Daily Archives: January 10, 2024

Active supermassive black holes often produce powerful jets of ionized gas that stream away from their host galaxies. These jets can be seen by radio telescopes as radio lobes. Active galaxies can have one or two radio lobes, and when they have two they are known as Double-lobed Radio sources associated with Active Galactic Nuclei, or DRAGNs. The jets of most DRAGNs are symmetrical, but a few are not. These asymmetrical DRAGNs could tell us a great deal about galaxies and their surrounding environment, but identifying them can be a challenge.

University of the West Indies student Kavita Gosine Bissessar wanted to find these asymmetrical DRAGNs, so she started with a catalog of 17,724 DRAGNs captured by the Very Large Array Sky Survey (VLASS). She combined this with infrared data from the Wide-field Infrared Survey Explorer (WISE) to identify their host galaxies. From this Kavita found that 1,587 of them had confirmed galactic cores.

But to find out which of these were asymmetrical, Kavita had to comb through them by hand. She started by measuring the arm-core distance ratio since DRAGNs with larger ratios are more likely to be symmetrical. She found that 33 of them had ratios greater than 3.6. Interestingly, she found that those with the largest ratios appeared asymmetrical, but were actually false positives. Some were actually two separate galaxies, while others had bright radio cores misidentified as a lobe. Kavita found that DRAGNs with arm-core distance ratios between 3 and 8 had the greatest chance of being true asymmetrical DRAGNs.

This result can help astronomers find galaxies with asymmetric radio lobes more easily. In the future Kavita would like to study the environments of these galaxies to see how that might affect galactic lobe symmetry.

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Here There Be DRAGNs National Radio Astronomy Observatory - National Radio Astronomy Observatory

French telescope company Unistellar has launched two new tech-infused models at CES 2024 promising to eliminate the tedious parts of backyard astronomy. The new Odyssey and Odyssey Pro smart telescopes use new technology to focus on both nearby objects like Jupiter and distant stars or nebulae. They also feature new Nikon optics and an updated smartphone app that helps you align and focus the telescope, while automatically finding targets to image.

Unistellar's current smart telescopes, the eVscope 2 and eQuinox 2, are primarily designed to image distant galaxies, stars, clusters and the like they can also image planets, but focus can be tricky. However, the Odyssey and Odyssey Pro use what the company calls Multi-Depth technology to focus equally well on both near and far objects, letting you switch instantly from viewing the Moon to a distant nebula.

It works by using the full sensor resolution to image close-in objects, which are bright but relatively small. For dim, larger objects it combines four pixels into one, much like many smartphone cameras, to boost the light gathering capability, at the cost of some detail. As the company told us at CES, it also "stacks multiple images of the same spot to render a clean output."

They even work in light-polluted areas, thanks to a high-sensitivity sensor and smart image processing. "With the Odyssey, Unistellar is offering a new generation of smart telescopes that are both ultra-powerful and capable of instantly transforming your stargazing evenings into adventures across the cosmos with family or friends, even in the middle of the city," said Laurent Marfisi, Unistellar co-founder and CEO.

The other big update is the Android/iOS app. As before, it automatically points the telescope toward the desired target at the right time, by recognizing groups of stars and calculating exactly where a target should be. However, it can now suggest items to look at on a particular evening, and provide extra context about the body in question.

Both telescopes have new optical tubes using Nikon optics and the company says they're the first that don't need manual adjustments something that can be difficult for amateur astronomers. That marries with a new autofocus system much like what you'd see on a digital camera to deliver consistently sharp images.

The new telescopes are cheaper than past models, though they do have smaller mirrors than the eVscope 2, at 320mm compared to 450mm focal length. The main difference between the two models is that the Odyssey Pro has slightly more resolution (4.1 megapixels compared to 3.4 megapixels), along with a Nikon-made eyepiece. The Odyssey is now shipping for $2,499, while the Odyssey Pro costs $3,999. The company also has a special edition Odyssey Pro Red Edition (above), that costs $4,499.

Engadget's Richard Lai contributed to this report.

We're reporting live from CES 2024 in Las Vegas from January 6-12. Keep up with all the latest news from the show here.

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Unistellar's latest smart telescopes take the hassle out of backyard astronomy - Engadget

The red spots at the top of the corona of the Sun during the total solar eclipse are called Bailey's beads. This image was taken during the Great American Eclipse of 2017. NASA Photo / Carla Thomas

The total solar eclipse set to occur April 8, 2024, will dazzle everyone who views it. However, potential observers might have some questions.

Where exactly in Mexico and the U.S. will totality be visible? Thats easy to answer with a detailed map, such as the one below. But which locations are the best spots to view the event? That answer is less straightforward.

Youll surely want to set up shop near the center line of the eclipse, where totality will last the longest. But what else makes for a good viewing site for a total solar eclipse? Below are 20 great locations you should consider for the 2024 Great North American Eclipse, starting in Mexico and working to the Northeast U.S.

Ill also offer one other suggestion when choosing a site: Carefully consider the population. All things being equal, a town of 10,000 is much more likely to have event-related problems than a city of 75,000. Traffic will be one of the primary issues; small communities with one main road may suffer hours of gridlock. If you opt to travel to such a location, get there early perhaps even a day or two ahead of the eclipse. (Remember: April 8, 2024, is a Monday, and most people will be free the entire weekend beforehand.)

Drive safe anddont forget your eclipse glasses. I wish you all clear skies!

The Moons umbra touches the coast of the United Mexican States at 12:07 p.m. Mexican Pacific Daylight Time less than 12 miles (19 km) southeast of Mazatln, which was one of the main destinations for travelers viewing the July 11, 1991 total solar eclipse. This city knows how to host a large influx of travelers, so its a good bet that it will be a prime destination.

Eclipse starts:9:51:28 a.m. MPDT Eclipse ends:12:32:11 p.m. MPDT Maximum eclipse:11:09:39 p.m. MPDT Suns altitude at maximum eclipse:69.1 Duration of totality:4 minutes 18 seconds Width of Moons shadow:123.7 miles (199.1 km)

At 1:15 p.m. Mexican Central Daylight Time, the umbra arrives at Nazas. This town of some 4,000 residents will surely see that number swell because it is the nearest location to the point of longest totality. The town itself will enjoy that duration, but the actual spot is about 3 miles (5 km) to the north, just east of Durango Paso Nacional, the road that connects Nazas to San Luis del Cordero. If youre headed here for the longest possible totality, get there at least a day early.

Eclipse starts:11:58:24 a.m. MCDT Eclipse end:2:39:42 p.m. MCDT Maximum eclipse:1:17:17 p.m. MCDT Suns altitude at maximum eclipse:69.8 Duration of totality:4 minutes 28 seconds Width of Moons shadow:122.6 miles (197.4 km)

Related: The best equipment to see an eclipse | How to make a pinhole camera out of a cardboard box

A large city that lies across the Rio Grande River from Eagle Pass, Texas, is Piedras Negras. Anyone from the U.S. who wants to experience the maximum duration of totality (4 minutes 28 seconds), will either cross the Eagle PassPiedras Negras International Bridge or the Camino Real International Bridge. Using Piedras Negras as a base is a good idea because its metro population is a quarter million, so it contains lots of amenities for travelers.

Eclipse starts:12:10:08 p.m. CDT Eclipse end:2:51:17 p.m. CDT Maximum eclipse:1:29:37 p.m. CDT Suns altitude at maximum eclipse:68.6 Duration of totality:4 minutes 25 seconds Width of Moons shadow:120.9 miles (194.5 km)

For eclipse chasers who want the greatest possible amount of totality without leaving the U.S., consider Radar Base, which lies right on the U.S.Mexico border. Its name, by the way, isnt that of a military base but instead a small town of several hundred residents. That number will balloon on eclipse day, so be sure to get there early.

Eclipse starts:12:10:26 p.m. CDT Eclipse end:2:51:30 p.m. CDT Maximum eclipse:1:29:53 p.m. CDT Suns altitude at maximum eclipse:68.5 Duration of totality:4 minutes 27 seconds Width of Moons shadow:120.9 miles (195.5 km)

While San Antonio certainly will be the base of operations for many eclipse chasers, most will not stay there, opting instead to head to the center line for an additional minute of umbral darkness. Several small towns lie centered in the path, the largest of which is Kerrville, with roughly 24,000 residents. Be sure to check in advance for any eclipse-related activities.

Eclipse starts:12:14:43 p.m. CDT Eclipse end:2:55:29 p.m. CDT Maximum eclipse:1:34:17 p.m. CDT Suns altitude at maximum eclipse:67.5 Duration of totality:4 minutes 25 seconds Width of Moons shadow:120.2 miles (193.4 km)

NASA/Bill Ingalls

Many travelers will choose to base in Austin, the state capital of Texas. Its a good choice because that city features lots of amenities, especially in the food and music realms. Unfortunately, it lies near the southern limit of the path of totality. So, a good choice on eclipse day would be to drive the 68 miles (109 km) north to Lampasas, which lies quite near the center line.

Eclipse starts:12:18:03 p.m. CDT Eclipse ends:2:58:23 p.m. CDT Maximum eclipse:1:37:35 p.m. CDT Suns altitude at maximum eclipse:66.5 Duration of totality:4 minutes 24 seconds Width of Moons shadow:119.7 miles (192.6 km)

Although not a huge city, Hillsboro is an easy destination, lying, as it does, on Interstate 35 where I-35E and I-35W split south of Dallas. It also lies right along the center line of totality, which will help maximize your time under the Moons umbra.

Eclipse starts:12:21:23 p.m. CDTEclipse ends:3:01:16 p.m. CDTMaximum eclipse:2:40:53 p.m. CDTSuns altitude at maximum eclipse:65.5 Duration of totality:4 minutes 23 seconds Width of Moons shadow:119.2 miles (191.8 km)

Another great location in the Lone Star State is Sulphur Springs. It lies along Interstate 30, so getting there wont be a problem. Although the city isnt huge (less than 20,000 residents), there are many open areas. One is Coleman Lake and Park, which offers 186 acres with trails and waterfalls. Cooper Lake State Park lies 15 miles (24 km) north. It has more than 2,500 acres of land and nearly 20,000 acres of lake. Observing from a boat would certainly be relaxing. And youll only lose 2 seconds of totality compared to Sulphur Springs.

Eclipse starts:12:25:38 p.m. CDT Eclipse ends:3:04:52 p.m. CDT Maximum eclipse:1:45:04 p.m. CDT Suns altitude at maximum eclipse:64 Duration of totality:4 minutes 21 seconds Width of Moons shadow:118.4 miles (190.6 km)

With a population near 30,000, Russellville has enough resources to host a moderate influx of visitors for the eclipse. Those eclipse chasers who prefer to observe the event outside the city could head for nearby Mount Nebo, a flat-topped mountain that rises 1,350 feet (410 meters) above the surrounding valley.

Eclipse starts:12:33:08 p.m. CDT Eclipse ends:3:10:46 p.m. CDT Maximum eclipse:1:52:10 p.m. CDT Suns altitude at maximum eclipse:49.0 Duration of totality:4 minutes 11 seconds Width of Moons shadow:117.2 miles (188.6 km)

The largest city in southeastern Missouri that will experience totality is Cape Girardeau, with its 80,000 residents. It lies on the bank of the Mississippi River and is easily accessible from Interstate 55. For an additional 4 seconds of totality, eclipseophiles can head 10 miles (16 km) west on State Route 72 to Jackson. Eclipse starts:12:41:51 p.m. CDT Eclipse ends:3:17:26 p.m. CDT Maximum eclipse:2:00:21 p.m. CDT Suns altitude at maximum eclipse:57.3 Duration of totality:4 minutes 6 seconds Width of Moons shadow:115.5 miles (185.9 km)

This small city of some 16,000 residents lies along U.S. Highway 50 (east-west) and U.S. Highway 150, which becomes U.S. Hwy. 41 (north-south). Its a quick hop from Interstate 69. More importantly, it sits squarely on the eclipses center line, so it will probably be a popular destination for inhabitants of the region. Eclipse starts:1:46:59 p.m. EDT Eclipse ends:4:20:57 p.m. EDT Maximum eclipse:3:04:55 p.m. EDT Suns altitude at maximum eclipse:54 Duration of totality:4 minutes, 5 seconds Width of Moons shadow:114.5 miles (184.3 km)

The umbra will cover a wide swath of Indiana, but most of the attention will focus on the states capital city. Downtown Indianapolis is a metropolis served by four interstate highways and will surely be one of the most sought-after destinations. It offers plentiful lodging, excellent cuisine, and many attractions for travelers.

Eclipse starts:1:50:31 p.m. EDT Eclipse ends:4:23:10 p.m. EDT Maximum eclipse:3:07:56 p.m. EDT Suns altitude at maximum eclipse:53 Duration of totality:3 minutes 49 seconds Width of Moons shadow:114 miles (183.4 km)

This small city of 36,000 is well positioned for viewing the eclipse and is just large enough to handle a moderate influx of visitors. For those who want the maximum possible length of totality, youll get 6 additional seconds if you drive south on Interstate 75 to Wapakoneta, and an extra second if you continue south to the center line.

Eclipse starts:1:54:51 p.m. EDT Eclipse ends:4:26:01 p.m. EDT Maximum eclipse:3:11:43 p.m. EDT Suns altitude at maximum eclipse:50.8 Duration of totality:3 minutes 51 seconds Width of Moons shadow:113 miles (181.9 km)

With a metro population of more than 2 million, this city will host a multitude of eclipse chasers. Get there a couple of days early, and fill the waiting time with visits to some of Clevelands highlights, including the Cleveland Museum of Arts and the Rock and Roll Hall of Fame.

Eclipse starts:1:59:20 p.m. EDT Eclipse ends:4:28:57 p.m. EDT Maximum eclipse:3:15:37 p.m. EDT Suns altitude at maximum eclipse:48.6 Duration of totality:3 minutes 49 seconds Width of Moons shadow:111.9 miles (180.1 km)

The only large city in the Commonwealth of Pennsylvania to be graced by the Moons umbra is Erie, which, with its 100,000 residents, sits on the shore of the Great Lake that bears its name. Its certain that many eclipse chasers from Pittsburgh, 130 miles to the south via Interstate 79, will visit for the event.

Eclipse starts:2:02:23 p.m. EDT Eclipse ends:4:30:48 p.m. EDT Maximum eclipse:3:18:12 p.m. EDT Suns altitude at maximum eclipse:47 Duration of totality:3 minutes 42 seconds Width of Moons shadow:111.2 miles (179 km)

If the Northeastern United States has good weather on eclipse day, the most picturesque images of the event might come from Niagara Falls. One of the best perspectives will come from the outlook called Terrapin Point, where the Sun will hang halfway up in the southwest directly over the Falls! Science buffs who observe or photograph the eclipse from this area surely will want to visit the Nikola Tesla Statue within Queen Victoria Park on the Canadian side of Niagara Falls. It lies only 0.3 mile (0.5 km) north of Terrapin Point.

Eclipse starts:2:04:50 p.m. EDT Eclipse ends:4:31:57 p.m. EDT Maximum eclipse:3:20:02 p.m. EDT Suns altitude at maximum eclipse:45.6 Duration of totality:3 minutes 31 seconds Width of Moons shadow:110.8 miles (178.4 km)

The largest city in New York that will experience the Moons umbra is Buffalo, with its metropolitan population of 1.1 million. The center line passes right through downtown, so expect all activity to come to a screeching halt in mid-afternoon. Travelers desiring information about the eclipse might want to check with the staff of Zygmunt Planetarium, which is part of the Buffalo Museum of Science.

Eclipse starts:2:04:54 p.m. EDT Eclipse ends:4:32:07 p.m. EDT Maximum eclipse:3:20:11 p.m. EDT Suns altitude at maximum eclipse:45.6 Duration of totality:3 minutes 45 seconds Width of Moons shadow:110.7 miles (178.2 km)

This small city of roughly 20,000 residents makes this list primarily because its a one-hour drive from Montral, Canadas second most populous city. Montral itself will enjoy nearly 2 minutes of totality, but all serious eclipse chasers will head south to the center line for that additional 90 seconds. Good choice.

Eclipse starts:2:14:02 p.m. EDT Eclipse ends:4:37:04 p.m. EDT Maximum eclipse:3:27:29 p.m. EDT Suns altitude at maximum eclipse:40.4 Duration of totality:3 minutes 33 seconds Width of Moons shadow:108.4 miles (174.5 km)

Those Canadians who may not wish to cross the border can opt for Sherbrooke, which is only a 100-mile (161 km) drive from Montral. With a metro population of nearly a quarter million, Sherbrooke offers plenty of lodging and other amenities. And a quick 10-mile (16 km) drive south will bring you to the center line and 5 additional seconds of totality.

Eclipse starts:2:16:35 p.m. EDT Eclipse ends:4:38:13 p.m. EDT Maximum eclipse:3:29:23 p.m. EDT Suns altitude at maximum eclipse:38.8 Duration of totality:3 minutes 25 seconds Width of Moons shadow:107.8 miles (173.5 km)

To be honest, Mars Hill is a small town of some 1,500 residents. But just think of it: an amateur astronomer watching the Moon cover the Sun from a place named Mars Hill? Terrific. This location also is one of the last spots in the U.S. to see totality. But if youre one of those serious types, just drive 20 miles (32 km) south for an additional 10 seconds of totality.

Eclipse starts:2:22:20 p.m. EDT Eclipse ends:4:40:52 p.m. EDT Maximum eclipse:3:33:41 p.m. EDT Suns altitude at maximum eclipse:35.2 Duration of totality:3 minutes 12 seconds Width of Moons shadow:106.2 miles (171 km)

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20 of the best places to view the 2024 total solar eclipse - Astronomy Magazine

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Simulations show it's possible for lunar material to achieve a quasi-satellite orbit like Kamo`oalewa.

By using the NASA's JPL Small-body Database Lookup, the orbit of 469219 Kamo'oalewa can be displayed alongside Earth's orbit. The orbits appear to be nearly identical but just shifted. In the bottom-left corner it provides the distance from Kamo'oalewa to Earth and to the Sun. Credit: NASA

Normally, near-Earth objects (NEOs) are either asteroids or comets that are gravitationally influenced enough by nearby planets to enter Earths neighborhood. However, in April 2016, a group of astronomers discovered a near-Earth asteroid named Kamooalewa (pronounced kamo-o-a-lewa) and provisionally designated (469219) 2016 HO3, that appeared to be an outlier compositionally.

Fast forward five years and a team of astronomers from the University of Arizona suggested that the object could have originated from the Moon, since it shared more similarities with our earth-bound satellite than any other known asteroid.

Two years and a second University of Arizona team later, this time led by a graduate student in the Department of Physics, Jose Daniel Castro-Cisneros, the 2016 study and a 2021 study pushed a step further to confirm their idea.

Several teams are dedicated to detecting NEOs because asteroids and comets close to Earth can reveal key details about the early days of the solar system. Many asteroids and comets are relatively pristine since their formation, offering a window to the distant past. So, when the results for Kamooalewa differed, the team knew something unusual was going on.

Kamooalewa stood out for several reasons. First, it is classified as a quasi-satellite, meaning that it seems to orbit Earth but is really orbiting the Sun in an earth-like orbit. Second, Kamooalewa displays loyalty to Earth through its longevity. Usually, objects with earth-like orbits are stable for only a few decades, but Kamooalewa is expected to have a dynamical lifetime of millions of years. Further, the objects spectrum offered clues to its unusual composition. Astonishingly, the spectrum matches lunar material and suggests the object is a small piece of the Moon.

We looked at Kamooalewas spectrum only because it was in an unusual orbit, says Regents Professor of Planetary Sciences and co-author Renu Malhotra of the University of Arizona. If it had been a typical near-Earth asteroid, no one would have thought to find its spectrum and we wouldnt have known Kamooalewa could be a lunar fragment.

The spectrum shows that Kamooalewa is silicate-rich, a typical find in lunar-like material. Its history is partially revealed through extensive space weathering and reddening, beyond what is seen in nearby asteroids. Given the findings, the team suggested that Kamooalewa could have been ejected from one of the many meteorite impacts that have struck the Moon.

An ejected piece of Moon entering a quasi-earth-satellite orbit was always considered an unlikely phenomenon. Normally, when objects impact the Moon, the ejecta can either fall back on the Moons surface or even Earths surface. In rare cases the right amount of kinetic energy exists to launch material out of the Earth-Moon system but too much to enter earth-like orbits. Kamooalewa is testing this idea and now, the Castro-Cisneros team is testing Kamooalewa.

The 2023 group is using numerical simulations to show that it is, indeed, feasible for lunar material to achieve a quasi-satellite orbit. We are now establishing that the Moon is a more likely source for Kamooalewa, says Malhotra.

Castro-Cisneros plans on developing a simulation that creates a free pathway for Kamooalewa to reach Earths co-orbital space, and to calculate its age. Numerical computations like these will improve the understanding of NEOs. Whats more, these studies can help our space forces combat asteroids that may pose dangers to Earth.

If youd like to know more, feel free to read University of Arizonas news release, or some of our articles on either tracking NEOs or about the Apollo 17 lunar samples that revealed secrets of the Moons violent origin.

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Evidence builds that Kamo'oalewa is a chunk of the Moon accompanying Earth - Astronomy Magazine

The constellation Scorpius sits beneath the arch of the Milky Way in this image. The yellow-orange star near the branches is Antares, which receives several visitors this week. Credit: Luis Argerich (Flickr)

Friday, January 5 The mighty ringed planet Saturn remains a fixture in the southwestern sky after sunset, shining at magnitude 0.9. Youll find it still 30 high an hour after sunset, to the upper right of a relatively bright star that sits about half as high above the horizon thats Fomalhaut, the magnitude 1.2 alpha star of Piscis Austrinus the Southern Fish.

Through a telescope, Saturns disk stretches 16 across, with its rings just over twice that width. Those rings are tilted 9 to our line of sight, still showing off their northern side before next years ring plane crossing.

With no Moon in the sky, try to catch Saturn during the window starting after the sky is dark but before the planet sinks too low. You might spot several of its moons clustered nearby. The brightest at roughly magnitude 9 is Titan, which sits just southeast of the planet. It passes south of the gas giant overnight and will be southwest of the world tomorrow. Also visible may be 10th-magnitude Tethys, Rhea, and Dione. Tethys sits west of Saturn, about 17 from the western tip of the rings, Rhea is close to the disk and slightly northeast, while Dione is just south of the eastern tip of the rings. Even fainter moons are also present, but youll need a large telescope to see them. Iapetus, now a challenging 12th magnitude, reaches its eastern elongation tomorrow and sits a whopping 7.7 east of Saturn tonight.

Sunrise: 7:22 A.M. Sunset: 4:49 P.M. Moonrise: 1:21 A.M. Moonset: 12:15 P.M. Moon Phase: Waning crescent (35%) *Times for sunrise, sunset, moonrise, and moonset are given in local time from 40 N 90 W. The Moons illumination is given at 12 P.M. local time from the same location.

Saturday, January 6 Venus passes 6 north of the bright star Antares at 3 A.M. EST. You can catch the pair about an hour before sunrise in the southeast, when magnitude 4 Venus appears just to the upper left of the magnitude 1.1 star. Its a lovely pairing, particularly because of Antares deep red color. This aging star has cooled down as its fuel runs low, lending it a ruby hue.

Adding to the sight, the delicate crescent Moon (just less than 30 percent lit) lies in Libra, to Venus and Antares upper right. The scene is an appealing one for astrophotographers as morning twilight begins to color the sky and the trio rises higher. The Moon will track east and pass close to both Antares and Venus in just a few days, so stay tuned to the morning sky for more.

If you prefer observing in the evening, theres some action for you tonight as well: The Galilean moons Europa and Ganymede are transiting the face of Jupiter. The event is underway at sunset in the Midwest, when Jupiter is high in the southeast. By 5:50 P.M. EST, Ganymede is just finishing its transit, about to slip off the southwestern limb of the planet. Europa is not yet halfway across, making its way from east to west south of Jupiters equator. It will finally exit the disk just before 7:30 P.M. EST, following Ganymede and pulling away to the west.

Keep watching and youll catch Europas shadow appear on the cloud tops not long after, around 7:40 P.M. EST. Nearly two hours later, Ganymedes much larger shadow joins it at 9:20 P.M. EST. The shadow is so large that it takes some 10 minutes to fully appear against the disk. The dark blot will then take almost two hours to cross Jupiters southern polar region.

Sunrise: 7:22 A.M. Sunset: 4:50 P.M. Moonrise: 2:25 A.M. Moonset: 12:40 P.M. Moon Phase: Waning crescent (26%)

Sunday, January 7 Colorful stars can be a delight to observe, particularly when they come in contrasting sets. If youre willing to stay out over the course of a few hours this evening, you can check out two particularly popular pairs: the famous star Albireo in Cygnus and its wintertime counterpart 145 Canis Majoris.

Lets start with Albireo itself, cataloged as Beta () Cygni. Youll want to observe this one first, as the Swan is setting in the west as the sky grows dark after sunset. Albireo marks the head of the graceful bird as it flies through the sky; the bright star Deneb (Alpha [] Cyg) is the Swans tail. Ninety minutes after sunset, Albireo is roughly 20 high. It glows at magnitude 3.1, readily visible to the naked eye. Pull out a telescope and youll discover not one but two stars, separated by about 35. The brighter sun shines golden yellow, while the fainter star is a hotter blue-white. Their stunning color contrast is readily visible to most observers.

A few hours later, around 9:30 P.M. local time, Cygnus has set but the stars of Canis Major have climbed high enough in the southeast to track down the so-called Winter Albireo. 145 Cma is fainter than Albireo at magnitude 4.8; it lies 3.5 northeast of magnitude 1.8 Wezen (Delta [] Cma) and about 10 east-southeast of Sirius, the brightest star in the northern sky. This beautiful double star looks much like Albireo, with a cooler but brighter yellow-orange primary and a hotter secondary of blue-white. This pair is slightly closer, roughly 27 apart still easy to split with most instruments.

Sunrise: 7:22 A.M. Sunset: 4:50 P.M. Moonrise: 3:34 A.M. Moonset: 1:12 P.M. Moon Phase: Waning crescent (17%)

Monday, January 8 Now its the Moons turn to visit Antares in Scorpius, passing just 0.8 north of the star at 10 A.M. EST. The Moon then passes 6 south of Venus at 3 P.M. EST.

Again, early morning is time to observe this scene. Look southeast around 6:15 A.M. local time to find the trio 12 high and rising as the sky starts to lighten with the coming dawn. The Moon is now just a sliver of light, roughly 11 percent lit with only its western limb illuminated as it wanes toward New. It sits about 1 from Antares, directly between this star and nearby magnitude 2.9 Sigma () Scorpii. About 5.7 north-northeast of the Moon is Venus, just waiting for Luna to slip due south in a few hours.

Take out a telescope for a more detailed view. On the Moon, you may be able to spot the small, dark round blot of Grimaldi Crater near the terminator that separates lunar night from day. Venus is also an excellent target, presenting an 80-percent-lit face that is a hefty 14 across. Even as the stars begin to fade, bright Venus will continue to stand out in fact, observing the planet in the brightening sky often offers a better view because of the lower contrast. Just take care to put away any optics well in advance of sunrise from your location, which may differ slightly from the time given at our standard location below.

Sunrise: 7:22 A.M. Sunset: 4:51 P.M. Moonrise: 4:44 A.M. Moonset: 1:53 P.M. Moon Phase: Waning crescent (10%)

Tuesday, January 9 Continuing its trek across the ecliptic, the Moon passes 7 south of Mercury at 2 P.M. EST. Mercury, too, is a morning planet, so youll need to be up early to catch this pairing as well.

Look southeast an hour before sunrise and the first thing youll likely spot is again bright Venus. Its the brightest thing in the sky! Drop down closer to the horizon and a little to the left to find the 5-percent-illuminated Moon and, to its upper left, magnitude 0.1 Mercury. The solar systems smallest planet spans just 7 on the sky, but through a telescope will readily show off its roughly half-lit (56 percent) face.

As you enjoy the scene, note the distance between Mercury and Venus. They are now 12.5 apart, but will move slightly closer day by day until the 17th, when they stand 11 apart. It can be hard to notice subtle motion one day at a time, so consider taking a shot of the morning sky as dawn approaches and then doing so again every day or two for the next week. Comparing your photos over time may better show the planets motion as they close in.

Sunrise: 7:22 A.M. Sunset: 4:52 P.M. Moonrise: 5:55 A.M. Moonset: 2:45 P.M. Moon Phase: Waning crescent (4%)

Wednesday, January 10 The Moon passes 4 south of Mars at 4 A.M. EST; the Red Planet, however, is still too close to the Sun and not yet visible. It should finally pop out from our stars bright glow next week.

In the evening sky tonight, asteroid 4 Vesta is passing near the famous supernova remnant M1 in Taurus this week. Often called the Crab Nebula, this glowing tangle of gas is all thats left of a massive star. Its explosive end was seen by astronomers on Earth in the year 1054.

Lets start by finding 3rd-magnitude Alheka (Zeta [] Tauri), already 40 high in the east two hours after sunset. This star marks the tip of Taurus southern horn, while Elnath marks the northern horns tip. M1 lies just 1 northwest of Alheka and tonight Vesta sits roughly between them, about 30 northwest of Alheka.

Vesta is 7th magnitude, about a full magnitude brighter than the magnitude 8.4 Crab. The two look quite different, with the asteroid resembling a faint star and the nebula more a thumbprint smear of grayish-white light. If you have trouble spotting M1 where you think it should be, try shifting your gaze to the edge of your eyepiece without physically moving your telescope. The nebulas soft glow may pop out in your peripheral vision; this is called averted vision, and it helps because the light-sensitive cells in your eye are located on the sides, while the color-sensing cells (which need more light to register an object) are in the center. Thus, looking directly at faint objects can make them more difficult to see.

Come back to this field over the next several nights to watch Vesta move slowly west-northwest, sliding due south of M1 on the 12th.

Sunrise: 7:22 A.M. Sunset: 4:53 P.M. Moonrise: 7:00 A.M. Moonset: 3:49 P.M. Moon Phase: Waning crescent (1%)

Thursday, January 11 New Moon occurs at 6:57 A.M. EST, leaving the heavens dark and perfect for deep-sky observing.

Lets look to Monoceros the Unicorn tonight, which houses the Rosette Nebula. Youll find the Rosette some 50 high in the south by 10 P.M. local time; it sits just 2 east of magnitude 4.4 Epsilon () Monocerotis. The Rosette itself stretches more than 1 across and surrounds the young star cluster NGC 2244. The cluster has a collective magnitude of 4.8, making it an easy target: Even a small scope from a dark site should show more than two dozen stars. Moving to larger apertures will increase this number to more than 100 young suns.

But what about the Rosette? This gaseous, petal-like gas complex is made up of several different regions, all sporting different catalog numbers. As a whole, the Rosette is best seen with a large telescope (10 inches or more) and lower magnification (around 50x). Use an OIII or nebula filter to cut down on the stars brightness and bring out the nebulas gauzy glow. Alternatively, smaller apertures can work well when coupled with a camera stacked or long exposures will help reveal what the eye cannot see in smaller instruments.

Sunrise: 7:22 A.M. Sunset: 4:55 P.M. Moonrise: 7:56 A.M. Moonset: 5:04 P.M. Moon Phase: New

Friday, January 12 Mercury reaches its greatest western elongation from the Sun at 10 A.M. EST, when it is 24 from our star. Check out the planet an hour before sunrise, where it now stands 11.7 east of Venus in the southeastern sky. Through your telescope, youll notice that Mercurys illuminated face has grown from earlier in the week its now 63 percent lit and magnitude 0.2, just slightly brighter than the last time we observed it.

Venus now sits level with Antares, 9to the left (east-northeast) of the red giant star. There are several other bright stars visible in the early-morning sky as well, lingering until the impending sunrise blots them from view. Altair, Lyra, and Deneb the stars of the Summer Triangle are rising in the east, to the left of Venus and Mercury. Vega is highest, with Deneb to its lower left and Altair to its lower right, closest to the horizon. Far above Venus and just slightly to the right is Arcturus in Botes; to the lower right of this star is Spica in Virgo.

Sunrise: 7:21 A.M. Sunset: 4:56 P.M. Moonrise: 8:42 A.M. Moonset: 6:23 P.M. Moon Phase: Waxing crescent (2%)

Sky This Week is brought to you in part by Celestron.

Excerpt from:

The Sky This Week from January 5 to 12: Visitors to the Scorpion - Astronomy Magazine

New scientific results from the Atacama Large Millimeter/submillimeter Array (ALMA), the Very Large Array (VLA), and Green Bank Observatory (GBO) will be revealed at multiple press conferences during the 243rd meeting of the American Astronomical Society (AAS) from January 8-11, in New Orleans, Louisiana.

The AAS meeting includes a series of press conferences based on a range of themes. Presentations will highlight new research, including new types of planet and star formation, and the accidental discovery of a primordial galaxy.

Press conferences will be held in person during the conference, and streamed live on the AAS Press Office Page.

Note: Each press conference consists of a panel of scientists presenting 4-5 unique scientific results. The number listed in parentheses indicates the order of presentation for the listed result.

All press conferences are listed and will occur in Central Time.

Monday, 8 January 2024, 10:15 am CT Dust, Clouds & Darkness

A Polarized Dust Ring in the Milky Ways Center Natalie Butterfield (NRAO) (1)

Mystery of Star Formation Revealed by Hearts of Molecular Clouds Jin Koda (Stony Brook University) & Amanda Lee (U.Mass. Amherst) (3)

The Dark Galaxy J0613+52 Karen ONeil (Green Bank Observatory) (4)

Monday, 9 January 2024, 2:15 pm CT High-Energy Phenomena and Their Origins

Evolution of Planetary Disk Structures Seen for the First Time Cheng-Han Hsieh (Yale University) (3)

Tuesday, 9 January 2024, 2:15 pm CT High-Energy Phenomena and Their Origins

Spatially-resolved spectroscopy of dual quasars at cosmic noon with JWST and ALMA Yuzo Ishikawa (Johns Hopkins University) (1)

Wednesday, 10 January 2024, 10:15 am CT

A New Census of Neutral Clouds in the Milky Ways Nuclear Wind Jay Lockman (Green Bank Observatory)

Wednesday, 10 January 2024, 2:15 pm CT Stars, Disks & Exoplanets

JWSTs New View of Beta Pictoris Suggests Recent Episodic Dust Production from an Eccentric, Inclined Secondary Debris Disk

Christopher Stark (NASA Goddard) (3)

Thursday, 11 January 2024, 2:15 pm CT Oddities in the Sky

The Smith Cloud: A Dust Bowl Barreling Through Our Galactic Halo Johanna Vazquez (Texas Christian University) (3)

For embargo access for members of the press, please contact Jill Malusky at jmalusky@nrao.edu or Corrina Jaramillo Feldman at cfeldman@nrao.edu.

NRAO Media Contacts

Corrina C. Jaramillo Feldman Public Information Officer New Mexico VLA, VLBA, ngVLA Tel: +1 505-366-7267 cfeldman@nrao.edu

Jill Malusky NRAO & GBO News & Public Information Manager Tel: +1 304-460-5608 jmalusky@nrao.edu

In addition to the press conferences, dozens of papers with new and ongoing science results from NRAO and GBO facilities will be presented during AAS 243 conference sessions. Highlights will be posted to the NRAO website, the GBO website, and social media.

About NRAO

The National Radio Astronomy Observatory (NRAO) is a facility of the National Science Foundation, operated under a cooperative agreement by Associated Universities, Inc.

About Green Bank Observatory

The Green Bank Observatory is a facility of the National Science Foundation and is operated by Associated Universities, Inc.

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AAS 243 NRAO Press Announcement - National Radio Astronomy Observatory

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Download this detailed sky guide to discover what 2024 has in store for skywatchers: bright planets, bright comets, and a U.S. solar eclipse.

Cover credit: Astronomy magazine; Image credit: Alan Dyer

2024 is an exciting year for skywatchers.

Mercury makes several appearances this year, thanks to its 88-day orbit. The best of the bunch comes in the first week of September, when the world climbs highest above the eastern horizon before dawn. It appears nearly as good on mornings in early January and late December. If you want to see it at dusk, your best chance comes in the latter half of July.

Venus shines brilliantly before dawn from New Years Day until March. It then disappears in the Suns glow before returning to view at dusk in the latter half of July. And although Mars begins the year lost in the Suns glare, it reappears before dawn in late January and grows more prominent as the year progresses especially in autumn and winter.

Jupiter appears best around opposition in early December, though its a fine sight all year except in the weeks around solar conjunction in May. And Saturn provides a thrill for telescope owners from April through December, peaking in early September.

The years hallmark event is sure to be the April 8 total solar eclipse across North America. The stunning scene will play out wherever clear skies grace the path of totality, which begins on the Pacific Coast at Mazatln, Mexico, before heading northeast, crossing into the U.S. in Texas and then making its way to New England and the Canadian Maritimes.

2024 also brings us both a penumbral (March 25) and a partial (Sept. 17) lunar eclipse, as well as an annular solar eclipse Oct. 2. Annularity crosses Chile and Argentina, including Chiles Easter Island, where you can join Astronomy Editor David Eicher on the eclipse trip of a lifetime.

Meteor observing will suffer a bit of a down year, though the Eta Aquariids and Perseids should put on fine shows.

Finally, keep an eye to the sky for several promising comets in 2024, including C/2021 S3 (PANSTARRS), 62P/Tsuchinshan, and 144P/Kushida early in the year, followed by 12P/Pons-Brooks in spring and C/2023 A3 (Tsuchinshan-ATLAS) in the fall.

Check out our comprehensive Sky Guide 2024 below for more details on these and many more events to watch this year!

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Your guide to the sky in 2024 - Astronomy Magazine

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While telescopes are popular for stargazing, binoculars for astronomy offer a more portable option for gazing into the heavens. Binoculars are extremely versatile, working well for general terrestrial observations as well as more celestial surveying. You can even use them handheld or on a mount. Whether you want to observe the moon or casually stargaze, the best binoculars for astronomy are great to take into nature and bring you closer to the stars.

Binoculars for astronomy require more specific specs than general-purpose binoculars, so we prioritized options with larger objective lens size and higher magnification. We also aimed to select options at various price points suitable for everyone from beginners to expert stargazers. While binoculars with image stabilization are excellent for astronomy use, they are quite expensive, so weve included models both with and without stabilization. In making our selections, we considered optical quality, size and weight, eye relief, and build quality.

Binoculars for astronomy will allow you to gaze up at the moon, spot deep space objects, check out planets, and more. While these advanced optics can be used handheld, wed recommend a tripod or mount of some variety to offer more stable, high-quality night sky views.

Specs

Pros

Cons

Canon makes some of the best image-stabilized binoculars available, so it should be no surprise that our top pick comes from the imaging giant. The Canon 1236 IS III binoculars for astronomy offer the companys typical high-end optics and Porro II prisms, resulting in a sharp, bright, colorful image. It also features a double field flattener, which produces a distortion-free image.

The 36mm objective lens diameter is slightly lower than what is typically recommended for astronomy use. However, these still offer plenty of light gathering for stargazing. Youll also be able to use them for things like bird watching, adding to their versatility. Plus, the smaller objective lens results in a more compact size ideal for most people, which is why it earned our top spot. These Canon binos provide 12x magnification, allowing you to see details on the moons surface.

What really makes these optics stand out is the image stabilization. Canon built these with technology similar to what they use in their EF lenses, resulting in much sharper images when holding the binoculars. Youll need two AA batteries for power, and they will typically get up to 12 hours of use. Simply put, once you use IS binoculars, you wont want to go back to anything else.

Specs

Pros

Cons

If money is no object and you want the best of the best, the Canon 1042 L IS WP binoculars are the way to go. These powerful binoculars for astronomy offer a large objective lens of 42mm, capturing tons of light for viewing even dim celestial objects. The 10x magnification is plenty for most astronomical observations and offers plenty of eye relief for a range of users.

Like the pair mentioned above, these feature Canons impressive image stabilization. It will almost look like you are using a tripod, giving you sharp, clear views. The L in the name refers to Canons top-tier line of optics. These feature two ultra-low dispersion (UD) lens elements (on each side), which effectively corrects for chromatic aberration. Images will be sharp, bright, and vibrant, offering excellent views of the stars.

Of course, there are downsides to these binos. First, they are expensive. If you are a casual user, they will be overkill. Second, they are fairly bulky and heavy. You likely wont want to hold them for long periods, and they will add weight to your pack if you are hiking. But this is the pair to get if you are serious about stargazing with your binoculars.

Specs

Pros

Cons

Celestron is one of the top telescope producers, so it makes sense that the company would also produce top-notch binoculars for astronomy. Celestron SkyMaster 25100 is essentially the equivalent of a telescope in your hands. It offers a whopping 25x magnification and an objective lens measuring 100mm. That massive lens will let in tons of light. Paired with the high level of magnification, youll see epic details in the night sky, such as Jupiters belts, star clusters, and more.

These binos feature BaK-4 prisms and multi-coated lenses, enhancing contrast for superb viewing quality. They are ruggedly built with a water-resistant design. The SkyMaster also utilizes a rubber-armored housing, which protects them from damage and provides a better grip.

Unfortunately, such power comes with great responsibility. In this case, that means lots of weight. The SkyMaster weighs 8.75 pounds and, naturally, is larger than any other option on our list. They also dont offer any image stabilization. As a result, you wont want to hold these by hand for very long. Luckily, it has a built-in tripod adapter, making it easier to hook up to a tripod for hands-free use. All of this also comes at a rather reasonable price, so you dont have to break the bank to see craters on the moon.

Pros

Cons

Weight is an important consideration when backpacking or hiking, even when you hope to take advantage of the dark skies. Thats where the Nikon PROSTAFF P7 binoculars come into play. They are very compact and lightweight, coming in at just 1.3 pounds and just under six inches long. It will be much easier to bring them along on your trips. And, it will be easier to hold for longer viewing sessions as well.

The PROSTAFF P7 are also ruggedly built and suited for adventures. They are waterproof to 3.3 feet and nitrogen-filled for fogproof performance. The 0.62-inch eye relief works well for those who wear glasses, and the turn-and-slide eyecups are adjustable to work well for a group of people. A rubber-armored body protects from drops and bumps and makes them easier to hold. Nikon used a water- and oil-repellent coating on both the objective and eyepiece lenses, which helps keep them free of water and fingerprints.

Although these are not specifically designed for stargazing, they will definitely do the job. The 10x magnification is enough for casual night sky viewing, and the 42mm objective lens will gather plenty of light. Nikon designed these with high-quality optics and Phase-Correction coating for superb image quality and clarity. It also features a dielectric high-reflective multilayer prism coating, which maximizes light transmission. Finally, the locking diopter ring, typically only found on much more expensive optics, keeps your setting locked in.

Specs

Pros

Cons

You dont have to spend a fortune to get started with binoculars for astronomy. This budget-friendly pair also happens to be great for beginner stargazers. They are compact and lightweight, making them ideal binoculars for hiking. Yet they still offer 10x magnification and a 50mm objective lens. Those specs will allow you to see the moon in all its glory easily, as well as some star clusters and more.

Celestron built these with a rugged design, including a rubber coating to protect from drops and improve grip. They are water resistant, so you wont need to panic if you get caught in a rain shower. They are not nitrogen-filled, though, so they tend to fog up.

The main downside to this budget set of binos is that they require collimationthe alignment of the lenses. While not difficult, it does take time away from your stargazing. The good news is that Celestron used multi-coated optics, which results in a quality image with good contrast and mostly accurate color. If you are just getting started or want some kid-friendly binoculars for astronomy, these will do a great job.

Binoculars are, for the most part, rather simple devices without much in the way of fancy technology. But, there is some specific lingo that you should be aware of when shopping for binoculars for astronomy to ensure you pick the right optics for viewing the night sky.

All binoculars include two numbers in the name, such as 1050. The first number refers to magnification. For stargazing, youll typically want at least 10x magnification. If you want to see the moon or planets in more detail or search for smaller deep space objects, 12x will be better. However, remember that more magnification will exaggerate movement while holding the binoculars. So, if you will only handhold the binos, we suggest sticking to 10x or lower.

The second number tells you the size of the objective lens, measured in millimeters. In our example above, that would be 50mm. The objective lens is the lens closest to the object youre viewing, or the one opposite of the eyepieces. This number tells you how large the binoculars are and how much light they let in.

Larger objective lenses collect more light, which is better for stargazing. But it also means larger binoculars, which makes them harder to handhold. As a result, youll need a balance unless you only plan on using a tripod or mount of some type. For astronomy use, youll want at least 40-50mm, though 50-60mm will allow you to see fainter celestial objects.

If youve ever spent time looking through binoculars, you may have noticed how hard it is to keep them steady. That movement gets even more dramatic in higher-powered binoculars for astronomy, which can make detailed observations quite challenging. If you want superb image quality and dont always want to rely on a tripod, look for a pair of image-stabilized binoculars.

There are different types of image stabilization in binos. Some offer passive stabilization (also called mechanical stabilization) with suspended prisms, which dont require any batteries. Other types of stabilization include digital, optical, and hybrid stabilization (a combination of digital and optical). Each type has pros and cons, though hybrid stabilization offers the best results, albeit at the highest cost.

There are two varieties of binocular design: Roof prisms and Porro prisms. In Porro prism binoculars, the objective lens is offset from the eyepiece, requiring the light to travel in a zig-zag pattern. This design can result in a higher quality image, but they are bulky and heavy compared to roof prism binos.

The prisms in Roof prism binoculars line up closely, allowing the objective lens to be in a straight line from the eyepiece. The Roof prism design results in a more compact, lightweight form factor. However, it is a more complicated design, which results in a much higher price tag compared to Porro prism binoculars.

Exit pupil refers to the round, bright image you see when looking through the eyepiece. The larger the diameter, the brighter the image, which is important for astronomy. To calculate this, divide the objective lens diameter by the magnification. So, for example, a 1050 binocular would offer an exit pupil of 5mm.

The key here is to find binoculars for astronomy with an exit pupil roughly the same size as the human pupil when dilated for darkness. In dark conditions, most pupils dilate to around 7mm. Opting for binoculars with an exit pupil of 2.5mm will make the image look quite dark.

Eye relief is the distance from the eyepiece lens to the exit pupil, where the image is formed. Put simply, it is how far you can hold the binoculars away from your eyes and still see the full image without vignetting. If you wear glasses, youll need binoculars with longer eye relief. Be sure to go with an eye relief greater than 14mm if you use glasses.

Weight might not be the first thing that comes to mind when choosing binoculars for astronomy. However, it can be incredibly important. If you plan on handholding your binoculars, look for a more compact, lightweight option. Otherwise your arms will tire quickly, but more importantly, they will be hard to hold steady. And if you cant hold them steady, you wont get a very good view of the night sky.

If you opt for a heavier option or plan long observation sessions with high magnification, we recommend mounting the binoculars to a tripod.

Binoculars with 10x magnification and an objective lens of 50mm (1050) are the most popular option for astronomy, thanks to the balance of size and magnification. However, if you want to see objects in more detail or hope to view faint deep space objects, something like 1570 or larger is best.

Depending on the objective lens and magnification on your binoculars, youll be able to use them to view the moon, planets, star clusters, nebulae, and even some galaxies.

While you can certainly look up at the stars with any binoculars, not just any pair will allow for in-depth astronomy. For astronomy use, youll need optics that are able to gather plenty of light and offer higher magnification than general use. Budget and travel-friendly binoculars typically wont make the cut as a result.

How much you should spend on binoculars for astronomy depends on how you plan on using them and what you hope to view. For beginners, a few hundred dollars is plenty. For those wanting epic night sky views, youll want to spend closer to $1,000 for high-quality optics, impressive image stabilization, and plenty of light-gathering abilities.

Binoculars for astronomy can serve as an excellent alternative to bulky telescopes. These optics allow you to view celestial objects on the go, making it a great choice for camping, hiking, or travel of any type. Binoculars are also easier to store, which is ideal for those living in smaller spaces. Despite their convenience, they still allow you to see plenty of wonders in the night sky.

Popular Science started writing about technology more than 150 years ago. There was no such thing as gadget writing when we published our first issue in 1872, but if there was, our mission to demystify the world of innovation for everyday readers means we would have been all over it. Here in the present, PopSci is fully committed to helping readers navigate the increasingly intimidating array of devices on the market right now.

Our writers and editors have combined decades of experience covering and reviewing consumer electronics. We each have our own obsessive specialtiesfrom high-end audio to video games to cameras and beyondbut when were reviewing devices outside of our immediate wheelhouses, we do our best to seek out trustworthy voices and opinions to help guide people to the very best recommendations. We know we dont know everything, but were excited to live through the analysis paralysis that internet shopping can spur so readers dont have to.

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The best binoculars for astronomy in 2024 - Popular Science

A telescope scans the sky in search of signals sent from advanced alien civilizations in this artist's concept. Credit: paulista/Shutterstock.

Dont bother wondering if alien civilizations can hear our radio broadcasts or not. According to a new study, sufficiently advanced aliens can already see us.

The research, set to be published to the journal Acta Astronomica, starts with a very basic assumption: that the laws of physics as we currently understand them are largely correct and hold across the universe. While this might not be true, anything past that assumption would be largely groundless speculation, so its as good a starting point as any.

This assumption allows us to conclude that if an alien civilization wants to directly observe us, then theyre going to need a big telescope. Us humans have built a variety of large structures on and around our planet, like the great pyramids, skyscrapers, and spacecraft (the authors did not discuss larger, more visible signs of technological development, like roads, canals, and farms). If aliens had a similar level of technology to ourselves, they might detect something funny in the spectrum of light coming from the Earth, but their image of our planet would be just a tiny dot. If they really wanted to see if we were up to something interesting, they would need a lot more resolution.

In astronomy to get more resolution we need bigger optics. To have the resolving power to take a picture of the pyramids, however, an alien civilization sitting hundreds of thousands of light-years away will need a telescope roughly ten times greater than the orbit of the Earth. This is an understandably daunting task, even for highly advanced aliens, so instead they can opt for a technique called long-baseline interferometry, where astronomers send multiple telescopes very far from each other and observe the same target, combining the data later to make a coherent image.

Earth astronomers have had great success using this technique at radio wavelengths, but we do not have the technological sophistication necessary to apply the technique to visible wavelengths of light, because we cannot record the information fast enough. But advanced aliens might just be able to do the trick, according to the researchers.

Aliens can only see what weve built after weve already built it, and it takes time for those light signals from our constructions to make their way out into the cosmos. That sets an upper limit on the distance of our visibility to any other civilization. For example, the great pyramids of Giza were built roughly 3,000 years ago, and so aliens have to be within 3,000 light-years to be able to see them. Similarly, aliens farther than roughly 100 light-years cant see our skyscrapers, and farther than a few tens of light-years couldnt pick out our orbiting space stations.

So the question of our visibility becomes whether a sufficiently advanced civilization sits within any of those bubbles.

Life may or may not be common in the universe. At the present time we have no evidence whatsoever of any life existing outside the Earth, so we can only guess. Presumably, and this is only a guess, intelligence is even rarer than life. And sophisticated intelligence is even rarer. The Kardashev scale gives us a sense of different levels of sophistication of a species, and from there we can estimate how common those levels are.

For example, a Kardashev Type-I civilization can harness the energy equivalent to the total solar energy hitting their planets surface. The authors of the paper argue that such a civilization could not construct a powerful enough telescope, so even if theyre nearby, they wont see us.

Next up the ladder is a Type-II civilization, which can use all the energy output of a typical star. These civilizations just might have the sophistication to directly observe us from hundreds or thousands of light-years away, but they are probably much rarer than their less sophisticated cousins.

Our visibility comes down to the number of Type-II civilizations nearby. If, for example, there are millions of such civilizations currently inhabiting the Milky Way, then conceivably one of them could be within the bubble of a few thousand light-years, and they could, at this very moment, be watching as the ancient Egyptians build their first pyramids.

If advanced civilizations are less common, however, then the average distance between intelligent aliens is so large that even the nearest one likely sits outside out visibility bubble, and they dont know yet that intelligent creatures have started large-scale engineering projects on the Earth. Theyre just going to have to wait.

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Are we visible to alien astronomers? This study makes the case - Astronomy Magazine

An international team of astronomers has revealed mysterious star formation at the far edge of the galaxy M83. This research was presented today in a press conference at the 243rd meeting of the American Astronomical Society (AAS) in New Orleans, Louisiana.

The research used several instruments operated by the National Science Foundations National Radio Astronomy Observatory (NRAO), including the Atacama Large Millimeter/submillimeter Array (ALMA), the Karl G. Jansky Very Large Array (VLA), and the Green Bank Telescope (GBT), along with the National Astronomical Observatory of Japans (NAOJ) Subaru Telescope and the NASA Galaxy Evolution Explorer (GALEX).

Normally, new stars form as a result of diffuse atomic gas shrinking into concentrations of molecular gas, called molecular clouds, whose high density cores at their center trigger star formation. This process is common in the inner part of galaxies, but becomes increasingly rare toward galaxy outskirts.

A surprising number of very young stars are known to exist at the far edges of many galaxies, but scientists could not understand how and why these stars were made, because they could not pinpoint their formation sites. This research discovered 23 molecular clouds that showed a different type of star formation. The large bodies of these clouds were not visible like normal molecular cloudsonly their star-forming dense cores, the hearts of the clouds, were observed. This discovery provides an important clue to understanding the physical processes that lead to star formation in general.

The star formation at galaxy edges has been a nagging mystery since their discovery by the NASA GALEX satellite 18 years ago said astronomer Jin Koda, of Stony Brook University, who led this research, Previous searches for molecular clouds in this environment turned out unsuccessful. David Thilker, of Johns Hopkins University, who originally discovered the star formation activity occurring in the outskirts of M83 and other galaxies, commented, It has been gratifying to see the search for dense clouds associated with the outer disk finally come to fruition, revealing a characteristically different observational fingerprint for the molecular clouds.

The revelation of these molecular clouds uncovered a link to a large reservoir of diffuse atomic gas, another discovery by this research. Normally, atomic gas condenses into dense molecular clouds, within which even denser cores develop and form stars. This process is in operation even at galaxy edges, but the conversion of this atomic gas to molecular clouds was not evident, for reasons that are yet unresolved.

Amanda Lee, who was an undergraduate student on Kodas research team, processed GBT & VLA data for these findings. Through this, she discovered the atomic gas reservoir at the galaxy edge. We still do not understand why this atomic gas does not efficiently become dense molecular clouds and form stars. As often is the case in astronomy, pursuing answers to one mystery can often lead to another. Thats why research in astronomy is exciting, adds Lee, who is now pursuing her Ph.D. in astronomy at UMass Amherst.

Thilker added, I am excited to see this new opportunity leveraged more broadly in the outer disk environment in order to gain a deeper insight for physical processes central to the inside-out growth of galaxies still happening in the current cosmic epoch.

When I started, I didnt know what role my work would play. It was very exciting to see it contribute to the big picture of star formation, said Lee.

Watch the press conference here.

About ALMA & NRAO

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

NRAO is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

About Green Bank Observatory

The Green Bank Observatory is a major facility of the National Science Foundation and is operated by Associated Universities, Inc. The first national radio astronomy observatory in the US, its home to the 100-meter Green Bank Telescope, the largest fully-steerable radio telescope in the world.

###

Corrina Jaramillo Feldman, Public Information Officer NRAO/VLA/ngVLA

cfeldman@nrao.edu

505-366-7267

Jill Malusky, NRAO & GBO News & Public Information Manager

jmalusky@nrao.edu

304-460-5608

Read more here:

Mystery of Star Formation Revealed by Hearts of Molecular Clouds - National Radio Astronomy Observatory