Report for 2001-09-21
Welcome to the Utah Skies Report.
Brought to you from beautiful Park City, "View-tah".
| Sunrise: 7:13 am | Sunset: 7:27 pm |
| Astronomical Twilight Ends: 5:41 am | Astronomical Twilight Begins: 9:00 pm |
| Moonrise: 12:09 pm | Moonset: 10:22 pm |
Star Party
| Utah Skies is welcoming the start of
autumn with our first star party of the season. Please join us under the
dark skies of Park City's Trailside Park
tomorrow night, Saturday September the 22nd from 8:00pm until 1:00am. Our
evening will begin with a tour of the solar system. First up will be views
of the crescent moon -- then we're off to meet several other
residents of our solar system. Mars, Jupiter, Saturn, Uranus, Neptune and
maybe even Pluto (if we can find it ;). Don't think for a moment that we'd limit our travels to the solar system. Nope! We'll journey throughout our galaxy and beyond. Star clusters, nebulas and even remote galaxies are all on our itinerary -- So, call your friends and plan on coming up to party with us! |
Viewing Outlook
| The weekend forecast is finally calling for
clear skies. Just in time for the star party :) I got some awesome viewing this past weekend at the Eagles Nest B&B down in Glendale. Located about 40 minutes north of Kanab in south central Utah, this area has some of the darkest and clearest skies on the planet. I saw details in the Andromeda Galaxy that I'd only seen in pictures! |
AURORA WATCH
| According to Spaceweather.com
- An M1-class solar flare exploded near sunspot 9620 on Sept. 18th and hurled a lopsided halo coronal mass ejection into space. The expanding cloud, although not squarely Earth-directed, will probably sweep past our planet late Thursday (9/20) or Friday (9/21). High-latitude sky watchers should remain alert for auroras around local midnight on both
dates. The accompanying image, captured by Canadian Dominic Cantin over Quebec, was not even expected. Let's hope that we get a nice display this weekend. Currently, the NOAA is setting the odds at 5% for severe and 35% for minor geomagnetic activity for observers at mid-northern latitudes. Let's keep our fingers crossed. |
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| The Hubble Space Telescope
has distinguished itself as the premier source of astronomical images.
Amazing HST images have graced the covers of major magazines and
newspapers worldwide. In recognition of the amazing advances in astronomy
and physics which have come from Hubble discoveries, we'd like to devote a
section of this report to share some of them with you. |
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| Planetary Nebula Mz3 According to the Hubble Heritage team, NASA's Hubble Space Telescope snapped this remarkable view of Planetary Nebula Mz3. Also known as the "Ant Nebula", this beautiful image reveals two distinct lobes emanating from the dying central star. Astronomers are wondering how a spherical star can produce such varied, non-spherical nebula. Hmmm.... I have no idea... but it sure looks awesome :) Actually, current thinking points towards the possibility of a closely orbiting companion star. This stars gravitational influence would alter the flow and direction of ejected gas. |
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Space Weather Update
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According to Spaceweather.com, "The solar wind blowing past Earth today (Tuesday) is thick and gusty. However, geomagnetic activity remains low. The interplanetary magnetic field (IMF) around our planet is pointing north -- a condition which strengthens our magnetic defenses against solar wind disturbances." As I write this report, I'm hoping for a nice earth-directed CME towards the end of the week followed by some serious mid-latitude auroral activity for Saturday nights Utah Skies Star Party. |
Lunar
Phase
| We'll be the first quarter moon this
weekend. This is probably the best time to observe the moon. As it
approaches the half illuminated point you can watch details unfold along
the terminator -- the region where dark meets light on the lunar surface. The
moon will be high in the south west when it gets dark -- setting well
before midnight. Go outside and check it out. I took the accompanying picture earlier this spring through a 10" f/4.5 reflector. The moon is an easy target to photograph. Virtually any camera will capture it. If you're shooting through a telescope, keep your exposure times very short and be sure to bracket the shot. Bracketing is a technique used by photographers where they shoot several pictures to cover a range of exposures. This way, their virtually assured of getting at least one good shot. |
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Planetary Report
| Mars is rising in the southeast around 3:35 pm. It will be high in the south-southwest by the time it gets dark. We're rapidly losing Mars. The Earth has pulled away from Mars in it's orbit causing Mars to shrink - it is currently down to a measly 11" from 21" in June. Once it gets below 10", we'll basically be unable to make out any surface detail. Additionally, it has dimmed significantly as well - currently shining at magnitude -0.51 down from -2.4 in June. Remember, each magnitude change is a factor of 2.5 so, a 2 magnitude change is 2.5 * 2.5 = 6.25 times dimmer than it's peak! Anyway...Mars reaches its Zenith, or highest point in the sky, around 8:00pm. Best views of the planet start as soon as you can find it. From my location, I lose Mars by around 10:15. So, I barely even get to view it under truly dark skies. I'm already thinking about it's return visit in the summer of 2003. On that visit, Mars will be closer to Earth than at any point in the last 10,000 years! It will also be better positioned for viewers in the northern hemisphere. |
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Saturn joins us now about
11:00pm. Look for Saturn in the
east-northeast. At magnitude -0.01,
Saturn has finally made it to a negative magnitude. It of course is brighter than any of the stars in that area of the sky. This
will increase significantly over the next few months. Also,
as the Earth nears Saturn in it's orbit, it continues to grow -- currently
at to 19". Saturn is considerably larger and will soon be brighter than Mars.
Get out there and checkout Saturn. In even the tiniest of telescopes, Saturn is impressive. Those big, beautiful rings will blow your mind. Last Tuesday morning brought some of the steadiest skies I've seen in a while to Park City. I got some views of Saturn that were sharp up to about 375x! Cassini's Division looked inky black as it split the ring. If you don't have access to a telescope, you'd better plan on attending the upcoming Utah Skies Star Party. You can be sure that there will be several telescopes pointed at Saturn from the moment it rises until we pack up later that night . The accompanying image of Saturn by the Nordic Optical Telescope clearly splits the rings and also shows details in the planets cloud tops. |
| Next, look for Jupiter rising around
12:55am. Jupiter is the king of the Planets. It is more massive than
all the other planets combined. Jupiter is currently shining at mag -2.18 and it
covers a whopping
37". That's almost twice the apparent size of Saturn and over 3 times that
of Mars.
I've mentioned this previously, but you have to check out the tools section of the Utah Skies website for a cool java applet which depicts the relative position of the four major moons. It's called JavaJup. Watching the orbits of these moons is fascinating. Their motion is quite apparent during an observing session. Transits and shadow transits are the most impressive events. See if you can follow a transiting moons across the surface of Jupiter. This is often more difficult than you'd think. The Earth's turbulent atmosphere often erases the fine detail required to witness these events. However, shadow transits are usually quite easy to view. The dark, inky black shadow of one of the moons typically stands out in stark contrast to the bright surface of Jupiter. The accompanying image taken as the Cassini Space
Craft headed for Saturn shows a view of Jupiter which we can never see
from Earth, a side view. Orbiting the Sun far beyond Earth, we can only
see the lit side of the planet. This view certainly gives us a different
perspective. Also, notice the tiny moon Io suspended out in front of giant
Jupiter.
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| Venus is the last to arrive on the scene, rising at about 5:00am. While not impressive telescopically, Venus is stunning to the naked eye. If you're outside prior to the sun rising, make sure to look to the east. You'll see an impressive lineup of planets. Venus will be the brightest, low in the east. Jupiter will be next brightest, considerably higher in the east. Saturn will be the dimmest of the three, but it will be almost overhead. |
| Our Constellation report is an easy way for people to
become familiar with the nighttime sky. We’ll discuss myths associated
with the various constellations as well as describing the numerous deep
sky objects residing in the area. No equipment is required to view the
constellations, though a star chart can be quite helpful. This ease of
observing makes constellations a natural place to begin your journey to
the stars.
This weekend we move on to the constellation Pegasus -- The Winged Horse. A large northern constellation included by Ptolemy in his list of 48 (c. AD 140). It is noted for the prominent square - the Square of Pegasus - formed by its three brightest stars and Alpha Andromedae (Alpheratz), all of which are second magnitude.
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Deep Sky Report
The focus of our efforts this week will be the deep sky objects of
Pegasus. To find Pegasus, look high and towards the east after sunset. It is the constellation to the north of
Aquarius, which we covered last
week.
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Let's start things off with a nice, big, beautiful Globular Cluster -- M15(mag6.3). This is a really cool globular. Then again, I think all globulars are cool :) Anyway. It's big, it's bright, and at least in the big scope, resolves deep into the core. M15 is one of the brightest globulars in northern skies. M15 looks like a pile of diamonds stacked on a black velvet background. Can you see any color variation among the stars? Estimates place it's distance at around 35,000-40,000 light years, with a diameter of about 130 light years. This globular is noticeably denser towards the core. M15 is rather easy to find. Just extend a line from Theta through Epsilon Pegasi about 1/2 the distance and you'll have found it. |
| Next up is the beautiful spiral galaxy NGC7331(mag9.5) . The accompanying Robert Gendler image displays an incredible amount of detail throughout the galaxy, even revealing several companion galaxies in the background. Notice the bright central region and the beautifully arching spiral arms. This is a "classic" spiral galaxy! |  |
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Next up is a fine example of a barred spiral galaxy, NGC7479(mag11). This beauty has a prominent central bulge with arms wrapped around it. Viewed almost face-on, this galaxy should be visible in instruments as small as 8". Ideally, you'd want 12" and dark skies to fully appreciate this object. |
| Moving on, we come to the edge-on spiral
galaxy NGC7814(mag10.45). This beauty should be fairly easy to spot in an
8". However, viewing the central dust lane is another story
altogether. Reports I've heard indicate that a 16" is required
to clearly identify this feature.
To find this object, start at Gamma Pegasi (the south-east corner) and move 2.5° WNW. This amazing shot of NGC7814 by Robert Gendler image clearly captures the galaxy and its dust lane. |
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Our final stop in Pegasus leads us to
this weeks Utah Skies Challenge Object, NGC 7320 -- better known as
Stephan's Quintet. With a visual magnitude of around 12.65, finding this
object is not for those who fear a challenge. Dark skies and larger
apertures are the preferred route. There is considerable debate as to weather these galaxies are gravitationally bound, or just located in a chance visual alignment. At a distance of roughly 12.9 Mpc (Mega Parsecs) or over 42 million light years, this galaxy cluster is quite remote. Remember, 1 light year is equal to over 6,000,000,000,000,000 (6 trillion miles). So...doing the math (correctly I hope:) places this object 252,000,000,000,000,000,000,000 miles away. Somebody please check my math. This many zeros is hard to look at, never mind read. Anyway... Enough of that. The deep sky obsessed among you fears no challenge. You'll be out there looking for this in your binoculars :) |
If you are able to find all of these objects, you may be one of the
few, the proud, the Deep Sky Obsessed.
E-mail your findings to DeepSkyObservations@UtahSkies.org.
Next Weeks Report
Next week, we'll continue our journey through the cosmos
and focus on the constellation Lacerta.
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Stay up to date on astronomical happenings by regularly
checking the Utah Skies website at http://www.UtahSkies.org
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