Meteors Archives

May 20, 2014December 23, 2015 by Bob King

How to See 209P/LINEAR, the Comet Brewing Up Saturday’s Surprise Meteor Shower

Comet 209P/LINEAR may still be faint but it's a beautiful object in this time exposure by Austrian astrophotographer Michael Jaeger. The stars appear as trails because the photographer followed the comet during the exposure.

As we anxiously await the arrival of a potentially rich new meteor shower this weekend, its parent comet, 209P/LINEAR, draws ever closer and brighter. Today it shines feebly at around magnitude +13.7 yet possesses a classic form with bright head and tail. It’s rapidly approaching Earth, picking up speed every night and hopefully will be bright enough to see in your telescope very soon.

As it approaches Earth in the coming nights, comet 209P/LINEAR will appear to move quickly across the sky, traveling from Leo Minor to southern Hydra in little over a week. All maps created with Chris Marriott's SkyMap software — As it approaches Earth in the coming nights, comet 209P/LINEAR will move quickly across the sky, traveling from Ursa Major to southern Hydra in just 10 days. When closest on May 28-29, the comet will cover 10 degrees per day or just shy of 1/2 degree per hour. All maps created with Chris Marriott’s SkyMap software

The comet was discovered in Feb. 2004 by the Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) automated sky survey. Given its stellar appearance at the time of discovery it was first thought to be an asteroid, but photos taken the following month photos by Rob McNaught (Siding Spring Observatory, Australia) revealed a narrow tail. Unlike long period comets Hale-Bopp and the late Comet ISON that swing around the sun once every few thousand years or few million years, this one’s a frequent visitor, dropping by every 5.09 years.

This detailed map shows the comet's path from Leo Minor across the backside of the Sickle of Leo May 23-26. Hopefully it will be bright enough then to spot in an 8-inch or larger telescope. Click to enlarge and then print out for use at the telescope. — This detailed map shows the comet’s path from Leo Minor across the backside of the Sickle of Leo May 23-26. Hopefully it will be bright enough then to spot in an 8-inch or larger telescope. On May 25, it passes close to the colorful double star Gamma Leonis and a pair of NGC galaxies. Stars plotted to magnitude +9. Click to enlarge and then print out for use at the telescope.

209P/LINEAR belongs to the Jupiter family of comets, a group of comets with periods of less than 20 years whose orbits are controlled by Jupiter. When closest at perihelion, 209P/LINEAR coasts some 90 million miles from the sun; the far end of its orbit crosses that of Jupiter. Comets that ply the gravitational domain of the solar system’s largest planet occasionally get their orbits realigned. In 2012, during a relatively close pass of that planet, Jupiter perturbed 209P’s orbit, bringing the comet and its debris trails to within 280,000 miles (450,000 km) of Earth’s orbit, close enough to spark the meteor shower predicted for this Friday night/Saturday morning May 23-24.

Track of the comet through from May 27-29 through the dim constellation Sextans south of Leo. — Track of the comet from May 27-29 through Sextans to the Hydra-Crater border with positions shown every 3 hours. Times are CDT. Click to enlarge.

This time around the sun, the comet itself will fly just 5.15 million miles (21 times the distance to the moon) from Earth around 3 a.m. CDT (8 hours UT) May 29 a little more than 3 weeks after perihelion, making it the 9th closest comet encounter ever observed. Given , you’d think 209P would become a bright object, perhaps even visible with the naked eye, but predictions call for it to reach about magnitude +11 at best. That means you’ll need an 8-inch telescope and dark sky to see it well. Either the comet’s very small or producing dust at a declining rate or both. Research published by Quanzhi Ye and Paul A. Wiegert describes the comet’s current dust production as low, a sign that 209P could be transitioning to a dormant comet or asteroid.

Light curve for comet 209P/LINEAR predicts a maximum magnitude of around 11. Click for more information. Credit: Seiichi Yoshida — Light curve for comet 209P/LINEAR forecasts a maximum magnitude of around 11. Dates are shown along the bottom and magnitude scale along the side. Click for additional information. Credit: Seiichi Yoshida

Fortunately, the moon’s out of the way this week and next when 209P/LINEAR is closest and brightest. Since we enjoy comets in part because of their unpredictability, maybe a few surprises will be in the offing including a brighter than expected appearance. The maps will help you track down 209P during the best part of its apparition. I deliberately chose ‘black stars on a white background’ for clarity in use at the telescope. It also saves on printer ink!

A brand new meteor shower shooting 100 and potentially as many as 400 meteors an hour may radiate from the dim constellation Camelopardalis below the North Star Saturday morning May 24. Each is crumb or pebble of debris lost by 209P/LINEAR during earlier cycles around the sun. This map shows the sky facing north around 2 a.m. from the Saturday May 24 from the central U.S. Stellarium

We’re grateful for the dust 209P/LINEAR carelessly lost during its many passes in the 19th and early 20th centuries. Earth is expected to pass through multiple filaments of debris overnight Friday May 23-24 with the peak of at least 100 meteors per hour – about as good as a typical Perseid or Geminid shower – occurring around 2 a.m. CDT (7 hours UT).

If it’s cloudy or you’re not in the sweet zone for viewing either the comet or the potential shower, astrophysicist Gianluca Masi will offer a live feed of the comet at the Virtual Telescope Project website scheduled to begin at 3 p.m. CDT (8 p.m. Greenwich Time) May 22. A second meteor shower live feed will start at 12:30 a.m. CDT (5:30 a.m. Greenwich Time) Friday night/Saturday morning May 23-24.

SLOOH will also cover 209P/LINEAR live on the Web with telescopes on the Canary Islands starting at 5 p.m. CDT (6 p.m. EDT, 4 p.m. MDT and 3 p.m. PDT) May 23. Live meteor shower coverage featuring astronomer Bob Berman of Astronomy Magazine begins at 10 p.m. CDT. Viewers can ask questions by using hashtag #slooh.

A very exciting weekend lies ahead!

May 19, 2014December 23, 2015 by David Dickinson

Can You Say Camelopardalids? Observing, Weather Prospects and More for the May 24th Meteor Shower

It could be the best of meteor showers, or it could be the…

Well, we’ll delve into the alternatives here in a bit. For now, we’ll call upon our ever present astronomical optimism and say that one of the best meteor showers of 2014 may potentially be on tap for this weekend.

This is a true wild card event. The meteor shower in question hails from a periodic comet 209P LINEAR discovered in 2004 and radiates from the obscure and tongue-twisting constellation of Camelopardalis.

But whether you call ‘em the “209/P-ids,” the “Camelopardalids,” or simply the “Cams,” this weekend’s meteor shower is definitely one worth watching out for. The excitement surrounding this meteor shower came about when researchers Peter Jenniskens and Esko Lyytinen noticed that the Earth would cross debris streams laid down by the comet in 1803 and 1924. Discovered by the LIncoln Near-Earth Asteroid Research (LINEAR) automated all-sky survey located at White Sands, New Mexico, comet 209P LINEAR orbits the Sun once every 5.1 years. 209P LINEAR passed perihelion at 0.97 AUs from the Sun this month on May 6^th.

Looking north from latitude +30N at 7:00 UT on the morning of May 24th. Created using Starry Night.

The meteor shower peaks this coming U.S. Memorial Day weekend on Saturday, May 24^th. The expected peak is projected for right around 7:00 Universal Time (UT) which is the early morning hours of 3:00 AM EDT, giving North America a possible front row seat to the event. Estimates for the Zenithal Hourly Rate (ZHR) of the Camelopardalids run the gamut from a mild 30 to an outstanding 400 per hour. Keep in mind, this is a shower that hasn’t been witnessed, and it’s tough enough to forecast the timing and activity of known showers. It’s really a question of how much debris the 1803 and 1924 streams laid down on those undocumented passages. One possible strike against a “meteor storm” similar to the 1998 Leonids that we witnessed from Kuwait is the fact that the “Cams” have never been recorded before. Still, you won’t see any if you don’t try!

Cams — The orientation of the Earth, the day/night terminator, the Sun, Moon and radiant of the meteor shower on May 24th at 7:00 UT. Created by author.

Comet 209P/LINEAR passes 0.055 AUs — about 8.3 million kilometres — from the Earth on May 29^th, shining at +11^th magnitude and crossing south into the constellation of Leo Minor in late May. Interestingly, it also passes 0.8 degrees from asteroid 2 Pallas on May 26^th. Though tiny, comet 209P/LINEAR’s 2014 passage ranks as the 9^th closest recorded approach of a comet to the Earth.

The Moon is also at an ideal phase for meteor watching this coming weekend as it presents a waning crescent phase just 4 days from New and rises at around 4:00 AM local.

The expected radiant for the Cams sits at Right Ascension 8 hours and declination 78 degrees north in the constellation of Camelopardalis, the “camel leopard…” OK, we’ve never seen such a creature, either. (Read “giraffe”). Unfortunately, this puts the radiant just 20 degrees above the northern horizon as seen from +30 degrees north latitude here in Florida at 7:00 UT. Generally speaking, the farther north you are, the higher the radiant will be in the sky and the better your viewing prospects are. Canada and the northern continental United States could potentially be in for a good show. Keep in mind too, the high northern declination of the radiant means that it transits the meridian (crosses upper culmination) a few hours before sunset Friday night at 6 PM local; this means it’ll have an elevation of about 38 degrees above the horizon as seen from 30 degrees north latitude just after sunset. It may well be worth watching for early activity after dusk!

Weather — A look ahead at the cloud cover prospects for the morning of May 24th. Credit: NOAA.

Clouded out or live on the wrong side of the planet to watch the Camelopardalids? Slooh will be carrying a live broadcast of the event starting at 3:00 PM PDT/ 6:00 PM EDT/ 22:00 UT. Also, the folks at the Virtual Telescope Project will carry two separate webcasts of the event, one featuring the progenitor comet 209P LINEAR starting at 20:00 UT on May 22^nd and another featuring the meteor shower itself starting at 5:30 UT on May 24^th.

Observing meteors is fun and easy and requires nothing more than a good pair of “mark-1 eyeballs” and patience. And although the radiant may be low to the north, meteors can appear anywhere in the sky. We like to keep a pair of binocs handy to examine any lingering smoke trains left by bright fireballs. Counting the number of meteors you see from your location and submitting this estimate to the International Meteor Organization may help in ongoing efforts to understand this first time meteor shower. And capturing an image of a meteor is as simple as setting a DSLR on a tripod with a wide field of view and taking time exposures of the sky… something you can start practicing tonight.

P_20140518_110518 — Our humble meteor observing rig… (Photo by author).

Don’t miss what could well be the astronomical event of the year… I’d love to see a meteor shower named after an obscure constellation such as the #Camelopardalids trending. And we fully expect to start fielding reports of “strange rocks falling from the sky” this week, which the cometary dust that composes a meteor shower isn’t. In fact, Meteorite Man Geoffrey Notkin once noted that no confirmed meteorite fall has ever been linked to a periodic meteor shower.

Don’t miss the celestial show!

-Got pics of the Camelopardalids? Send ‘em to Universe Today. There’s a good chance that we’ll run an after-action photo-round up if the Cams kick it into high gear.

-Read more about the Camelopardalids here in a recent outstanding post by Bob King on Universe Today.

May 5, 2014December 23, 2015 by Nancy Atkinson

Dashcams, Tweets Show Bright Daytime Fireball Over Ontario, Canada on May 4

The likely trajectory of the fireball seen on May 4, 2014 over parts of Ontario Canada. Graphic courtesy American Meteor Society.

A rare daylight meteor streaked across the skies over southern Ontario, Canada and the U.S. Northeast during the afternoon of Sunday May 4, 2014, with brightness “rivaling that of the Sun,” said the American Meteor Society. Reports of a bright fireball followed by a loud sonic boom were reported on social media, and several dashcam videos emerged showing the fireball, showing an unusual vertical trajectory.

Experts estimated the space rock that caused the excitement as being about half to one meter in diameter and exploding with a force of 50 tons of TNT energy. Canadian meteor expert Peter Brown, a professor at the University of Western Ontario said in the Winnipeg Free Press that he is confident that the fireball was large enough that some meteorite fragments may have hit the ground. .

Compared to the meteor that exploded over Chelyabinsk, Russia in February of 2013, that’s quite small. That meteor’s explosion shattered windows and injured 1,000 people.

See more videos, tweets and images below, and you can read a liveblog of the event (with lots of links) by Daniel Fischer (@cosmos4u).

Taken in Port Hope, ON at 4:20 pm. Looked like meteor exploding. Heard BOOM. Then rumble. Ground shook #meteor pic.twitter.com/RQfZ7r55Do

— DC-Photography (@DCPhotographyON) May 5, 2014

Here's the photo of the #meteor contrail over GTA and Durham! Saw this from Whitby…. Seeing this made my day pic.twitter.com/gINzrFeMc9

— Veronica (@iVeronica) May 4, 2014

Sonic boom you felt. RT @island_gurl75: #meteor strikes or explodes near #Peterborough. We felt 4 big bangs, felt like a car hit the house!

— Dënnis (@DennisOBrienJr) May 4, 2014

Read more news reports at the American Meteor Society, Globe and Mail, and Global News.

May 4, 2014December 23, 2015 by Bob King

Revisit Halley’s Comet – Stay Up Late for This Week’s Eta Aquarid Meteor Shower

The Eta Aquarid meteor shower is active in early May and peaks before dawn on Tuesday and Wednesday May 6-7 this year. Watch for it before the start of morning twilight in the eastern sky. Created with Stellarium

UPDATE: Watch a live webcast of the meteor shower, below, from NASA’s Marshall Space Flight Center during the night of Monday, May 5 to the early morning of May 6.

Halley’s Comet won’t be back in Earth’s vicinity until the summer of 2061, but that doesn’t mean you have to wait 47 years to see it. The comet’s offspring return this week as the annual Eta Aquarid meteor shower. Most meteor showers trace their parentage to a particular comet. The Perseids of August originate from dust strewn along the orbit of comet 109P/Swift-Tuttle, which drops by the inner solar system every 133 years after “wintering” for decades just beyond the orbit of Pluto, but the Eta Aquarids (AY-tuh ah-QWAR-ids) have the best known and arguably most famous parent of all – Halley’s Comet. Twice each year, Earth’s orbital path intersects dust and rock particles strewn by Halley during its cyclic 76-year journey from just beyond Uranus to within the orbit of Venus. When we do, the grit meets its demise in spectacular fashion as wow-inducing meteors.

Video streaming by Ustream

Composite of Aquarid meteors from the 2012 shower. Credit: John Chumack

Meteoroids enter the atmosphere and begin to glow some 70 miles high. The majority of them range from sand to pebble sized but most no more than a gram or two. Speeds range from 25,000-160,000 mph (11-72 km/sec) with the Eta Aquarids right down the middle at 42 miles per second (68 km/sec). Most burn white though ‘burn’ doesn’t quite hit the nail on the head. While friction with the air heats the entering meteoroid, the actual meteor or bright streak is created by the speedy rock exciting atoms along its path. As the atoms return to their neutral state, they emit light. That’s what we see as meteors. Picture them as tubes of glowing gas.

The farther south you live, the higher the shower radiant will appear in the sky and the more meteors you’ll see. For southern hemisphere observers this is one of the better showers of the year with rates around 30-40 meteors per hour. With no moon to brighten the sky, viewing conditions are ideal. Except for maybe the early hour. The shower is best seen in the hour or two before the start of dawn.

The Eta Aquarid shower originates with material left behind by Halley's Comet when the sun boils dust and ice from its nucleus around the time of perihelion. This photo from May 1986 during its last pass by Earth. Credit: Bob King — The Eta Aquarid shower originates with material left behind by Halley’s Comet when the sun boils dust and ice off its nucleus around the time of perihelion. This photo from May 1986 during Halley’s last visit. Credit: Bob King

From mid-northern latitudes the radiant or point in the sky from which the meteors will appear to originate is low in the southeast before dawn. At latitude 50 degrees north the viewing window lasts about 1 1/2 hours; at 40 degrees north, it’s a little more than 2 hours. If you live in the southern U.S. you’ll have nearly 3 hours of viewing time with the radiant 35 degrees high.

A bright, earthgrazer Eta Aquarids streaks across Perseus May 6, 2013. Because the radiant is low for northern hemisphere observers, earthgrazers - long, bright meteors that come up from near the horizon and have long-lasting trails. Credit: Bob King — A bright, earthgrazing Eta Aquarid meteor streaks across Perseus May 6, 2013. Because the radiant is low for northern hemisphere observers, watch for earthgrazers – long, bright meteors that come up from near the horizon and have long-lasting trails. Credit: Bob King

Northerners might spy 5-10 meteors per hour over the next few mornings. Face east for the best view and relax in a reclining chair. One good thing about this event – it won’t be anywhere near as cold as watching the December Geminids or January’s Quadrantids. We must be grateful whenever we can.

Meteor shower members can appear in any part of the sky, but if you trace their paths in reverse, they’ll all point back to the radiant. Other random meteors you might see are called sporadics and not related to the Eta Aquarids. Because Aquarius is home to at least two radiants, we distinguish the Etas, which radiate from near Eta Aquarii, from the Delta Aquarids, an unrelated shower active in July and August.

Wishing you clear skies and plenty of hot coffee at the ready.

April 28, 2014December 23, 2015 by Bob King

May Meteor Storm Alert: All Eyes on the Sky!

Composite photo of Lyrid meteor shower and non-Lyrids taken with a NASA All-sky camera April 21-23, 2012. Credit: NASA/MSFC/Danielle Moser

On Friday night/early Saturday May 23-24 skywatchers across the U.S. and southern Canada may witness the birth of a brand new meteor shower. If predictions hold true, Earth will pass through multiple tendrils of dust and pebbly bits left behind by comet 209P/LINEAR, firing up a celestial display on par with the strongest showers of the year. Or better.

Peter Jenniskens of the SETI Institute, who predicted a possible meteor storm associated with comet 209P/LINEAR. Credit: NASA

Earlier predictions called for a zenithal hourly rate or ZHR of 1,000 per hour, pushing this shower into the ‘storm’ category. ZHR is an idealized number based on the shower radiant located at the zenith under ideal skies. The actual number is lower depending on how far the radiant is removed from the zenith and how much light pollution or moonlight is present. Meteor expert Peter Jenniskens of the SETI Institute and Finland’s Esko Lyytinen first saw the possibility of a comet-spawned meteor storm and presented their results in Jenniskens’ 2006 book Meteor Showers and Their Parent Comets.

Approximate location of the radiant of the 209P/LINEAR shower at the peak of the brief maximum around 2 a.m. CDT May 24. Between 100-400 meteors may radiate from the dim constellation of Camelopardalis near the North Star. This map shows the sky from Des Moines, Iowa. Created with Stellarium — Approximate location of the radiant (blue) of the 209P/LINEAR shower at the peak of the brief maximum around 2 a.m. CDT May 24. Between 100-400 meteors may radiate from the dim constellation of Camelopardalis near the North Star. This map shows the sky from the central U.S. Created with Stellarium

Quanzhi Ye and Paul Wiegert (University of Western Ontario) predict a weaker shower because of a decline in the comet’s dust production rate based on observations made during its last return in 2009. They estimate a rate of ~200 per hour.

On the bright side, their simulations show that the comet sheds larger particles than usual, which could mean a shower rich in fireballs. Other researchers predict rates between 200 and 40o per hour. At the very least, the Camelopardalids – the constellation from which the meteors will appear to originate – promise to rival the Perseids and Geminids, the year’s richest showers. Motivation for setting the alarm clock if there ever was.

Comet 209P/LINEAR on April 14, 2014. It’s currently very faint at around magnitude 17. Material shed by the comet during passes between 1898-1919 may spawn a rich meteor shower overnight May 23-24. Credit: Ernesto Guido, Nick Howes, Martino Nicolini — Comet 209P/LINEAR on April 14, 2014. It’s currently very faint at around magnitude +17. Material shed by the comet during passes from 1898-1919 is expected to contribute to a May 23-24 shower. Credit: Ernesto Guido, Nick Howes, Martino Nicolini

Comet 209P/LINEAR, discovered in Feb. 2004 by the automated Lincoln Laboratory Near-Earth Asteroid Research (LINEAR) sky survey, orbits the sun every 5.04 years with an aphelion (most distant point from the sun) near Jupiter. In 2012, during a relatively close pass of that planet, Jupiter perturbed its orbit, bringing it to within 280,000 miles (450,000 km) of Earth’s orbit.

That set up a remarkably close encounter with our planet on May 29 when 209P will cruise just 5 million miles (8 million km) from Earth to become the 9th closest comet ever observed. Multiple debris trails shed by the comet as long ago as the 18th century will intersect our planet’s path 5 days earlier, providing the material for the upcoming meteor shower/storm.

Shining meekly around magnitude +17 at the moment, 209P/LINEAR could brighten to magnitude +11 as it speeds from the Big Dipper south to Hydra during the latter half of May. Closer to the BIG night, we’ll provide helpful maps for you to track it down in your telescope. Cool to think that both the shower and its parent comet will be on display at the same time.

The shaded area shows where the shower will be visible on May 23-24. North of the red line, the moon (a thick crescent) will be up during shower maximum around 2:10 a.m. CDT. Credit: Mikhail Maslov

The shower’s expected to last only a few hours from about 12:40-3:50 a.m. CDT with the best viewing locations in the U.S. and southern half of Canada. This is where the radiant will be up in a dark sky at peak activity. A thick crescent moon rises around 3-3:30 a.m. but shouldn’t pose a glare problem.

Meteors from 209P/LINEAR are expected to be bright and slow with speeds around 40,000 mph compared to an average of 130,000 mph for the Perseids. Most shower meteoroids are minute specks of rock, but the Camelopardalids contain a significant number of particles larger than 1mm – big enough to spark fireballs.

The dark streak is a series of filaments of dust and grit left behind by 209P/LINEAR mostly between 1803 and 1924 that Earth (shown on path) will pass through on May 23-24, 2014. Credit: — The dark “finger” represents streams of dust and rocks left behind by 209P/LINEAR during passes made from 1803 to 1924. Earth is shown intersecting the debris on May 23-24, 2014. Credit: Dr. Jeremie Vaubaillon

The farther north you live in the shaded area on the map, the higher the radiant stands in the northern sky and the more meteors you’re likely to see. Skywatchers living in the Deep South will see fewer shooting stars, but a greater proportion will be earthgrazers, those special meteors that skim the upper atmosphere and flare for an unusually long time before fading out.

To see the shower at its best, find a dark place with an open view to the north. Plan your viewing between 12:30 and 4 a.m. CDT (May 24), keeping the 2 a.m. forecast peak in mind. Maximum activity occurs around 3 a.m. Eastern, 1 a.m. Mountain and midnight Pacific time.

No one’s really certain how many meteors will show, but I encourage you to make the effort to see what could be a spectacular show.

April 19, 2014December 30, 2015 by Jason Major

Echoes of Chelyabinsk: Another Fireball Explodes Over Russia

Why does Russia seem to get so many bright meteors? Well at 6.6 million square miles it’s by far the largest country in the world plus, with dashboard-mounted cameras being so commonplace (partly to help combat insurance fraud) statistically it just makes sense that Russians would end up seeing more meteors, and then be able to share the experience with the rest of the world!

This is exactly what happened early this morning, April 19 (local time), when a bright fireball flashed in the skies over Murmansk, located on the Kola Peninsula in northwest Russia near the border of Finland. Luckily not nearly as large or powerful as the Chelyabinsk meteor event from February 2013, no sound or air blast from this fireball has been reported and nobody was injured. Details on the object aren’t yet known… it could be a meteor (most likely) or it could be re-entering space debris. The video above, some of which was captured by Alexandr Nesterov from his dashcam, shows the object dramatically lighting up the early morning sky.

One Russian astronomer suggests this bolide may have been part of the debris that results in the Lyrid meteor shower, which peaks on April 22-23. (Source: NBC)

Source: RT.com

March 28, 2014May 25, 2023 by David Dickinson

Adventures in (Radio) Amateur Astronomy

Is there truly anything new under the Sun? Well, when it comes to amateur astronomy, many observers are branching out beyond the optical. And while it’s true that you can’t carry out infrared or X-ray astronomy from your backyard — or at least, not until amateurs begin launching their own space telescopes — you can join in the exciting world of amateur radio astronomy.

We’ll admit right out the gate that we’re a relative neophyte when it comes to the realm of radio astronomy. We have done radio observations of meteor showers in tandem with optical observations, and have delved into the trove of information on constructing radio telescopes over the years. Consider this post a primer of sorts, an intro into the world of radio amateur astronomy. If there’s enough interest, we’ll follow up with a multi-part saga, constructing and utilizing our own ad-hoc “redneck array” in our very own backyard with which to alarm the neighbors and probe the radio cosmos.

Repurposing a TV Dish for amatuater astronomy. Credit: NSF/NRAO/Assoc. Universities, Inc. — The “Itty-Bitty Array”- Re-purposing a TV Dish for amateur astronomy. Credit: NSF/NRAO/Assoc. Universities, Inc.

…And much like our exploits in planetary webcam imaging, we’ve discovered that you may have gear kicking around in the form of an old TV dish – remember satellite TV? – in your very own backyard. A simple radio telescope setup need not consist of anything more sophisticated than a dish (receiver), a signal strength detector (often standard for pointing a dish at a satellite during traditional installation) and a recorder. As you get into radio astronomy, you’ll want to include such essentials as mixers, oscillators, and amplifiers to boost your signal.

Frequency is the name of the game in amateur radio astronomy, and most scopes are geared towards the 18 megahertz to 10,000 megahertz range. A program known as Radio-SkyPipe makes a good graphic interface to turn your laptop into a recorder.

Radio astronomy was born in 1931, when Karl Jansky began researching the source of a faint background radio hiss with his dipole array while working for Bell Telephone. Jansky noticed the signal strength corresponded to the passage of the sidereal day, and correctly deduced that it was coming from the core of our Milky Way Galaxy located in the constellation Sagittarius. Just over a decade later, Australian radio astronomer Ruby Payne-Scott pioneered solar radio astronomy at the end of World War II, making the first ever observations of Type I and III solar bursts as well as conducting the first radio interferometry observations.

A replica of Jansky's first steerable antanta at Green Bank, West Virginia. — A replica of Jansky’s first steerable antenna at Green Bank, West Virginia. (Public Domain image)

What possible targets exist for the radio amateur astronomer? Well, just like those astronomers of yore, you’ll be able to detect the Sun, the Milky Way Galaxy, Geostationary and geosynchronous communication satellites and more. The simple dish system described above can also detect temperature changes on the surface of the Moon as it passes through its phases. Jupiter is also a fairly bright radio target for amateurs as well.

Radio meteors are also within the reach of your FM dial. If you’ve ever had your car radio on during a thunderstorm, you’ve probably heard the crackle across the radio spectrum caused by a nearby stroke of lightning. A directional antenna is preferred, but even a decent portable FM radio will pick up meteors on vacant bands outdoors. These are often heard as ‘pings’ or temporary reflections of distant radio stations off of the trail of ionized gas left in the wake of a meteor. Like with visual observing, radio meteors peak in activity towards local sunrise as the observer is being rotated forward into the Earth’s orbit.

Amateur SETI is also taking off, and no, we’re not talking about your crazy uncle who sits out at the end of runways watching for UFOs. BAMBI is a serious amateur-led project. Robert Gray chronicled his hunt for the elusive Wow! signal in his book by the same name, and continues an ad hoc SETI campaign. With increasingly more complex rigs and lots of time on their hands, it’s not out of the question that an amateur SETI detection could be achieved.

Another exciting possibility in radio astronomy is tracking satellites. HAM radio operators are able to listen in on the ISS on FM frequencies (click here for a list of uplink and downlink frequencies), and have even communicated with the ISS on occasion. AMSAT-UK maintains a great site that chronicles the world of amateur radio satellite tracking.

Amateur radio equipment that eventually made its way to to ISS aboard STS-106. (Credit: NASA).

Old TV dishes are being procured for professional use as well. One team in South Africa did just that back in 2011, scouring the continent for old defunct telecommunications dished to turn them into a low cost but effective radio array.

Several student projects exist out there as well. One fine example is NASA’s Radio JOVE project, which seeks student amateur radio observations of Jupiter and the Sun. A complete Radio Jove Kit, to include receiver and Radio-SkyPipe and Radio-Jupiter Pro software can be had for just under 300$ USD. You’d have a tough time putting together a high quality radio telescope for less than that! And that’s just in time for prime Jupiter observing as the giant planet approaches quadrature on April 1^st (no fooling, we swear) and is favorably placed for evening observing, both radio and optical.

Fearing what the local homeowner’s association will say when you deploy your very own version of Jodrell Bank in your backyard? There are several online radio astronomy projects to engage in as well. SETI@Home is the original crowd sourced search for ET online. The Zooniverse now hosts Radio Galaxy Zoo, hunting for erupting black holes in data provided by the Karl Jansky Very Large Array and the Australia Telescope Compact Array. PULSE@Parkes is another exciting student opportunity that lets users control an actual professional telescope. Or you can just listen for meteor pings online via NASA’s forward scatter meteor radar based out of the Marshall Space Flight Center in Huntsville, Alabama. Adrian West also hosts live radio meteor tracking on his outstanding Meteorwatch website during times of peak activity.

Forward Scatter — A diagram of a basic forward scatter radar system for meteor observing. Credit: NASA

Interested? Other possibilities exist for the advanced user, including monitoring radio aurorae, interferometry, catching the hiss of the cosmic microwave background and even receiving signals from more distant spacecraft, such as China’s Yutu rover on the Moon.

Think of this post as a primer to the exciting world of amateur radio astronomy. If there’s enough interest, we’ll do a follow up “how-to” article as we assemble and operate a functional amateur radio telescope. Or perhaps you’re an accomplished amateur radio astronomer, with some tips and tricks to share. There’s more to the universe than meets the eye!

-Also be sure to check out SARA, the Society of Amateur Radio Astronomers.

March 27, 2014December 23, 2015 by Bob King

Mars-Bound Comet Siding Spring Sprouts Multiple Jets

Hubble Space Telescope picture of comet C/2013 A1 Siding Spring as observed on March 11, 2014. At that time the comet was 353 million miles from Earth. When the glow of the coma is subtracted through image processing, which incorporates a smooth model of the coma's light distribution, Hubble resolves what appear to be two jets of dust coming off the nucleus in opposite directions. This means that only portions of the surface of the nucleus are presently active as they are warmed by sunlight, say researchers. Credit: NASA, ESA, and J.-Y. Li (Planetary Science Institute)

Comet Siding Spring, on its way to a close brush with Mars on October 19, has been kicking up a storm lately. New images from Hubble Space Telescope taken on March 11, when the comet was just this side of Jupiter, reveal multiple jets of gas and dust.

Illustration showing Comet Siding Spring's orbit and close pass of Mars as it swings around the sun this year. Credit: NASA — Illustration showing Comet Siding Spring’s orbit and close pass of Mars as it plies its way through the inner solar system this year. Credit: NASA

Discovered in January 2013 by Robert H. McNaught at Siding Spring Observatory in Australia, the comet is falling toward the sun along a roughly 1 million year orbit. It will gradually brighten through spring and summer until reaching binocular brightness this fall when it passes 130 million miles (209 million km) from Earth.

Views of the comet on three different dates. Top shows a series of unfiltered images while the bottom are filtered to better show the jets. Credit: — Views of the comet on three different dates. Top shows a series of unfiltered images while the bottom are filtered to better show the jets. Comet Siding Spring’s hazy coma measures about 12,000 miles across and it’s presently about 353 million miles (568 million km) from the sun. Credit: NASA, ESA, J.-Y. Li (Planetary Science Institute)

Astronomers were particularly interested in getting images when Earth crossed the comet’s orbital plane, the path the comet takes as it orbits the sun. The positioning of the two bodies allowed Hubble to make crucial observations of how fast dust particles streamed off the nucleus.

Comet C/2013 A1 Siding Spring photographed from Australia on March 4, 2014. Credit: Rolando Ligustri

“This is critical information that we need to determine whether, and to what degree, dust grains in the coma of the comet will impact Mars and spacecraft in the vicinity of Mars,” said Jian-Yang Li of the Planetary Science Institute in Tucson, Arizona.

On October 19 this year, Comet Siding Spring will pass within 84,000 miles (135,000 km) of Mars or less than half the distance of our moon. There’s a distinct possibility that orbiting Mars probes like NASA’s Mars Reconnaissance Orbiter and the European Mars Express might be enveloped by the comet’s coma (hazy atmosphere) and pelted by dust.

Mars and Comet C/2013 A1 Siding Spring will overlap as seen from Earth on Oct. 19, 2014 when the comet might pass as close as 25,700 miles (41,300 km) from the planet’s center. View shows the sky at the end of evening twilight facing southwest. Stellarium

While comet dust particles are only 1 to 1/10,000 of a centimeter wide, they’ll be moving at 124,000 mph (200,000 km/hr). At that speed even dust motes small can be destructive. Plans are being considered to alter the orbits of the spacecraft to evade the worst of the potential blast. On the bright side, the Red Planet may witness a spectacular meteor storm! Protected by the atmosphere, the Martian rovers aren’t expected to be affected.

I know where I’ll be on October 19 – in the front yard peering at Mars through my telescope. Even if the comet doesn’t affect the planet, seeing the two overlap in conjunction will be a sight not to miss.

February 24, 2014December 23, 2015 by Elizabeth Howell

Chelyabinsk ‘Was A Pretty Nasty Event’ And Is Spurring Asteroid Action

Chelyabinsk fireball recorded by a dashcam from Kamensk-Uralsky north of Chelyabinsk where it was still dawn. A study of the area near this meteor air burst revealed similar signatures to the Tall el_Hammam site.

Looking at the power of the Chelyabinsk meteor (which struck a year ago and is visible starting around 1:15 in the video above) is still terrifying all these months later. Happily for those of on Earth worried about these big space rocks, the world’s space agencies are taking the threat seriously and are starting to implement new tracking systems to look out for more threatening space rocks.

“It was a pretty nasty event. Luckily, no one was killed but it just shows the sort of force that these things have,” said Alan Harris, senior scientist of the DLR Institute of Planetary Research in Berlin, in this new European Space Agency video.

An asteroid that is only about 100 meters (328 feet) in diameter, for example, “could actually completely destroy an urban area in the worst case. So those are the things we’re really looking out for and trying to find ways to tackle.”

Check out the video for some examples of how the Europeans are talking about dealing with this problem, including a fun comparison to cosmic billiards and a more serious discussion on how to shove these rocks aside if they were on a collision course with our planet.

For more information on tracking down killer asteroids, check out this past video with Universe Today founder Fraser Cain.

February 15, 2014April 26, 2016 by Bob King

Happy 1st Anniversary Chelyabinsk! The Fireball that Woke Up the World

Wonder and terror. Every time I watch the dashcam videos of the Chelyabinsk fireball it sends chills down my spine. One year ago today, February 15, 2013, the good citizens of Chelyabinsk, Russia and surrounding towns collectively experienced these two powerful emotions as they witnessed the largest meteorite fall in over 100 years.

Incredible compilation of dashcam and security camera videos of the fireball

The Chelyabinsk fall, the largest witnessed meteorite fall since the Tunguska event in 1908, exploded with 20-30 times the force of the atomic bomb over Hiroshima at an altitude of just 14.5 miles (23 km). Before it detonated into thousands of mostly gravel-sized meteorites and dust, it’s estimate the incoming meteoroid was some 66 feet (20-meters) end to end, as tall as a five-story building. The shock wave from the explosion shattered windows up and down the city, injuring nearly 1,500 people.

Friction and enormous pressures placed upon the Chelyabinsk meteoroid by the atmosphere caused it to explode to pieces and send a shock wave across the cities below. This is a selection of typical small, fusion-crust covered Chelyabinsk meteorites. The U.S. penny is 9mm in diameter. Credit: Bob King — Atmospheric friction pressure on the Chelyabinsk meteoroid caused it to explode to pieces and send a shock wave across the land below. Pictured is a selection of typical small, fusion-crust covered Chelyabinsk meteorites recovered shortly after the fall. The U.S. penny is 9mm in diameter. Credit: Bob King

For nearby observers it briefly appeared brighter than the sun. NASA Meteorite researcher Peter Jenniskens conducted an Internet survey of eyewitnesses and found that eye pain and temporary blindness were the most common complaints from those who looked directly at the fireball. 20 people also reported sunburns including one person burned so badly that his skin peeled:

Trajectory projection and strewnfield map showing the main fireball (and two additional explosions) at top and the elliptical shaped area where the densest concentration of meteorites were found. Credit: Svend Buhl and K. Wimmer — Map showing the trajectory of the main fireball in yellow (and two additional explosions at top left). The pink oval, called the strewnfield, is where the densest concentration of meteorites were found. Click to see additional maps. Credit: Svend Buhl and K. Wimmer

“We calculated how much UV light came down and we think it’s possible,” Jenniskens said. Perhaps surprisingly, most of the meteoroid’s mass – an estimated 76% – burned up and was converted to dust during atmospheric entry. It’s estimated that only 0.05% of the original meteoroid or 9,000 to 13,000 pounds of meteorites fell to the ground.

No video I’ve seen better captures the both the explosion of the fireball and ensuring confusion and chaos better than this one.

The largest fragment, weighing 1,442 lbs. (654 kg), punched a hole in the ice of Lake Chebarkul. Divers raised it from the bottom muck on Oct. 16 last year and rafted it ashore, where scientists and excited onlookers watched as the massive space rock was hoisted onto a scale and promptly broke into three pieces. Moments later the scale itself broke from the weight.

The 26-foot-wide (8-meter) hole punched in the ice of Chebarkul Lake by the largest fragment of the Chelyabinsk meteorite. Credit: Eduard Kalinin

There were plenty of meteorite to go around as local residents tracked down thousands of fragments by looking for holes pierced in the snow cover by the hail of space rocks. Working with hands and trowels, they dug out mostly small, rounded rocks covered in fresh black fusion crust, a 1-2 mm thick layer of rock blackened and melted rock from frictional heating by the atmosphere. According to the Meteoritical Bulletin Database entry, the total mass of the recovered meteorites to date comes to 1,000 kg (2,204 lbs.) with locals finding up to more than half of that total.

Animation of the orbit Chelyabinsk meteoroid via Ferrin and Zuluaga. Meteoroid is the name given a meteor while still orbiting the sun before it enters Earth’s atmosphere.

Thanks to the unprecedented number of observations of the fireball recorded by dashcams, security cameras and eyewitness accounts, astronomers were able to determine an orbit for Although some uncertainties remain, the object is (was) a member of the Apollo family of asteroids, named for 1862 Apollo, discovered in 1932. Apollos cross Earth’s orbit on a routine basis when they’re nearest the sun. Chelyabink’s most recent crossing was of course its last.

Chelyabinsk meteorites exhibit many signs of shock created during an asteroid impact long ago. Many specimens show a typical pale white color with small chondrules typical of LL5 chondrite. A closer look shows fine, dark shock veins of melted glass. Other fragments are made of impact melt, rock shocked-heated and blackened by impact. Credit: Bob King — Chelyabinsk meteorites tell the tale of an earlier impact with another asteroid 4.452 billion years ago. Many specimens are pale white with small chondrules typical of LL5 chondrites. A closer look shows fine, dark shock veins of melted glass. Other fragments are made of pure impact melt, rock shocked-heated, melted and blackened by impact. Credit: Bob King

Chelyabinsk belongs to a class of meteorites called ordinary chondrites, a broad category that includes most stony meteorite types. The chondrites formed from dust and metals whirling about the newborn sun some 4.5 billion years ago; they later served as the building blocks for the planets, asteroids and comets that populate our solar system. Chondrites are further subdivided into many categories. Chelyabinsk belongs to the scarce LL5 class — a low iron, low metal stony meteorite composed of silicate materials like olivine and plagioclase along with small amounts of iron-nickel metal.

Most of the Chelyabinsk meteorites were shattered and broken during the explosion / shock blast, revealing brecciation, metal and shock veins in their interiors. Credit: Bob King

A thin slice of Chelyabinsk impact melt breccia. Flows of once-molten rock (gray) surround islands of less altered material. A small iron nickel nodule is seen at lower left. Credit: Bob King — A thin slice of Chelyabinsk impact melt breccia. Flows of once-molten rock (paler gray) surround islands of less altered material. A small iron nickel nodule is seen at lower left. Credit: Bob King

A closer look at Chelyabinsk meteorites reveals a fascinating story of ancient impact. Remarkably, the seeds of the meteoroid’s atmospheric destruction were sown 115 million years after the solar system’s formation when ur-Chelyabinsk was struck by another asteroid, suffering a powerful shock event that heated, fragmented and partially melted its interior. Look inside a specimen and the signs are everywhere – flows of melted rock, spider webby shock veins of melted silicates and peculiar, shiny cleavages called “slickensides” where meteorites broke along pre-existing fracture planes.

Slickensides on a Chelyabinsk meteorite fragment where the fragment broke along a pre-existing fracture plane. Credit: Bob King

Jenniskens calculated that the object may have come from the Flora family of S-type or stony asteroids in the belt between Mars and Jupiter. Somehow Chelyabinsk held together after the impact until nearly the time it met its fate with Earth’s atmosphere. Researchers at University of Tokyo and Waseda University in Japan discovered that the meteorite had only been exposed to cosmic rays for an unusually brief time for a Flora member – just 1.2 million years. Typical exposures are much longer and indicate that the Chelyabinsk parent asteroid only recently broke apart. Jenniskens speculates it was likely part of a loosely-bound, rubble pile asteroid that may have broken apart during a previous close encounter with Earth in the last 1.2 million years. The rest of the rubble pile might still be orbiting relatively nearby as part of the larger population of near-Earth asteroids.

Rivulets of melted rock line the fusion crust of melted rock on this small Chelyabinsk meteorite. Credit: Bob King

Good thing Chelyabinsk arrived pre-fractured. Had it been solid through and through, more of the original asteroid might have survived its fiery descent and wreaked even more havoc in in its wake.

We’re fortunate that Chelyabinsk contains a fantastic diversity of features and that we have so many pieces for study. Surveys have found some 500 near-Earth asteroids. No doubt some are part of the parent body of Chelyabinsk and may grace our skies on some future date. Whatever happens, Feb. 15, 2013 will go down as a very loud “wake-up call” for our species to implement more asteroid-hunting programs both in space and on the ground. Enjoy a few more photos of this incredible gift from space: