Explore $829.99 CELESTRON REMEMBER Scientific THE GOLDEN FirstLight Meade ETX125 OBSERVER 100 MAKSUTOV-CASSEGRAIN RULE: Maksutov- Cassegrain The ETX125 is perfect for aspiring astroimagers. Using Never buy a telescope the attached camera, one can look through an eye- based on magnification. Mounted on the Twilight piece, using the built-in star diagonal, and then quickly Nano Mount, this com- flip the mirror out of the way to take a photo. You can make any pact 3.9-inch (10 cm) telescope operate Maksutov telescope is SPECIFICATIONS Focal length: 1900mm at any magnification ideal for anyone who Focal ratio: f/5 just by changing needs to carry their Price: $829.99 Eyepieces: 9.7mm telescope down a flight Mount: equatorial dual- (196x) and 26mm (73x) the eyepiece. of stairs or is short on fork Weight: 25 pounds storage space. The Aperture: 5 inches (11 kg) Which telescope is best? That scope also comes with (12.7 cm) depends so much on you, your an eyepiece and a red- expectations, and your budget. But dot finder. in my experience, the best telescope doesn’t have to be the biggest or the SPECIFICATIONS most expensive. The best telescope is one that is used often and Price: $399.99 enjoyed by its owner! Mount: German equatorial Phil Harrington is a longtime Aperture: 3.9 inches contributor to Astronomy. He received (10 cm) the Walter Scott Houston Award at Focal length: 1400mm Stellafane 2018 for his lifelong work Focal ratio: f/14 promoting and teaching astronomy. Eyepieces: 25mm (200x) Weight: 4 pounds And for younger amateur (1.8 kg) astronomers looking to get their first scope, Celestron $1,599 check out Astronomy’s NexStar 8SE April 2021 story “The best CELESTRON scopes for kids.” The NexStar 8SE features the legendary Celestron 8 Scan the QR telescope on a one-armed, code to read computer-controlled mount the story online. that automatically locates and tracks objects selected from WWW.ASTRONOMY.COM 51 the onboard database. It comes with a red-dot finder, a 25mm eyepiece, and a star diagonal. SPECIFICATIONS Price: $1,599.00 Mount: altitude-azimuth Aperture: 8 inches (20.3 cm) Focal length: 2032mm Focal ratio: f/10 Eyepieces: 25mm (81x) Weight: 24 pounds (10.9 kg)
Star clusters and DRACO 50° galaxies will keep you looking at Hercules Vega NGC 6229 o LY R A fp all night long. k q BY MICHAEL E. BAKICH M92 m MAP SYMBOLS THE CONSTELLATION r HERCULES (pronounced HER-cue- Globular cluster 40° Planetary nebula leez) is one of the original star figures Galaxy l/ NGC d CORONA created by the Greeks, who called the e 6207 M13 BOREALIS hero Herakles. The main part of the pat- tern is reasonably easy to find. It’s visible HERCULES from mid-spring through mid-fall in the Northern Hemisphere. Its center lies at i¡ c R.A. 17h21m and Dec. 27°30'. 30° Hercules ranks fifth in size out of the 88 constellations, covering 1,225.15 j square degrees (2.97 percent) of the sky. + And while its size places it near the top of that category, it fares worse (48th) in hb NGC 6210 terms of overall brightness. 95 ` Abell 20° The best date to see Hercules is a 2151 June 13, when it stands opposite the Sun in the sky and reaches its highest point Rasalgethi g at local midnight. The constellation is t completely visible from latitudes north of 39° south and totally invisible only 10° ASTRONOMY: ROEN KELLY south of latitude 86° south. 19h 18h 17h 16h Although this star pattern isn’t OPHIUCHUS bright, it contains two Messier objects, both globular clusters: M13 and M92. The Hercules Galaxy Cluster (Abell 2151) lies at the The Hercules Cluster (M13) is the standout deep-sky You’ll find lots of other worthy targets, astounding distance of 500 million light-years from treat in this constellation. It glows at magnitude 5.8 too. Let your telescope adjust to the Earth. Abell 2151 requires at least a 12-inch telescope and has a diameter of 24'. Under a dark sky, you’ll outside temperature, get comfortable, and eyepieces that give powers in excess of 250x. spot it with your naked eyes two-thirds of the way and spend an enjoyable night leisurely Target its brightest member, the elliptical galaxy from Zeta (ζ) to Eta (η) Herculis. Through 8-inch making your way through the many NGC 6041, which glows at magnitude 13.4. and larger scopes, you’ll see hundreds of stars. great deep-sky objects residing in Hercules. Good luck! KEN CRAWFORD ADAM BLOCK/MOUNT LEMMON SKYCENTER/UNIVERSITY OF ARIZONA Michael E. Bakich is a contributing editor of Astronomy who enjoys slowly moving his telescope through a single constellation. 52 ASTRONOMY • JUNE 202 2
Once you’ve found M13, look ever-so-slightly less The Turtle Nebula (NGC 6210) is a planetary nebula Globular cluster NGC 6229 glows at magnitude 9.4 than 0.5° northeast for spiral galaxy NGC 6207. that measures 14\" across. But even through a small and measures 4.5' across. At low to medium Many low-power eyepieces show both objects in telescope, you can easily identify this planetary’s magnifications, you’ll see a nice triangle formed by the same field of view. Through an 8-inch telescope, light blue-green, turtle-shaped, magnitude 8.8 disk. the cluster and two 8th-magnitude stars. NGC 6229 you’ll see a magnitude 11.6 oval a bit more than Its high surface brightness lets you really crank up is 100,000 light-years away, so an 8-inch scope twice as long as it is wide. DIETMAR HAGER the magnification. CHRIS SCHUR shows just an unresolved glow with an irregular outline. MARTIN C. GERMANO Rasalgethi (Alpha [α] Herculis) is a binary that Globular cluster M92 is this constellation’s other The stellar pair called 95 Herculis lies in a no-man’s combines stars with magnitudes of 3.5 and 5.4. Messier object. It has a diameter of 14' and a land where few bright stars abound. One way to They’re separated by 4.6\". Because of a wonderful magnitude of 6.5. Nearly as bright as M13, M92 locate it is to look a bit more than 13° northeast of contrast effect, the secondary appears olive-green. easily resolves with small telescopes. Through an Rasalgethi. The (barely) brighter of these two stars The brighter primary is yellow with a trace of 8-inch scope, the core appears concentrated and (magnitude 5.0) glows yellow, and its companion orange. JEREMY PEREZ huge, surrounded by an outer halo of myriad faint (magnitude 5.1) is white. JEREMY PEREZ stars. BOB FERA WWW.ASTRONOMY.COM 53
The CMOS revolution is here A new type of camera may signal the future of astroimaging. BY TONY HALLAS T HERE WAS A TIME, heavy and a pain to transport. If you had no idea — until you developed the possibly before some of you were using a Newtonian reflector, you film — if you were making a mistake. reading this were born, when would be standing on a ladder for hours More than half the results would show astroimaging was an ordeal. watching the guide star. Often, after trailed stars or that everything was out Imagine a world with manual about 30 minutes, the eyepiece’s position of focus. Such was astroimaging when I guiding. You’d spend hours would place you uncomfortably between started about 35 years ago. The average staring at a star centered in an the rungs of the ladder and you would be “lifespan” of an imager back then was illuminated reticle until your eye stuck in this death crouch, clinging to three to five years. After that, most peo- teared up or you passed out into the ladder in the freezing cold, trying to ple couldn’t take it anymore. the eyepiece from fatigue. keep the star centered on the crosshairs. The equipment was also In the coming years, the Santa As if this wasn’t bad enough, you also Barbara Instrument Group produced the 54 ASTRONOMY • JUNE 2022
ABOVE: Emission nebula NGC 281 in Cassiopeia shows lots of detail in this image taken through R, G, B, Hydrogen-alpha, and Oxygen-III filters. TONY HALLAS first autoguider that actually worked: the certainly no match for FAR LEFT: QHYCCD’s images were being made SBIG ST-4. It immediately changed new camera, the QHY everything. Imagers could digitize film 600, incorporates a full- using a scanner and then process the frame CMOS chip that image on a computer using an early (and produces 61-megapixel now considered crude) version of images. QHYCCD Photoshop. After that, the first CCD (charge-coupled device) cameras became hypered — sensitized by that were not possible just a available. They were tiny things, some smaller than a postage stamp. a gas — large-format film year before, and amateur At first, CCD images were a curiosity, images exposed through superb tele- astronomers were capturing new details scopes. But little by little, CCD technol- on familiar objects for the first time. ogy improved. What finally elevated it Soon after the CCD appeared, another above film was its quantum efficiency. new detector arrived: the CMOS, short With film, you were lucky if it for complementary metal-oxide semicon- recorded 3 to 5 percent of the light that ductor. Unlike a CCD, where data is fell on it. With a CCD, that number bal- downloaded in rows and read at the edge looned to over 50 percent. Suddenly, of the chip, a CMOS chip reads every WWW.ASTRONOMY.COM 55
pixel at its position. It does this with with photoreceptors. This Four 10-minute shots engineering, including spe- transistors surrounding each photosensi- means that all incoming through R, G, and B cialties in noise reduction tive pixel. Initially, this created two photons strike the pixels. filters allowed the QHY as it appears in hardware problems. First, the transistors took up 600 to produce this real estate where more pixels could go; image of the Orion second, after a certain level of exposure, Nebula (M42). TONY HALLAS amplifier glow fogged the image. Back-illuminated chips and software — quite use- But CMOS chips were easier to make and thus less expensive. They also also increased the deep well capacity — ful when designing astronomy cameras. required considerably less power to run. In addition, CMOS chips have signifi- how many photons can be recorded The QHY 600 camera utilizes the lat- cantly higher frame rates, allowing users to take successive images faster because before the photo receptor site “fills up” est Sony IMX 455 CMOS BSI chip. (BSI the readout is quicker. Manufacturers kept improving CMOS chips until they and can’t record any more data. The stands for backside illuminated.) The had lower noise and higher resolution than their CCD counterparts. Sony Corporation accomplished much of pixel size is 3.76 microns. In the full With the advent of commercially this progress and most of today’s high- 35mm frame, this creates an image available back-illuminated chips, sensi- tivity and quantum efficiency skyrock- end CMOS astronomy cameras contain that is 9576x6388 pixels in resolution, eted. In such a chip, all the electronics are grouped behind the pixels, allowing Sony chips. or 61 megapixels in size. That pairs all the space facing the sky to be filled In fact, many manufacturers have nicely with wide-field telescopes like ceased to make CCDs. small refractors. Enter the QHY 600 The camera can also be binned 2x2 (where four pixels are combined to act as The QHY600PH mono CMOS chip one) for approximately 7-micron pixels camera that I am currently using is and lower file size. I do this when I use the beneficiary of all this history and my Planewave CDK17, which has a focal technology. It is the brainchild of Qiu length of 3,000mm and matches well Hongyun, more commonly known as Dr. with 7-micron pixels. Qiu, who founded QHYCCD in 2003. Dr. The QHY 600 mono camera works Qiu has degrees in optical science and well with the QHY CFW3 medium filter wheel, which attaches to the camera and plugs into it. The wheel is threaded for 2\" mounted filters and the openings are 50.8mm. If you use 50.0mm filters like those from Chroma, you’ll need spacers 56 ASTRONOMY • JUNE 202 2
to fill in the small gap. Several are avail- amplifier glow even with extended expo- producing the final results. I use MaxIm DL for my initial processing: the creation able online and work well. sure times. of master darks, flats, and bias frames. I also use it to reduce and combine all my The IMX 455 CMOS chip is the first Dew, condensation, and reflections data files. I find that the sigma combine function works great to maintain as to capture data in true 16 bits. Most cam- have always been problems with digital much information as possible and still remove outliers like hot pixels. Be careful eras use chips that capture data in 14 bits cameras. The QHY 600 addresses them with these. Some hot pixels change value so that the dark frame does not remove and interpolate up to 16 bits. True 16-bit with a desiccant plug for the hermetically them completely. You need outlier rejec- tion and at least five frames to affect data has an incredible number of tonal sealed CMOS chamber, high-end anti- their removal. values so stretching can be performed reflective coatings on all glass surfaces, After creating the master files, I save them as a 16-bit TIFF file. I then import without the image falling apart. By cap- and a heater to keep external windows it into Photoshop, stretching it with curves or levels to bring out all the detail. turing in 16 bits, you have the full range moisture-free. The sensor is cooled by a CMOS data have such low noise that cer- tain plug-ins work wonders. These typi- of 65535 density levels, which allows you regulated two-stage thermocouple device cally are Luminar, Topaz II, and the real secret weapon, the sharplet filter in the to pull out more detail during process- to maintain a constant temperature. Redfield suite. There are numerous star reduction methods, which include Russ ing. If you’re simply stretching 8-bit data, Croman’s Star Shrink and the minimum filter in Photoshop. In all cases, I use it doesn’t look good because of the lim- Creating images these powerful tools with the stars selected and feathered. ited number of tonal values. I try to keep my processing as simple Large stars can be reduced using the The QHY 600 is available in both as possible, yet I sacrifice nothing in liquefy filter and choosing the pucker tool. If it sounds like there are a lot of mono and color versions, and in a variety tricks to make striking images, you’re right. But the challenge can be part of of configurations depending on how you the fun. plan to use the camera. I spoke at length If noise does show up in your image, it’s usually in the shadows. Make a dupli- about shooting color versus mono in my PRODUCT cate layer, generously apply the noise review of the QHY 410C color camera, INFORMATION which appeared in the February issue. To sum it up, traditionalists like myself QHY600PH prefer shooting mono with separate fil- ters for the RGB and narrow bands. Sensor: Sony IMX455 back-illuminated It does get a bit more complicated, Sensor size: 36mm x 24mm (full frame) Image buffer: 2 gigabytes however. A color camera records all Pixel size: 3.76x3.76 micrometers colors simultaneously utilizing a Bayer matrix. This makes creating colored Effective pixel area: 9576x6388 images a lot easier and can be an advan- Output: 16-bit with 65535 levels tage for imaging certain objects, like Exposure range: 40ms to 3600s comets. If you are used to working with Computer interface: USB 3.0 a mono CCD camera, the switch to a Weight: 30 ounces (850 grams) CMOS mono camera should not be Dimensions: 5.2 x 3.5 inches difficult. (131.8mm x 90mm) The one difference that I have found Price: $4,599 between the two is that because CMOS has such low noise, you only need RGB exposures to create an image, with no luminance exposure required. If you feel you do need a luminance, you can fabri- cate one by averaging all the color data. Due to the large size of the files and the fast download speeds, QHYCCD built in a 2-gigabyte DDR3 The optional filter image buffer to smooth holder is seen here, data transfer to the host attached to the computer. The data QHY 600. QHYCCD from the QHY 600, in addition to its real 16-bit depth, are also true raw data, meaning the recorded data have undergone no adjustments, such as noise suppression or hot pixel removal. It is the original signal, which can be processed and manipulated as the situation necessitates. The camera has one other great feature: There’s zero WWW.ASTRONOMY.COM 57
filter, then use a mask The author created this are stuck with whatever gain, parts of your image can block up more image of the spiral NGC 2403 in Camelopardalis with the QHY 600, exposing through L, R, G, B, and Hydrogen- alpha filters. TONY HALLAS paint where the noise or sensitivity, is built into the easily, becoming pure white with no reduction should be camera. With a CMOS cam- detail in them. applied. You can adjust the overall power era, you can adjust the gain, similar to On a target like a faint galaxy, increas- of the noise reduction by adjusting the setting the ISO on your digital camera. ing the gain might be useful. I would opacity of the layer. Be aware, however, that as you raise the combine a medium increase in gain with One of the great differences between gain you forfeit some deep well capacity. 20-minute exposures to max out CCD and CMOS is that with a CCD, you This means that your stars and bright recorded detail. I would also take a few much shorter exposures to keep all the stars colorful without washing them out. These can be added to the final image to replace the blown-out stars produced by the increased gain. My conversion to CMOS is an ongo- ing learning experience. The QHY 600 is a good example of what is possible today. It is a versatile camera that is at home on many scopes, from a refractor to a Cassegrain reflector. I look forward to creating NGC 206 is a star- many excellent images forming region in the with it. Andromeda Galaxy (M31). The author created this Tony Hallas is a image by combining contributing editor of exposures through R, G, Astronomy and one of this B, and Hydrogen-alpha filters. TONY HALLAS planet’s finest astroimagers. 58 ASTRONOMY • JUNE 202 2
NEW S AT U R N GLOBE from Astronomy magazine! As a Space & Beyond Box subscriber, you get access to exclusive SURGXFWUHOHDVHV2QO\\DYDLODEOHDW0\\6FLHQFH6KRSFRPWKLVȴUVWHYHU 6-inch Saturn Globe is essential for any astronomy enthusiast’s collection! • Custom-produced, injection molded globe - Compilation of images from Cassini-Huygens space probe and Voyager 2 VSDFHFUDIWPLVVLRQV3OXVLQFOXGHVIHDWXUHVLGHQWLȴHGDQG labeled. • Detachable acrylic rings – Images created by Astronomy art department using NASA photography. Plus, includes 7 ring UHJLRQVLGHQWLȴHGDQGODEHOHG • Bonus – Detailed information guide with fun facts about Saturn, the images, and the globe’s production. Order your exclusive, limited-edition globe at MyScienceShop.com/SaturnGlobe 6-Inch Saturn Globe with Rings is expected to arrive in July 2022. Some assembly required. Sales tax where applicable. P40066 CAN’T MISS EXCLUSIVES! These products are perfect for anyone who enjoys viewing the night sky. Shop AstronomyJOREHVSRVWHUVSX]]OHVPXJVȵDVKFDUGVPRGHOVDQGPRUH Shop now at: 1000 OVER MyScienceShop.com PRODUCTS! INCLUDING EXCLUSIVES Sales tax where applicable. FROM ASTRONOMY P39484 WWW.ASTRONOMY.COM 59
SECRET SKY A total eclipse images from eclipse enthusiast Larry Shore of Mesa, rarity This ghostly white prominence dazzled Arizona, who experienced totality at the Antarctic Logistics and Expeditions camp on Union Glacier with viewers in Antarctica and online. the TravelQuest tour. The white feature was in his images as well, confirming the reality of this fiery ghost. White hot plasma Petr Horálek, a Czech astrophotographer who observed the eclipse from an altitude of 41,000 feet (12,500 meters) aboard a Boeing 787-8 Dreamliner, wrote on his website that the solar corona was “truly ‘wild,’ espe- cially on its left part,” where “hot plasma was visible to the unaided eyes.” The plasma came from an active region on the solar limb, “which itself was enough to be visible as a very bright ‘pearl’ above the eclipsed Sun.” Horálek directed me to images from the NASA Solar Dynamics Orbiter and the ESA Solar and Heliospheric Observatory. They show the active region at the white feature’s position and, above it, what appear to be loops ABOVE LEFT: A white illuminated by hot plasma flowing along magnetic field solar phenomenon appeared on the left Technology is amazing. Take the sharing of lines. limb of the Sun, seen here moments into the Dec. 4, 2021, total solar eclipse. The event The Sun’s active regions mainly consist of closed totality, with rich pink prominences visible occurred over a remote stretch of Antarctica magnetic loops, in which plasma is confined and glows at upper right. and its surrounding seas, allowing a limited travel audi- brightly. Horálek notes, however, that the Sun experi- SCREENSHOTS FROM VIDEO BY THEO BORIS AND CHRISTIAN ence. But thanks to the efforts of Theo Boris and enced small flares in the hours before the eclipse that LOCKWOOD OF THE JM PASACHOFF ANTARCTIC EXPEDITION/NASA Christian Lockwood of the JM Pasachoff lasted throughout the event. While the gas in ABOVE RIGHT: The 2021 Antarctic Expedition, untold numbers the Sun’s corona normally has a temperature hot plasma feature is visible in this extreme of viewers got to experience it live by stream- of a few million degrees, solar flare tempera- ultraviolet image taken by NASA’s Solar ing their eclipse feed on www.nasa.gov/live tures can range between 18 million and Dynamics Observatory. and YouTube from Union Glacier, Antarctica. 36 million degrees Fahrenheit (10 million NASA My wife Deborah Carter and I were among and 20 million degrees Celsius). This may be CENTER: Faint chromospheric them, and we were grateful for it — especially why, during the eclipse, the hot plasma in the activity is visible at the base of the white as an unusual eclipse phenomenon occurred. magnetic loops appeared so much more feature in this image taken from Antarctica. A fiery ghost What’s intense than the surrounding corona. astounding What’s astounding is the rarity of catching LARRY SHORE What caught our attention was the sudden is the rarity appearance of what at first looked like a such an event on the Sun’s limb during the BY STEPHEN white solar prominence on the Sun’s left limb brief moments of totality — especially given JAMES O’MEARA that the Sun is just emerging from its latest Stephen is a globe- trotting observer who in the moments before second contact (the of catching minimum and active regions still remain is always looking beginning of totality). The feature material- such an relatively sparse. Horálek says that there may for the next great ized from the solar glare just as Baily’s beads be a higher chance of catching a similar event celestial event. began to mix with pink jewels from the Sun’s event during during the 2023, 2024, 2026 (and maybe chromosphere. Then, after the diamond ring the brief 2027) total solar eclipses, when solar activity flashed into view, an arched prominence, moments of will be closer to its peak. rich pink in color, blossomed next to the totality. Thanks to the JM Pasachoff Antarctic diamond. Seeing that deep pink color only Expedition livestream, eclipse lovers the enhanced the striking white feature. world over got to witness a rare total solar After less than a minute of totality, the eclipse event from the comfort of home. But limb of the Sun emerged and consumed the white mys- if you were one of the lucky few who viewed the eclipse tery feature. Throughout totality, no other phenomenon from Antarctica and got to view the feature through matched its intensity, which was much brighter than binoculars or a telescope, I’d love to hear your visual the surrounding corona. I wondered if the white feature impressions at [email protected]. was an artifact of the live transmission, but Zev Hoover of the Pasachoff Expedition assured me it was not. BROWSE THE “SECRET SKY” ARCHIVE AT A couple of days later, Deborah received a series of www.Astronomy.com/OMeara 60 ASTRONOMY • JUNE 2022
NEW PRODUCTS Attention, Intro to cosmology Understanding Journey through manufacturers: the universe the solar system To submit a product Belknap Press for this page, Dutton Springer email products@ Cambridge, Massachusetts astronomy.com. New York City, New York Berlin, Germany In a mere 240 pages, A Little This Way to the Universe celebrates It can be easy to Book About the the ongoing effort to understand the take for granted Big Bang takes nature of reality. Theoretical physicist the images we readers through Michael Dine noticed there was no have of the other the mysterious single book to recommend for the worlds in our origin and layperson solar system, ultimate fate to find but these of the cosmos. out more pictures haven’t With the help about the always been at of analogies and Big Bang, our fingertips. step-by-step dark matter, In Imaging Our Solar System: The explanations, the Higgs Evolution of Space Mission Cameras physicist Tony Rothman breaks Boson, and and Instruments, Bernard Henin down the complexities of more — so walks readers through the marvels cutting-edge research probing he wrote it and missteps of putting imaging the laws of the universe. himself. instruments into space, from the 1940s to today. $24.95 $28.00 617.495.2600 consumerservices@ $29.99 (ebook); $37.99 (softcover) www.hup.harvard.edu penguinrandomhouse.com 800.777.4643 www.penguinrandomhouse.com https://link.springer.com Build Your Own HOME-DOME AND PRO-DOME MARKETPLACE OBSERVATORIES Custom Astronomical Adapter www.preciseparts.com +1 305 253-5707 [email protected] INDEX of ADVERTISERS Fine Meteorite Jewelry Phone: 407-601-1975 • www.homedome.com Armstrong Metalcrafts. . . . . . . . . . . . . . . . . . . . . . . 61 &In Gold Astronomy Exclusive 6” Saturn Globe . . . . . . . . 59 Box of Tricks Ltd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67 Platinum Cloud Break Optics . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Heritage Auctioneers & Galleries, Inc. . . . . . . . . . 2 www.NinePlanetsRing.com Insight Cruises. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 iOptron . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Miniature Inner Planet Orrery Metamorphosis Jewelry Design . . . . . . . . . . . . . . 61 Michael Gallagher . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 This orrery shows the correct motions of Mercury, NEAF DEALER PAGE. . . . . . . . . . . . . . . . . . . . . . . . . . 68 Venus, Earth, Moon, and Mars to 1% accuracy. Driven by Oberwerk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 a knob below the base, it’s a delightful demonstration Precise Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 Rainbow Symphony . . . . . . . . . . . . . . . . . . . . . . . . . 61 of the motions of our planetary neighbors. Scope Buggy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Space & Beyond Box. . . . . . . . . . . . . . . . . . . . . . . . . 13 Made from aircraft Technical Innovations . . . . . . . . . . . . . . . . . . . . . . . 61 grade aluminum Unistellar. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 and brass, the orrery measures The Advertiser Index is provided as a service to Astronomy 4 inches across. magazine readers. The magazine is not responsible for omissions or for typographical errors in names or Email [email protected] page numbers. www.armstrongmetalcrafts.com
A S K A S T R O Astronomy’s experts from around the globe answer your cosmic questions. hole mergers is significantly lower (longer) than those produced by stellar-mass black hole mergers. This makes them undetectable by LIGO, and so no direct detection of two supermassive black holes merging has been made yet. To make a direct observation, we will need instru- ments sensitive to the frequency of the gravitational waves produced in supermassive black hole mergers. Such instruments could include ground-based pulsar timing arrays — which use the stable and precise periods of neutron stars to search for gravitational waves — and space-based gravitational-wave observatories such as the Laser Interferometer Space Antenna (LISA), scheduled for launch in the next decade. When we are able to detect the gravitational waves from a supermassive black hole merger, it will be unlike any other black hole merger we’ve seen before. Most, if not all, stellar-mass black hole mergers detected by LIGO seem to have no accompanying electromagnetic coun- terparts (that is, events that give off light). But unlike their smaller counterparts, coalescing supermassive black holes are expected to occur in gas-rich environ- Two supermassive ments. This means that bright electromagnetic signals black holes spiral toward one another in would likely accompany the gravitational waves, making this simulation. NASA’S When black for a truly spectacular show. Xin Liu GODDARD SPACE FLIGHT CENTER holes collide Associate Professor, University of Illinois at Urbana-Champaign Q I WHAT WOULD HAPPEN IF TWO SUPERMASSIVE BLACK HOLES Q I HOW IS IT POSSIBLE, WITH ALL MERGED? THE MATTER IN THE UNIVERSE, THAT THE BIG BANG STARTED FROM Aaron James Oommen Doha, Qatar THE SIZE OF A PINHEAD? Pete Neiland Calgary, Alberta A I Supermassive black holes that are millions to billions of times more massive than the Sun are A I Our universe is and has been expanding commonly found at the hearts of galaxies. When galaxies throughout its history, and this means that it merge, their central black holes should also combine. was hotter and denser in the past than it is today. Any And when they do, these collisions are so powerful that they create distortions in space-time, known as given piece of space was smaller in the past than it is now. gravitational waves. These ripples were first theorized by Albert Einstein in his theory of general relativity in The fact that nothing can travel faster than the speed of 1916. Astronomers believe that the power output from the merger of two supermassive black holes would be light limits how much of our universe we can observe; briefly larger than the combined luminosity of all the stars in all the galaxies in the entire observable universe. the currently observable part of our universe is about The direct detection of the mergers of two stellar-mass 46.5 billion light-years in radius. black holes — about 3 to 10 solar masses — by the Laser Interferometer Gravitational-wave Observatory (LIGO) When the first stars were forming in our universe — a has ushered in the exciting new era of gravitational-wave astronomy. However, the frequency (or wavelength) of couple of hundred million years after the Big Bang — the the gravitational waves produced by supermassive black radius of what is now our observable universe was about 20 times smaller than it is today. When the first atoms were forming — a few hundred thousand years after the Big Bang — it was about 1,000 times smaller. The particle accelerator known as the Large Hadron Collider near Geneva, Switzerland, enables physicists to study the conditions that we think were in place when our universe was only a trillionth of a second old. At that time, the region of space that is now our observable universe was only a couple of hundred million kilometers in extent. 62 ASTRONOMY • JUNE 202 2
GROWING FROM THE BIG BANG Cosmic microwave background Diameter of the observable universe Big Bang Inflation Protons Nuclear Nuclear Neutral Modern form fusion fusion hydrogen universe begins ends forms 0 10-32 second 1 microsecond 0.01 second 20 minutes 380,000 years 13.8 billion years Age of the universe If we extrapolate even further back in time, we can all the atoms will break down into hydrogen. Then these imagine a hypothetical state that may have been present about 10–43 seconds after the Big Bang. The laws of phys- hydrogen atoms will slowly disappear through a hypo- ics as we currently understand them — including general relativity and quantum mechanics — don’t allow us to thetical process known as proton decay. extrapolate any further back than this so-called Planck time. (Read more on this cosmic era in Astronomy’s April To understand how long that would take, imagine if 2022 issue.) At the Planck time, the region that is now our observable universe would have been only a fraction you were to count every person on Earth (about 8 billion) of a millimeter in diameter, or smaller than the size of a pinhead. at a rate of one per year. By the time you finished, the You might think that at such incredible densities, the white dwarf would no longer shine. Then, if you were to matter and energy in our early universe would have col- lapsed, resulting in the formation of black holes. Black count every atom in every person on Earth — there are holes form, however, only when the matter and energy is distributed unevenly. In the early universe, the energy about 1028 atoms in a human body — at a rate of one atom was distributed in an almost perfectly uniform way throughout space. The homogeneity of the early universe per year, the star will have virtually disintegrated by the would have prevented any — or at the very least, many — black holes from forming. time you were done. Dan Hooper A neutron star is the remnant of a massive star that Senior Scientist, Fermi National Accelerator Laboratory, has run out of fuel, exploded, and collapsed into a super- Batavia, Illinois dense star. Like a white dwarf, a neutron star will cool over about 1010 years to a point where it no longer emits visible light. However, unlike white dwarfs, neu- tron stars have a thin crust sur- rounding densely Q I WHAT WILL WHITE DWARFS, packed neutrons. NEUTRON STARS, AND BROWN Over the next 1038 years, scientists DWARFS LOOK LIKE AT THE VERY END believe the crust OF THEIR LIVES, WHEN THEY NO LONGER will disintegrate EMIT RADIATION? thanks to proton SEND US YOUR QUESTIONS Bill Zuna decay. Eventually the gravitational force drops and the Tallahassee, Florida Send your star expands into something reminiscent of a white astronomy questions via email to askastro@ A I Let’s look at a white dwarf first. These stellar dwarf (which now only has another 1038 years to live). astronomy.com, or remnants are the remains of Sun-like stars and write to Ask Astro, Finally, a brown dwarf is barely visible to begin with. P.O. Box 1612, Waukesha, WI 53187. It doesn’t fuse hydrogen in its core, meaning it’s not a Be sure to tell us your full name and are made mostly of carbon and oxygen. A white dwarf’s true star. It might fuse deuterium, or heavy hydrogen, where you live. Unfortunately, we outer shell is so hot that it will radiate visible light for but that fusion will stop after a mere 108 years. Then it cannot answer all questions submitted. about 1010 — that’s 1 followed by 10 zeros — years. By too will slowly succumb to proton decay over 1038 years. then, the atoms will have cooled down enough that they It’s a very bleak future, but there is plenty of time until crystallize into a giant diamond. However, this diamond then! S.H.C. Cabot does not last forever. As time marches on for another Graduate Student, Department of Astronomy, Yale University, 1038years, the protons and neutrons inside all the atoms New Haven, Connecticut will disintegrate and produce scant traces of light. First, WWW.ASTRONOMY.COM 63
READER GALLERY Cosmic portraits 1. STELLAR SPAGHETTIOS 1 The Spaghetti Nebula (Simeis 147) 2 is a supernova remnant that spans 3 degrees of sky across Taurus and Auriga. Its low surface brightness makes it tricky to observe visually. This image comprises 55 hours of exposure with a 4.2-inch scope, mostly in HOO filters. • Yann Sainty 2. HUNTING COLORS Orion and Taurus glitter with cool blues and brilliant reds in this photocollage of stars that are magnitude 5 and brighter. They were captured with a smartphone through a telescope placed out of focus to emphasize the stars’ colors. • Paolo Palma 64 ASTRONOMY • JUNE 2022
3 3. ALL NIGHT LONG 45 A star party rages under 6 Californian desert skies in this image that spans seven hours. The photographer used a Canon EOS 6D Mark II to capture one-minute exposures at f/4 and ISO 4000. • Chris Cook 4. FULL SPEED AHEAD Heckathorn-Fesen-Gull 1 (upper right) is a planetary nebula in Cassiopeia about 2,300 light-years distant. It surrounds a white dwarf in a binary system moving through space at tens of kilometers per second — fast enough to form a bow shock in front of it and leave a tail of hot hydrogen gas in its wake. Abell 6, another planetary nebula, is at lower left. • Jon Talbot 5. IN PLAIN SIGHT IC 342 in Camelopardalis is just outside the Local Group of galaxies, only about 11 million light-years away. But the dust of the Milky Way dims it by a couple of magnitudes, giving it the nickname of the Hidden Galaxy. The image was taken with nearly 10 hours of exposure on a 12-inch scope. • Terry Riopka 6. THE PELICAN’S THROAT Impressive jets and pillars abound in this section of the Pelican Nebula (IC 5067/70) in Cygnus, where young stars are eroding away the dense gas and dust that birthed them. The image represents 19.5 hours of exposure with an 8-inch scope in the Hubble palette. • Hassan Abdollahabadi SEND YOUR IMAGES TO: Astronomy Reader Gallery, P.O. Box 1612, Waukesha, WI 53187. Please include the date and location of the image and complete photo data: telescope, camera, filters, and exposures. Submit images by email to readergallery@ astronomy.com. WWW.ASTRONOMY.COM 65
BREAKTHROUGH DANCING WITH THE DOLPHINFISH When observers size up the southern constellation Dorado the Dolphinfish, they usually focus on the Milky Way’s grand satellite galaxy, the Large Magellanic Cloud. But there’s another island universe within Dorado’s confines worth viewing: the Spanish Dancer Galaxy (NGC 1566). Despite lying some 50 million light-years away, this stunning face-on spiral glows at 10th magnitude. Part of its luminosity comes from an active nucleus powered by a supermassive black hole weighing nearly 10 million Suns. But the galaxy’s beauty stems from two graceful arms peppered with bright blue stars that wind out from a core filled with older, yellower suns. The reddish star just above the galaxy is an 8th-magnitude foreground object located 1,000 light-years from Earth. DARK ENERGY SURVEY/DOE/FNAL/DECAM/CTIO/NOIRLAB/NSF/AURA 66 ASTRONOMY • JUNE 202 2
Every element of your solar system model is the STANDING VIWYPXSJQIXMGYPSYWVIWIEVGLERHHIWMKRƼRI craftsmanship and precision engineering 37CM TALL $599 NOW $499 when you use the code ASY100 A Truly Unique Model (718) 690 3903 An Original Design Shipped from the United Kingdom with a tracked service, all duties paid, estimated delivery 10 to 14 days
B&H Photo – 800.947.9970 – bhphotovideo.com Astronomics – 800.422.7876 – astronomics.com Adorama – 800.223.2500 – adorama.com High Point Scientific – 800.266.9590 – highpointscientific.com OPT Telescopes – 800.483.6287 – optcorp.com Focus Camera – 800.221.0828 – focuscamera.com Optics Planet – 800.504.5897 – opticsplanet.com Woodland Hills – 888.427.8766 – telescopes.net Agena AstroProducts – 562.215.4473 – agenaastro.com
SOUTHERN SKY BY MARTIN GEORGE August 2022 Saturn reigns supreme As twilight fades to Mercury appears six times Planet crosses from Aries the brighter star eclipses the fainter darkness in early brighter than its companion. Ram into Taurus the Bull dur- one, we get a secondary eclipse. August, look for a conspicuous The pair stands 8° high in the ing August’s second week and point of light low in the east. west-northwest 45 minutes ends the month between the The sky’s best known Saturn dominates the constel- after the Sun sets. spectacular Pleiades and eclipsing binary is Algol (Beta lation Capricornus, shining Hyades star clusters. Our celes- [β] Persei), which dims from 10 times brighter than any of Mercury climbs steadily tial neighbor grows more its normal magnitude 2.1 to the Sea Goat’s stars. As impres- higher until it reaches greatest prominent this month as it magnitude 3.8 and then bright- sive as the planet appears to the elongation August 27. The brightens from magnitude 0.2 ens again during a 2.87-day naked eye, however, it truly innermost world then lies 27° to magnitude –0.1. orbital period. (The shallow shines when viewed through a east of the Sun and appears secondary eclipse can’t be telescope. And this month pro- 17° above the western horizon If you manage to stay awake detected visually.) Scientists vides skygazers with their best 45 minutes after sundown. a few more hours, be sure to detected Algol’s variability at views of the ringed world dur- Mercury then shines at magni- view Mars through your scope. least as early as the 17th cen- ing 2022. tude 0.3 and appears obvious By the end of August, the plan- tury, but it took the extensive Saturn reaches peak visibil- against the twilight back- et’s gibbous disk swells to 10\" in observations of English ity August 14. It then lies oppo- ground. Through a telescope, diameter and should show amateur astronomer John site the Sun in our sky, so it the planet shows a 7\"-diameter some subtle surface detail dur- Goodricke in 1782 and 1783 to rises at sunset, climbs highest disk that’s slightly more than ing moments of good seeing. establish the star’s periodicity. around local midnight, and half-lit. sets as the Sun comes up. Although Venus has been Unfortunately, Algol lies at Opposition also brings the Brilliant Jupiter arrives on a fixture in the morning sky a declination of 41° and never ringed planet closest to Earth, the scene later in the evening. It since January, its rule ends in climbs high from our part of so it shines brighter than at climbs well clear of the eastern August. Look for the planet the world. But the southern sky any other time this year, horizon by 11 p.m. local time in early this month, when it stands offers a nice alternative: Delta magnitude 0.2. early August and some two nearly 10° high in the northeast (δ) Librae. Delta stands high in Saturn’s telescopic appear- hours earlier by month’s end. a half-hour before sunrise. the northwest after darkness ance also peaks at opposition. The giant planet spends the Venus dazzles at magnitude –3.9 falls these August evenings. On the 14th, the planet’s disk month tucked in a corner of and looks conspicuous even in You can find it 4° west and a measures 18.8\" across while the Cetus the Whale just across bright twilight. Alas, the inner touch north of magnitude 2.6 rings span 42.6\" and tilt 14° to that constellation’s border with world disappears in the Sun’s Beta Lib. our line of sight. Any telescope Pisces the Fish. Jupiter bright- glare after midmonth. delivers stunning views of the ens from magnitude –2.7 to Delta shines at a modest rings and also reveals its largest magnitude –2.9 during August, The starry sky magnitude 4.9 at maximum satellite, 8th-magnitude Titan. far outshining the dim stars in brightness and magnitude 5.9 A 10-centimeter instrument its vicinity. Most variable stars change at minimum, so binoculars will brings in three or four addi- brightness in response to help you to track its changes. It tional moons. Wait at least a couple of intrinsic variations in the star takes 2.33 days to complete a One other naked-eye planet hours after the planet rises itself. But one type of variable cycle. Like Algol, Delta’s sec- graces August’s early evening before targeting it with your — an eclipsing binary — owes ondary eclipse is too shallow to sky, as Mercury puts on its best telescope. Jupiter’s disk mea- its brightness fluctuations to observe. Unlike Algol, however, performance of the year. Try to sures 47\" across in mid-August the orientation of the system’s Delta does not remain at maxi- catch it on the 4th, when the and shows lots of detail in its orbit. If we view the binary’s mum light for long. Its rela- planet passes within 1° of Leo’s cloud tops. Also keep an eye orbit edge-on (or nearly so), the tively smooth rise and fall brightest star, 1st-magnitude on the gas giant’s four bright two stars eclipse each other. — coupled with a period that’s Regulus. At magnitude –0.5, moons as they change position When the dimmer star passes eight hours off from a whole from night to night. in front of the brighter one, we number of days — means you see a so-called primary eclipse; can see it vary quite easily from The wee hours bring gor- half an orbit later, when the night to night. geous views of Mars. The Red
STAR DOME S CARINA MENSA LMC VO L A N S NGC 2516 NGC 2070 HOW TO USE THIS MAP VELA CHAMAELEON SMC HYDRUS This map portrays the sky as seen near 30° south latitude. Located SW M64 NW NGC 3372 GC 104 SCP inside the border are the cardinal directions and their intermediate X RU b O CTANS points. To find stars, hold the map overhead and orient it so one of C _ the labels matches the direction you’re facing. The stars above a NGC 51394755 NGC TARUISATNRGAULLEU M the map’s horizon now match ` what’s in the sky. ` PAVO The all-sky map shows HYDRA C E NNTGACU5R12U8S _ how the sky looks at: CIRCINUS NGC 6397 9 P.M. August 1 8 P.M. August 15 C R AT E R CORVUS NORMA ARA TELESCOPIUM 7 P.M. August 31 M83 LUPUS NGC 6231 CAOURSOTNRAA L I S Planets are shown at midmonth MAP SYMBOLS M104 SCORPIUS M7 M6 Open cluster W Path of the Sun (ecliptic) Spica LIBRA Antares Globular cluster M4 Diffuse nebula M8 Planetary nebula Galaxy M20 M17 M22 M16 M VIRGO TU U C S M11 M5 OPHIUCHUS STAR C ASEPRUPTE N S SE AR UP EDNAS MAGNITUDES C Arcturus Sirius 0.0 3.0 VULPE 1.0 4.0 2.0 5.0 STAR COLORS BOÖTES BCOORREOANL IAS M13 LY R A HERCULES Vega A star’s color depends on its surface temperature. N The hottest stars shine blue •• Slightly cooler stars appear white • Intermediate stars (like the Sun) glow yellow • Lower-temperature stars appear orange • The coolest stars glow red • Fainter stars can’t excite our eyes’ color receptors, so they appear white unless you use optical aid to gather more light BEGINNERS: WATCH A VIDEO ABOUT HOW TO READ A STAR CHART AT www.Astronomy.com/starchart.
AUGUST 2022 SAT. SUN. MON. TUES. WED. THURS. FRI. INDU GRUS FomalhautP IASUCSITSR I N U S 1 23456 ILLUSTRATIONS BY ASTRONOMY: ROEN KELLY TUCANA PHOENIX SE 7 8 9 10 11 12 13 Achernar 14 15 16 17 18 19 20 S A G I T TA R I U S E CAPRICORNUS 21 22 23 24 25 26 27 A Q UA R I U S MICROSCOPIUM 28 29 30 31 Saturn Note: Moon phases in the calendar vary in size due to the distance AQUILA Altair EQUULEUS M15 from Earth and are shown at 0h Universal Time. Enif DELPHINUS CALENDAR OF EVENTS ECULA S A G I T TA 1 Mars passes 1.4° south of Uranus, 9h UT NE 4 Mercury passes 0.7° north of Regulus, 5h UT 5 First Quarter Moon occurs at 11h07m UT CYGNUS 7 Venus passes 7° south of Pollux, 10h UT 10 The Moon is at perigee (359,828 kilometers from Earth), 17h09m UT 12 Full Moon occurs at 1h36m UT The Moon passes 4° south of Saturn, 4h UT 14 The Moon passes 3° south of Neptune, 10h UT Saturn is at opposition, 17h UT 15 The Moon passes 1.9° south of Jupiter, 10h UT 18 The Moon passes 0.6° north of Uranus, 15h UT 19 Last Quarter Moon occurs at 4h36m UT The Moon passes 3° north of Mars, 12h UT 22 Asteroid Vesta is at opposition, 19h UT The Moon is at apogee (405,418 kilometers from Earth), 21h52m UT 24 Uranus is stationary, 15h UT 25 The Moon passes 0.7° south of dwarf planet Ceres, 19h UT The Moon passes 4° north of Venus, 21h UT 27 New Moon occurs at 8h17m UT Mercury is at greatest eastern elongation (27°), 16h UT 29 The Moon passes 7° north of Mercury, 11h UT
1000 OVER PRODUCTS! EXPLORE THE INCLUDING EXCLUSIVES FROM ASTRONOMY UNIVERSE Visit MyScienceShop.com today for high-quality products curated by the Astronomy magazine team, including: • Custom-produced globes, as well as others from top manufacturers. • Books and DVDs covering solar eclipses, observing guides, the cosmos and more. • Magazines bringing you the latest astronomical discoveries and events. • Astronomy posters including many sold exclusively on MyScienceShop.com. • Toys and games–have fun learning about astronomy! • And much more! MShoypSnocwieat:nceShop.com Sales tax where applicable. P39082
Search
