Astronomy

5 sec flare near Arcturus

5 sec flare near Arcturus


We are searching data for your request:

Forums and discussions:
Manuals and reference books:
Data from registers:
Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.

Hello fellow amateur and professional astronomers,

On July July 17, 2017, I was at an observing session in Avrig, Sibiu county, Romania (45.7288° N, 24.3784° E). At approx 11:30 pm I pointed my green laser pointer (class III, wavelength 532 nm +/-10, YL-Laser 303) towards Arcturus in order to help my colleague align the SW AZEQ 5 mount within the 3-star procedure.

While the laser beam was on, at approx 1 arcminute beneath and to the left from Arcturus, with my naked eye, I observed a point of light (white/blueish) lighting up to the point which I estimate to be close to the visual magnitude of Jupiter or slightly higher for appprox 5 seconds, and then the "flare" faded out to black. As there was no "regular" star-like remanant, I was left to conclude that the initial flare did not originate from a star.

I ruled out a reflection of the laser beam from a satelite (as too far for my laser's power), a plane or a bird (due to the white/blueish light I saw, its fixed position and apparent distance to my eye), as well the possibility of a meteorite burst (as it had no apparent trajectory, but it appeared as a fixed point).

I am so intrigued and curious as to what possible optics or physics could have been involved and explanations or ideas you may have to explain the phenomenon?

I searched online for others' possible similar observations without success.


My first thought is that you saw a flare from a satellite, meaning a favorable reflection off of a solar panel or something. I use the software "Heavensat", and it shows the satellite Nextsat (Norad number 30774) passed very close to Arcturus at 23:40 pm from your location (45.7288° N, 24.3784° E). Note that I am assuming that your time is 3 hours ahead of UT (Universal Time).

I do not know if Nextsat typically flares, although reflections from satellites are common. Nextsat is in a low altitude orbit, so its motion would normally be detectible. Perhaps the duration of the brightening was shorter than you estimate (so that the motion was not detectible), or it was so unexpected that you did not notice the motion.

My second thought would be a head on meteor like you suggested.


Tonight’s Sky

Tonight, find the Hunting Dogs. The chart above looks directly overhead at nightfall or early evening in May, as seen from a mid-latitude in the Northern Hemisphere. It’s as if we’re viewing the sky from the comfort of a reclining lawn chair, with our feet pointing southward. The constellation Leo the Lion stands high in the southern sky, while the upside-down Big Dipper is high in the north. Notice the Big Dipper and Leo. You can use them to star-hop to to the constellation Canes Venatici, the Hunting Dogs.

Many people know how to find Polaris, the North Star, by drawing a line through the Big Dipper pointer stars, Dubhe and Merak. You can also find Leo by drawing a line through these same pointer stars, but in the opposite direction.

Extend a line from the star Alkaid in the Big Dipper to the star Denebola in Leo. One-third the way along this line, you’ll see Cor Caroli, Canes Venatici’s brightest star. A telescope reveals that Cor Caroli is a binary star: two stars orbiting a common center of mass.

The two component stars are an estimated 675 astronomical units (AU) apart with an orbital period of around 8,300 years. Given this information, astronomers can figure out the combined mass of Cor Caroli in solar masses with this equation: mass = a 3 /p 2 , whereby a = semi-major axis (mean distance) = 675 AU, and p = orbital period = 8,300 years. If you do the calculations, you’ll find that Cor Caroli has about 4.46 times the mass of our sun.

By the way, Cor Caroli (Latin for “Heart of Charles”) is named in honor of England’s King Charles I, who had his head cut off in 1649. The name first appeared on English star maps in the late 1600s as Cor Caroli Regis Martyris (“Heart of Charles the Martyr King”). King Charles II, the son of King Charles I, founded the Royal Observatory in Greenwich, England, in 1675.

If you’re familiar with the constellation Leo the Lion, you can star-hop to Cor Caroli by drawing an imaginary line from the star Alkaid of the Big Dipper to the Leo star Denebola. Image via Wikimedia Commons.

Bottom line: Star-hop to Canes Venatici, the Hunting Dogs, tonight! You can do it, if you can find the constellation Leo the Lion and the famous Big Dipper asterism.


Star Facts: Arcturus

Arcturus by Mike Hankey [www.mikesastrophotos.com]

Arcturus is an orange giant star located 37 light years away in the Boötes constellation, with its apparent magnitude of -0.05 making it the 4th brightest star in the night sky. Its name, meaning “Guardian of the Bear”, was a reference to the fact that since Arcturus was the most luminous star in Boötes the Herdsman , it was only reasonable to the ancient Greeks to see it as the “guardian” of both Ursa Major and Ursa Minor, both of which are nearby constellations.

Quick Facts

• Coordinates: RA 14h 15m 39.7s| Dec +19° 10′ 57″
• Star Type: Orange Giant – K Class (K1.5IIIFe-0.5)
• Constellation: Boötes
• Distance to Earth: 37 light years
• Apparent Magnitude: -0.05
• Luminosity: 170 times solar luminosity
• Surface Temp: 4,000C (7,200F)
• Mass: 1.10 solar masses
• Radius: 11 million miles (25.7 solar radii)
• Rotational Velocity: 2.4 km per second
• Age: 10 billion years old
• Designations: Arcturus, Alpha Boötis, Alramech, Abramech

Look for Arcturus by following an imaginary arc line from the Big Dipper’s handle until you see the huge bright, orange star in Bootes. Located just 19 degrees north of the celestial equator, it is therefore visible from both the northern and southern hemispheres most of the year round at some part of the night. In the northern hemisphere, Arcturus is associated with the arrival of spring , and in the southern hemisphere heralds the start of autumn.

Arcturus has a visual magnitude of -0.05, making it is the brightest star north of the celestial equator, and the 4th most luminous star in the entire sky. Although Alpha Centauri is brighter than Arcturus, it is only as a result of the combined magnitudes of the Alpha Centauri system, whose individual components are all dimmer to the unaided eye than Arcturus. This fact makes Arcturus the third most luminous solitary star in the entire sky, with Alpha Centauri A following close behind with a visual magnitude of -0.01.

Arcturus is thought to have formed outside of the plane of the Milky Way, in the outer reaches of the galaxy’s thick halo. Some investigators have also posited that Arcturus may actually have been formed in a satellite galaxy that has since been devoured by the Milky Way, and that the 52 stars that share its motion and trajectory through the Milky Way, are in fact the remnants of that galaxy.

Physical Properties

Arcturus is at least 110 times as bright as the Sun, although, much of its light is radiated in infrared wavelengths. If the total energy production of Arcturus is taken into account, the star is about 180 times as energetic as the Sun, with the apparent discrepancy explained by its cooler surface temperature of 4,286 K making it less efficient at producing energy than our Sun (5,778 K) at any given volume.

Arcturus is believed to have only about 1.8 or so solar masses, despite being about 26 times as big as the Sun, and has an estimated age range of between 6 billion and 8.5 billion years. This makes the star old enough to have begun converting helium into oxygen and carbon, and if this is indeed the case, it will continue to expand until it has converted all of its helium supply. It will subsequently blow off its outer layers, and evolve into a white dwarf surrounded by a planetary nebula.

Proper Motion

One notable feature of Arcturus is its high proper motion, which at a break-neck speed of 122 kilometres per second (2 seconds of arc per year), is the fastest of any first-magnitude star except Alpha Centauri. In the case of Arcturus, however, it is not moving in the broad plane of the Milky Way, but almost perpendicularly to the galaxy’s plane, much like a stone dropped into a pool of water. Arcturus is, however, not alone in its headlong plunge through the Milky Way – it is accompanied by 52 other stars, which are collectively known as the Arcturus Stream.

Arcturus in History

The ancient Greeks saw Arcturus in Bootes as the guardian of both Ursa Major and Ursa Minor, while in ancient Rome it was seen as the harbinger of stormy, if not tempestuous weather. Arcturus is one of only a few stars mentioned in the Bible, and by the Middle Ages it was assigned magical properties and lumped together with fourteen other stars which were collectively known as “Behenian fixed stars”, considered especially useful in medieval astrology.

In Australia, the Wotjobaluk Koori aborigines called Arcturus “Marpean-kurrk”, the mother of Djuit (Antares), and Weet-kurrk (Muphrid). The arrival of Arcturus in the north coincided with the arrival of wood-ant larvae, which formed a part of the diet of the Aborigines in south-eastern Australia. Arcturus also marked the beginning of summer when it set in the west with the Sun, which event also marked the disappearance of the wood-ant larvae.


The Ten Brightest Stars (and where they are, with video) – 1. Arcturus

Since then, this article has been one of our most popular and, accordingly, we’re going to continue the discussion, expanding the list from 5 (6, really, when you consider the sun) to ten. Since the list is more expansive and in the interests of keeping the articles down to a 3-5 minute read, we’re going to depart from the original format of presenting all the stars within a single article and publish a new article for each of the 10 brightest stars.

This article will be the first in a ten-part series, each published over a period of ten weeks with Arcturus the first bright star of the series. Additionally, each of the ten articles will have a corresponding video, published on our YouTube Channel. This installment’s video is linked at the foot of the page.

Going out to look up at the stars on a clear, dark night can be daunting, if not for its beauty and majesty but for what may seem like an uncountable number of stars you often hear the comment “there are millions” of stars”! Indeed, there are quite a few more than mere “millions” there are approximately 10 22 (1 followed by 22 zeros) stars in the universe! Of those how many can we mere mortals see on a given night? Of those 1022 stars, there are about 250 billion in our Milky Way galaxy and of those, about half are forever invisible from earth, being located on the other side of the galaxy. The question then becomes, of those 125 billion or so stars accessible by observes on Earth, how many can we see with the smallest and simplest of optical instruments at our disposal, our eyes?

Decades ago, Yale University Astronomer Dorrit Hoffleit compiled the Yale Bright Star Catalog. It includes every star visible from Earth to magnitude 6.5, the naked eye limit for most of humanity. This limit is determined by the maximum size the eye’s pupil can dilate, about 0.5 cm on average (a bit smaller than a ¼ inch) that’s why astronomers keep building larger and larger telescopes since the greater the telescope’s diameter (aperture), the more light is collected and thus, the fainter we can see. Dr. Hoffleit determined that there are 9,096 stars over the entire sky, between the Northern and Southern hemispheres, within the 6.5 magnitude, human-eye limit.

Any article that discusses this topic would be incomplete if it did not pay tribute to Dr. Hoffleit. She remained active in her life-long love and pursuit of chronicling and studying the stars, beyond her 100-th birthday on March 9, 2007, within weeks of her death from from cancer.

Dorrit Hoffleit, who continued astronomical studies for decades after her official retirement, celebrated her 100th birthday on March 9, 2007. Image credit: Kelly Beatty, Sky and Telescope

Arcturus

We’ve published two articles about this star in as many years and this article will be more than just a compilation of those articles.

Some Thoughts about Summer, Arcturus and the Future

Reflections on Arcturus, The Sun and the Changing Seasons

A common theme that runs through these articles is change, how close we are metaphorically, here, on earth with our sun and solar system, to Arcturus, and how distant we are at the same time. We’re separated in time from Arcturus by 2.5 Billion years and in space by 40 light years Arcturus is 40 Light years distant (the light we see from Arcturus, shimmering warm and bright in our summer evening sky tonight, left the star 40 years ago).

To study Arcturus is to study ourselves and the long-term evolution of our own star and how it will effect our solar system over the intervening 2.5 billion years between now and when our sun will have evolved to become a red giant star, an evolved star identical in every aspect to how Arcturus is today! Arcturus is 1 solar mass: it’s the same mass as the sun but 2.5 billion years older, or 7.1 billion years old! The one aspect of any star that principally effects its evolution is its mass. The mass of a star determines its lifespan, its luminosity, temperature and evolution from a nascent proto-star to its ultimate end-state. In the case of Arcturus and our sun, that end-state will be a white dwarf star.

Arcturus is the brightest star in Bootes, the herdsman, high in the northwest after twilight during late July and into August it is also the brightest star in the Northern Hemisphere after Vega.

Arcturus, as depicted in this late September view of the western sky with an actual image of the star, illustrating its warm red light, superimposed atop the artifical star produced in Stellarium. Image credit: the Author and Stellarium

View of Arcturus tonight, high in the northwest at twilight.

This current view of Arcturus, high in the northwest at twilight tonight, provides a signpost to its host constellation, Bootes, and other notable objects and constellations such as the first quarter moon to the east of Spica, the brightest star in Virgo. A catchy phrase that helps one navigate this part of the sky is: follow the arc to Arcturus and speed to Spica: the [arc] of the Big Dipper’s handle.

A new feature of our home page, an interactive Sky Tonight portal, via Stellarium, would be the perfect companion along with a pair of binoculars, to view beautiful Arcturus and the surrounding Northwest sky.

To close out this installment of “The Ten Brightest Stars“, we’d like to share an image of a stunning globular cluster acquired by Dr. James Daly, a frequent author and contributor at Astronomy for Change. What is particularly significant about this object within the context of this discussion of Arcturus, the brightest stars visible in this image (and in the cluster) are red giant stars, stars just like Arcturus! Globular clusters contain some of the oldest stars in the universe, stars similar in age to Arcturus and many just like it.

Known as Messier-3 (M-3 for short), the cluster is the third object in the list of non-cometary objects known as the the Messier Catalog, named in honor of the 18th century French astronomer, Charles Messier. The cluster is 34,000 light years distant (when you observe this object, the light striking your eyes has been traveling for 34,000 years, a time that predates the end of the last ice age (11,500 yrs ago) by 22,500 years! Even more remarkable and something that really gives you a sense of size, scale and time, these brightest stars in M-3 are at the threshold of visibility for a moderately large amateur telescope at magnitude 12.5 and fainter recall, we previously discussed magnitude above. Arcturus, beckoning warm and bright in our evening sky like a brilliant red sapphire, would now be at the threshold of visibility! This very star, so warm and inviting in our evening sky at 40 light years, now requires a substantial telescope to be seen at all at 34,000 light years!

The globular cluster, Messier-3, as imaged by Dr. James Daly. The tiny points of light that you see, the brightest stars in the cluster, are stars just like Arcturus! Image credit: James Daly, Ph.D. Image acquired with a 20 cm reflecting telescope.

Although you will need a telescope to resolve any of the stars in this cluster, M-3 is easily observed with a good pair of binoculars. To locate it, launch the Sky Tonight portal available on our home page.

Featured image: comparison of the sun to Arcturus (an evolved, one solar-mass star) and Antares, a high-mass red giant that will soon end its life in spectacular fashion as a Type-II Supernova.

Imagination is more important than knowledge

An index of all articles can be found here.

If you enjoyed this article, please consider supporting us with a modest donation

or through a subscription on our Patreon Page
Membership at Astronomy for Change is Free!


Main menu

Posted by Steve Holmes2 at 13:48 on 2013 Jun 13

I was preparing to observe (by eye) a pass of the ATV-4 on the night of Tuesday 11th June. Arcturus, near to which the ATV was to pass, was very bright in the south so I was keeping an eye on that general area in case I missed the ATV on the rising part of its pass. Suddenly, "another Arcturus" appeared slightly above it and somewhat to its left and began to move slowly from left to right. I was sure this could not have been the ATV so I moved my gaze to where it should then be, and picked it up immediately. I then looked back towards Arcturus, to find that the mystery object was no longer visible.I was absolutely convinced that the object was not an aircraft or a helicopter (both of which are frequently seen in our area) nor something like a "hot-air lantern" so I consulted the Heavens-Above website to find that the Terra earth-observation satellite was passing at the exact time (22:56 BST) and place when I had seen the mystery object (as had my wife, so I wasn't imagining it!). Its quoted magnitude was only 2.0 though, so it would not have been easily visible, and definitely not as bright as Arcturus (mag 0.0). I thus presumed I had seen a "flare" from the large solar array panel carried by Terra (in the same way flares are produced by the Iridium satellites).This is all rather conjectural though, so I wondered whether anyone else happened to have also seen this event? The geographical area where a flare is visible is rather restricted so it would probably need to be another observer in north Suffolk (I'm at 52.30deg N, 1.37deg E).Any observations or comments?Steve Holmes

Posted by Peter Meadows at 21:43 on 2013 Jun 13

Steve,Here is an image of another Earth Observation satellite, Envisat, which shows flaring. The image was taken last August (5th at 21:16 UT). The Summer Triangle comprising Deneb (top left of image), Vega (middle) and Altair (bottom left) and some high thin cloud are also shown. Peter

Posted by Steve Holmes2 at 01:09 on 2013 Jun 14

This image has a number of interesting aspects:-1) The track of Envisat across the sky as shown by the stars you mention is pretty-well parallel to that of Terra as shown on Heavens-Above. This confirms that the actual orbit of Envisat is polar, as for Terra, which is quite usual for an earth-observation satellite.2) The brighness profile of the flare is totally different from that of an Iridium flare or of the one I saw. This one seems rather more of a "flash" than a flare: Iridium flares tend to build up and die down fairly steadily over a period of about 30sec. The occasional one has a very bright central portion (when you're close to the "centre line") but still has the steady build up and down. The Envisat "base level" is much less bright than for an Iridium flare.3) The Envisat image shows a number of subsidiary flares to the lower left of the main "flash". These are presumably caused by different parts of the satellite catching the sun before the main solar array, which doesn't happen with Iridium flares.For comparison, here's a couple of shots of Iridium flares. The first one has an unusually bright centre section (actually mag -8 or brighter!) and the second is a quite rare double flare - it's a single exposure of 30secs, capturing two adjacent flares just 6 sec apart.Bizarrely, while I was composing this reply I popped outside to see whether the sky was clearing and, purely by chance, saw a flare low down in the west! This was not listed as an Iridium flare by Heavens-Above but IGS 1A was passing that exact spot at the right time so I assume that's what it was. The IGS family is known to flare, which raises the possibility that the "event" I saw on 11th June was caused by IGS 5A rather than Terra: it had almost exactly the same track but was close to Arcturus 1min earlier (which is within the tolerance of my "quick look at my watch in the dark" timings).Further comments invited.Steve Holmes


CNYO Observing Log: Beaver Lake Nature Center, 18 September 2014

Greetings fellow astrophiles,

After a double wash-out for our scheduled August 8/15 event, CNYO made a triumphant return to Beaver Lake Nature Center for one last end-of-Summer public viewing session. While the local meteorologists and the Clear Sky Clock predicting clear, dark skies for the entire evening, the observing itself was still a bit touch-and-go until about 9:00 p.m., when the whole sky finally opened up.

Despite a small snafu with the Beaver Lake events calendar (or, specifically, our lack of presence on it for this rescheduled event), we still managed 10 attendees (and passed the word along to several people there for an event earlier in the evening – I’m also happy to report that Patricia’s attendance justified our meetup group event scheduling!). With four CNYO’ers (Bob Piekiel, Larry Slosberg, Christopher Schuck, and myself) and three scopes present (including Bob Piekiel’s Celestron NexStar 11, Larry Slosberg’s 12” New Moon Telescope Dob, and my 12.5” NMT Dob) this was a great chance for several of the new observers to ask all kinds of questions, learn all the mechanics of observing through someone else’s scope, and, of course, take in some great sights at their own pace.

The 7:00 p.m. setup started promising, with otherwise overcast conditions gradually giving way to clearings to the Northwest. That all changed for the worse around 8:00 p.m. (when everyone showed up), when those same NW skies closed right up again, gradually devouring Arcturus, Vega, and any other brighter stars one might align with. The next hour was goodness-challenged, giving us plenty of time to host a Q+A, show the scope workings, remark on the amount of reflected light from Syracuse, and swing right around to objects within the few sucker holes that opened. And when all looked lost (or unobservable), the 9:00 p.m. sky finally cleared right up to a near-perfect late Summer sky, complete with a noticeable Milky Way band, bright Summer Triangle, and a host of satellites, random meteors, and bright Summer Messiers.

As has been the case for nearly every public viewing session this year, all the new eyes were treated to some of the best the Summer and Fall have to offer. These include:

M13 – The bright globular (“globe” not “glob”) cluster in Hercules
M31/32 – The Andromeda Galaxy (and its brighter, more separated satellite M32)
M57 – The Ring Nebula in Lyra
Herschel’s Garnet Star – To show very clearly that many stars have identifiable colors when magnified
Albireo – To reinforce the color argument above and to show one of the prominent doubles in the Night Sky, right at the tip of Cygnus.
Alcor/Mizar – Did you know that Alcor/Mizar is actually a sextuple star system? Alcor is its own double, each in Mizar is a double, and recent data reveals that the Alcor pair is gravitationally bound to the Mizar quartet.

To the observing list was added a discussion of how to begin learning the constellations. As we’ve discussed at several sessions, the best place to start is due North, committing the circumpolar constellations to memory FIRST. For those unfamiliar, these are the six constellations that never set below the horizon from our latitude (Ursa Minor (Little Dipper), most or Ursa Major (Big Dipper), Cassiopeia, Cepheus, Draco, and Camelopardalis (and if you can find Camelopardalis, you’re ready for anything). We’ve even consolidated all of this material into one of our introductory brochures for your downloading and printing pleasure:


Contents

The time and place of the satellite's flare can be predicted only when the satellite is controlled, and its orientation in space is known. In this case it is possible to predict the exact time of the flare, its place in the sky, the brightness and duration.

Iridium flares Edit

The first generation of the Iridium constellation launched a total of 95 telecommunication satellites in low Earth orbit which were known to cause Iridium flares, the brightest flares of all orbiting satellites, starting in 1997. From 2017 to 2019 they were replaced with a new generation that does not produce flares, with the first generation completely deorbited by 27 December 2019. [16]

While the first-generation Iridium satellites were still controlled, their flares could be predicted. [17] These Iridium communication satellites had three polished door-sized antennas, 120° apart and at 40° angles with the main bus. The forward antenna faced the direction the satellite is traveling. Occasionally, an antenna reflects sunlight directly down at Earth, creating a predictable and quickly moving illuminated spot on the surface below of about 10 km (6 mi) diameter. To an observer this looks like a bright flash, or flare in the sky, with a duration of a few seconds.

Ranging up to −9.5 magnitude, some of the flares were so bright that they could be seen in the daytime. This flashing caused some annoyance to astronomers, as the flares occasionally disturbed observations. [18]

As the Iridium constellation consisted of 66 working satellites, Iridium flares were visible quite often (2 to 4 times per night). Flares of brightness −5 magnitude occurred 3 to 4 times per week, and −8 magnitude were visible 3 to 5 times per month for stationary observers.

Flares could also occur from solar panels, but they were not as bright (up to −3.5 magnitude). Such flares lasted about twice as long as those from the main mission antennas (MMA), because the so-called "mirror angle" for the solar panels was twice that for the MMAs. There were also rare cases of flares from MMAs and solar panels, or two MMAs (front and either right or left) of one satellite in a single pass.

The flares were bright enough to be seen at night in big cities where light pollution usually prevents most stellar observation. When not flaring, the satellites were often visible crossing the night sky at a typical magnitude of 6, similar to a dim star.

From 2017 to 2019, a new generation of Iridium satellites was deployed which does not exhibit the characteristic flares. As the first generation were replaced and retired, flares became less frequent. The last of the first-generation satellites was deorbited on 27 December 2019, ending predictable Iridium flares. [19] [16]


Wikipedia:Vital articles/Level/5/Physical sciences/Astronomy

Vital articles is a list of subjects for which Wikipedia should have corresponding high-quality articles. It serves as a centralized watchlist to track the status of Wikipedia's most essential articles. This is one of the sub-lists of the fifty thousand article Vital articles/Level 5 and is currently under construction.

  • Former featured articles
  • A-class articles
  • Delisted good articles
  • B-class articles
  • C-class articles
  • Start-class articles
  • Stub-class articles
  • List-class articles
  • Unassessed
  • A full list is at Template:Icon/doc

These symbols and article counts are updated daily by User:cewbot.

  • The bot only update counter with the pattern "(000 articles)" in section title.
  • All attributes of articles get from corresponding categories.
  • The bot will automatically update the summary table if there are summary table marks. Please refer to Wikipedia:Vital articles for the example of summary table.

Not sure what I saw. Three bright flashes, maybe a minute apart each.

Hi, so I’m actually fairly knowledgeable as far as amateurs go when it comes to astronomy but this one has stumped me.

I’m out camping in Utah about an hour or so drive north of Salt Lake City and sleeping under the stars.

While looking for satellites I saw what I initially thought was an iridium flare but it happened three times at the same spot and I can’t fathom what it was.

So, based on the star chart app, I can tell it happened next to the star Izar in the constellation Boötis. It happened a short distance south-East of Izar.

At first it looked like an iridium flare, pretty bright brief flash, brighter than Izar but not as bright as say Arcturus near Izar. It last about as long as a lightning bug flashes (there’s no lightning bugs out tonight from what I can tell).

Then about a minute passed and it happened again. And then once more after another minute or so.

The second time was the brightest, the third time was the dimmest. It was the same spot each time.

I’m completely stumped. I’m sure it’s something logical like iridium flare but I don’t know why that would happen in the same spot.

Edit: there’s a star listed as 34 Boötis in the same spot I saw the flashes. Is it possibly connected to this?

Edit 2: a satellite just went past this area so it is a path for satellites I suppose, could help support the idea it was iridium flare and just on three different satellites in close succession?


5 sec flare near Arcturus - Astronomy

Wolf 359 / CN Leo (Leo)
3rd closest star system to the Sun,
7.8 light years distance

Lalande 21185 - 8.3 ly

Lalande 21185 / HIP 54035 lies is Ursa Major at a distance of 8.3 ly.

Lalande 21185 / HIP 54035 (Ursa Major)
4th closest star system to the Sun
Star system with 9th largest proper motion.
/>
Annotated CCD Image (50% size)
7 x 30s (average combine), 1x1 binning, C filter
2006-08-08 21:48h UT (#133011-17)
Motion of Lalande 21185 ( 2006-08-08 + )
[Measured Proper Motion -.- arc sec/year, PA -.- deg
(based on -.-- year observation window) ]
[ cf. Hipparcos Value 4.802"/yr, PA 186.9]

Ross 248 (HH And) - 10.3 ly

Ross 248 (or HH And) lies around 10.3 light years from the sun. It is a main sequence red dwarf and is variable in brightness.

Ross 248 (Andromeda)
Also known as HH And
[ cf. CNS Value : Proper Motion 1.617 "/yr, 177.0 ]
CCD Image
20s exposure, C filter
2005-10-05 19:27h UT (#97044)
Ross 248 (Andromeda)
Reddish tint to Ross 248 is evident in this approximate true colour image
Approximate CCD Image
Clear 20s (C Filter), Red 3x 30s (R), Green 3x 30s (V), Blue 3x 60s(B)
2005-10-05 19:35h UT (#97044-59)
Astrometric solution of Ross 248 at 2005-10-05
based on 65 UCAC2 stars, image scale 1.31 arc sec/pixel
CCD Image
10s exposure, C filter
2005-10-05 19:30h UT (#97047)
Motion of Ross 248 ( 2005-10-5 to 2006-07-24 )
[Measured Proper Motion 1.6 arc sec/year, PA 160.0
(based on 0.80 year observation window) ]
[ cf. Catalog of Nearby Stars (CNS) value 1.617"/yr, 177.0 ]

61 Cygni - Star (The 'flying star') - 11.4 ly

61 Cygni has a significant proper motion of around 5 arc secs/year, and is the reason behind its nickname - the 'flying star' . Friedrich Wilhelm Bessel studied 61 Cygni and was one of the first astronomers to measure annual parallax.

Gliese 725 (HIP 91768) - Double Star - 11.5 ly

Red dwarf binary system, located 11.5 light years from the Sun.

Gliese 725 (Draco)
a pair of red dwarf stars (Struve 2398)
located 11.52 light years away
(15th closest star system to the Sun)

Gliese 725 - detail
showing A and B components
catalog separation 13 arc secs, PA 003 deg
measured separation 12.1 arc secs, PA 356 deg,

catalog proper motion - A: 2.28 arc sec/year, B: 2.31 arc sec/year

Groombridge 34 - Double Star - 11.7 ly

Red dwarf binary system, located 11.7 light years from the Sun. Brightest star is of mag +8.1 with companion star of mag +10.9. Separation measured as 35 arc secs at PA 65 deg. WDS GRB 34 has a proper motion of 2.89 arc secs/year (I hope to record this motion with an image taken in 3-5 years time).

Groombridge 34 AB are both flare stars, like UV Ceti . UV Ceti is an extreme example of a flare star that can boost its brightness by five times in less than a minute, then fall somewhat slower back down to normal luminosity within two or three minutes before flaring suddenly again after several hours.

WDS GRB 34 (Andromeda)
A - GX And, HD 1326
B - GQ And
[ Hipparcos Proper Motion : 2.918"/yr, 081.9 ]
CCD Colour Image
Approximate Colour
Red 1 min (R filter), Green 1 min (V filter), Blue 1 min (B filter)
2005-09-18 20:49h UT (#94008-12)
CCD Image
20 sec exposure, C Filter
2005-09-18 20:45h UT (#84006)
Motion of Groombridge 34 ( 2006 to 2008)
Motion of Groombridge 34 A
[Measured Proper Motion -.- arc sec/year, PA ---.-
(based on -.- year observation window) ]
[ Hipparcos Value ]
Motion of Groombridge 34 B
[Measured Proper Motion -.- arc sec/year, PA ---.-
(based on -.- year observation window) ]
[ Hipparcos Value ]

Gliese 1111 (DX Cnc) - 11.8 ly

Gliese 1111 / DX Cnc (Cancer)

HIP 36208 / GJ 273 ("Luyten's Star") - 12.4 ly

"Luyten's Star" is a nearby red dwarf star, lying approximately 12.4 light years from Earth.

Luyten's Star (Monoceros)

SO025300.5+165258 ("Teegarden's Star") - 12.5 ly

"Teegarden's star" (official name SO025300.5+165258) is a nearby red dwarf star, lying approximately 12.5 light years from Earth. It was discovered was announced in 2003 by a team led by Bonnard J. Teegarden. It has a large proper motion (around 5.1 arc secs per year) and a annual parallax motion of approximately 0.26 arc secs (more information on "Teegarden's Star").
[ Reference Proper Motion 5.106"/yr 138.2 (RECONS) ]

SO025300.5+165258 - "Teegarden's Star" (Aries)

HIP 3829 - Van Maanen's Star - 14.1 ly

HIP 3829 (Pisces)
Van Maanen's Star
(Alt names GJ 35, WD 0046+051, Wolf 28)

Gliese 1245 - star system - 14.8 ly

Gliese 1245 (Cygnus)
(Alt Name V1581 Cyg)
/>
Annotated CCD Image (50% size)
7 x 60s (average median combine), 1x1 binning, C filter
2006-07-23 23:49h UT (#131146-52)
Gliese 1245 - detail
A, B, (C : can't be resolved)
/>
Annotated CCD Image (200% size)
Images details as above
Motion of Gliese 1245 ( 2006-07-24 to 2006-08-08 )
[Measured Proper Motion 1 - 2 arc sec/year, PA 303
(based on 0.04 year observation window) ]
[ cf. Catalog of Nearby Stars (CNS) value 0.731"/yr, 143.1 ]

Gliese 412, star system - 15.8 ly

Gliese 412 (Ursa Major)
Nearby star system - 15.8 light years from the Sun
Binary Star WDS VBS 18
A - HIP 54211
B - GCVS WX UMa (1100+44)
[ Notes : Measured Separation : 31.3 arc secs, PA 126.3 deg
The magnitude for B component (+12.4) appears to be
significantly brighter than its catalog range (+14.2 to +16.5) ]
[ A : Reference Proper Motion 4.511"/yr, 282.1 , Hipparcos]
[ B : Reference Proper Motion 4.531"/yr, 281.9, CNS ]

Groombridge 1618 - 15.9 ly

Groombridge 1618 (Ursa Major)
Nearby star - 15.9 light years from the Sun
(Proper Motion 1.45"/yr)
Alt Name : HIP 49908, Gliese 380

EV Lac (GJ 873, HIP 112460) - 16.5 ly

Altair - 16.7 ly

Altair (Aquila)
16.7 light years from the sun
Mag +0.8
CCD Image,
3 sec exposure, 2x2 binning, C Filter
Log brightness scaling (100-1000 ADU)
2007-10-01 20:06 h UT (#217001)

70 Ophiuchi - Double Star - 17 ly

70 Ophiuchi (Ophiuchus)
This star is a binary system lying 17 light years from Earth
The system has an orbital period of 88 years, with
the pair swinging between 1.6 and 7.0 arc secs
[ Astronomy Now magazine, June 2006 ]
[ Reference Proper Motion 0.19596"/yr, 0.00087, Scholz et al]

Ophiuchi 70 (Ophiuchus) and neighbouring stars
Ophiuchi 70 and some of the neighbouirng stars comprise the multiple star Struve 2272
The following image shows the Ophiuchi 70 as a bright single object,
due to the white-black range used to show the faint neighbouring stars.

Ophiuchi 70 (Ophiuchus) - Close up, colour view
The following image shows the two components as two distinct objects separated
by around 5 arc secs and having noticeably different colours.

Primary star : Yellowish (catalog mag +4.2), Secondary star : Reddish (catalog mag +5.9)
Measured Separation 5.2 +/- 0.5 arc sec, PA : 138 deg +/- 5 deg
FWHM 4.5 arc secs

Gliese 752 - 19.9 ly

Vega - 25.3 ly

Vega (Lyra)
25.3 light years from sun
Mag +0.03
star shows significant glare
CCD Image
20s exposure, C filter
2005-10-02 20:40h UT (#96002)

Groombridge 1830 - 29.9 ly

Groombridge 1830 (Ursa Major)
Nearby star - 29.9 light years from the Sun
Star with 3rd largest proper motion
Alt Name : HIP 57939

HIP 67593 - 43 ly

HIP 67593 (Bootes) - BD+24 2650B
Nearby star 43 light years from the Sun
Star with 6th largest proper motion
Binary Star (WD HJ 2688)
A : HIP 67594
B : HIP 67593
[ Notes : Measured Separation : 29.7 arc secs, PA 292.2 deg ]

Gamma Draconis - Star

Gamma Draconis was the star that the English physicist Robert Hooke made the first 'modern' attempt to detect annual parallax in 1669. His attempt was unsuccessful, and it was not until the 1830's/1840 that Friedrich Wilhelm Bessel and other astronomers first correctly detected parallax using slightly closer stars (eg 61 Cygni). The star is probably too far away for it to show a parallax that can be measured using amateur equipment. However to check this a baseline astrometric measurement of Gamma Draconis' position was made. This task was made difficult as the number of catalog stars directly around the star is limited. To achieve an adequate plate solution the star was moved to one corner of CCD field of view.


Watch the video: Arcturus - Cosmojam (January 2023).