magnitude 7.8. On the night of January 12, it will be very close to Lambda Pictor.

Thursday, January 13 – Today Saturn reaches opposition, (my how a year flies when you’re having fun! 😉 In astronomical terms, this means that Saturn and the Sun are on opposite sides of the sky. Opposition also means that not only is Saturn closer than normal, but it will be visible all night long. Take the time tonight to watch as the Sun sets and notice its departure to the southwest – Saturn will rise at precisely the same angle to the northeast!

Tonight, let’s wait for the Moon to get as far west as possible and set our sites about halfway between Theta Auriga and El Nath. Our study object will be open cluster, M37! Apparently discovered by Messier himself in 1764, this galactic cluster will appear almost nebula-like to binoculars and very small telescopes – but comes to perfect resolution with larger instruments.

At around 4700 light years away, and spanning a massive 25 light years, the M37 is often billed as the finest of the three Aurigan opens for bigger scopes. Offering beautiful resolvability, this one contains around 150 members down to magnitude 12, and has an estimated population in excess of 500. What makes it unique? As you view, you will note the presence of several “red giants”. For the most part, open clusters are usually comprised of stars that are all about the same “age”, but the brightest star in the M37 appears orange in color and not blue! So what exactly is going on in here? Apparently some of these big, bright stars have evolved much faster – consuming their fuel at an incredible rate. Other stars in this cluster are still quite young in the cosmological scale, yet they all left the “nursery” at the same time! In theory, this allows us to judge the relative age of open clusters. For example, M36 is around 30 million years old and the M38 about 40, but the presence of the “red giants” in the M37 puts its estimated age at 150 million years! Just awesome…

Friday, January 14 –
Happy New Year to those who follow the Julian calendar! Today begins the year 2758 AUC and tonight we will celebrate antiquity by studying two craters on the Moon named for mythological figures – Atlas and Hercules.

Easily identified on the terminator in the northern hemisphere, this pair of craters can be spotted in binoculars and offer a wealth of detail to the small telescope. The smaller one to the west is Atlas and the larger to the east is Hercules. Because they are near the terminator tonight, their differences in depth make for a fascinating contrast in illumination. Note Hercules’ bright west wall – it is so deep that the interior is literally hidden in shadow! Atlas, only under slightly higher “sunrise”, will show the majority of grey floor with a boundary of dark shadows on its east wall and a brilliant west crest. Sharp-eyed observers may note a “Y” shaped rimae in Atlas’ interior with a small central peak caught in its intersection. Wishing you steady skies!

Saturday, January 15 – Ready for another weekend treat? Then realize for the next two nights, the “Magnificent Machholz” will race closely past a previous study star – Algol!

As we remember, Algol is a fascinating variable and for most of us it will be at minima (magnitude 3.4) tonight. Using our binoculars, we will find the 4th magnitude Comet Machholz about 2 degrees to the lower right of the “Demon Star”. Although the Moon will hamper tracing the tail for most, try de-focusing and comparing magnitudes. The fun is about to begin! If skies permit, return again tomorrow to the Machholz/Algol pairing – Beta Persi has now jumped to a magnitude brighter and the comet has moved even closer and to its lower left!

Hey, now… Astronomy doesn’t get much more exciting than that!

Sunday, January 16 – Wake up! Early this morning will be the peak of Delta Cancrid meteor shower. Yes, it’s a pretty obscure one – no exciting parent comet or disintegrating asteroid to blame it on – but since the Moon will long be set, why not give it a go? The radiant will be just slightly west of the M44 “Beehive Cluster”, making a worthy trip with binoculars. The Delta Cancrids are not exactly prolific – with a rate of only about 4 per hour – but they are very fast!

Ad speaking of fast, Mercury is now below Venus and gradually pulling away. Our planetary “pair” are now separated by 0.7 of a degree this morning and will part by almost a full degree tomorrow morning. Only SkyWatchers with an open horizon to the east will be able to catch them, because they are barely 2 degrees above the horizon before dawn. Enjoy them one last time for they are about to disappear!

Is it back yet? Yes. The Moon will definitely figure prominently in the coming days, but don’t be discouraged. The first few days of this week will see it set in ample time to enjoy deep sky studies, search out bright objects and continue to enjoy the swift progress of Comet Machholz! I hope I have challenged veteran observers and inspired those “new to the game” to seek out the beauty of our Cosmos. Until next week? I thank you for your many kind comments! I might be clouded out, but your words are as welcome as a clear night. So ask for the Moon, my friends… But keep on reaching for the stars!

Light Speed… ~Tammy Plotner