From jop at astro.columbia.edu Sun Mar 4 19:34:12 2018 From: jop at astro.columbia.edu (Joe Patterson) Date: Sun, 4 Mar 2018 19:34:12 -0500 Subject: (cba:news) March stars Message-ID: Dear CBAers, Muchas gracias for all the great data you've been sending, especially re the DQ Her stars which you've been covering so faithfully. It's been a winter of ice and mishap and hard work - nothing really serious but maybe I got kind of soft after a semester off from work. The DQs are relatively sparse in the (northern) springtime sky, so that program can rest - a little. Here are my recommendations for northern observers: 1. AT Cnc. Probably a very ancient nova, and our last campaign showed a credible signal around 28 minutes. Very desirable to get long runs now, the more the better. 2. NY Ser. Reputed to be in a standstill state now around 15.5 - I think the first such event observed in this star's sparse history. Excellent morning target. 3. AM CVn. Perhaps the least exciting star to observe (always within 0.15 mag of 14.2), but very important since it is the prototype of one of the most important classes - the mass-transferring double white dwarfs. We have a TENTATIVE detection of period change through 2016, but a good 2018 season should nail it down. This calls for steady coverage through April (especially) and March. 4. HT Cam. A DQ Her star for which we'd like to get a particularly accurate estimate of period change. 5. BK Lyn. What's it doing this year? Pretty steady, or cycling like the ER UMa stars. Spot checks will be fine, not necessarily time series. And for southern observers: 1. V598 Pup. Lots of activity in this fascinating recent nova. Except for Berto, who always seems to spot the most interesting jewels, we've never observed it before. 2. IM Nor. Back in the sky now. At 18.5, maybe only Gordon can work on it. But some eclipse timings in the new season - i.e. maybe 20-25 hours of coverage - would be great to add to our >95% completed paper on this star. 3. V959 Mon. Another recent nona for which we need the 2018 orbital light curve. It's a long period, so your runs need to be at least 4 hours. 4. WX Pyx. Keep going on this one, the Pdot is still kinda insecure. (I think; Enrique would know for sure). And both hemispheres: SW Sex. We've never done a good job on it, and there's no excuse for it. ALL the SW Sexers have been good to us... so let's give the prototype a chance! Those are my recs. Enrique may send his, of course. joe ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Mon Mar 5 18:15:07 2018 From: jop at astro.columbia.edu (Joe Patterson) Date: Mon, 5 Mar 2018 18:15:07 -0500 Subject: (cba:news) Fwd: monitoring of SDSS1538 In-Reply-To: References: Message-ID: <8ede5d9e-ad77-5051-1342-adf5ecd464e6@astro.columbia.edu> Hi CBAers, Anna has sent this request. The presence of such a hot WD in this short-period binary is indeed a puzzle, and it's possible we could contribute to its solution. The estimated magnitude is 18.6, so it's a daunting challenge for time-series photometry (unless it brightens). However, some of you probably are able to get decent nightly brightness estimates - by averaging, long exposures, etc. I recommend unfiltered since you're likely to need every photon you can get. Be sure to specify your (primary?) comp star, so she can convert it to a quasi-calibrated magnitude. But I don't think a real time series is feasible or even wanted (I'll ask). joe p -------- Forwarded Message -------- Subject: monitoring of SDSS1538 Date: Thu, 15 Feb 2018 11:22:33 +0000 From: Pala, Anna To: jop at astro.columbia.edu Dear Joe, We have been awarded some HST time to observe SDSS J153817.33+512238.0, a short period CV (Porb = 93.11 min) that hosts an?unexpectedly hot?white dwarf?(T ~ 30000K). This high?temperature could be a clue of a nova eruption within the past few 1000 years and the HST observations will help us in?identifying possible ashes and the expanding circumstellar gas shell expected in this case. The HST scheduling team requires us to provide ground based monitoring in order to asses the quiescent state?of the target?prior the HST observations, which should be scheduled in the window March 27 - April 10.More information on the program can be found at this link: http://www.stsci.edu/cgi-bin/get-proposal-info?id=15316&observatory=HST It would be very helpful if the CBA could help us in monitoring this CV. Would it be possible to release an alert notice about this observations? To asses the quiescent state we would need?nightly V/unfiltered observations?starting on the 23rd of February,?a more intense monitoring in the period March 27 - April 10, and then nightly observations again through the end of April. SDSS1538 is a northern target and is?quite faint in quiescence: RA? ? ? ? ? ? ? ? ? ???? Dec? ? ? ? ? ? ? ? V 15 38 17.3410 ?? +51 23 38.04? 18.6 Please, let me know if you need more information. Thank you very much for your help. Kind regards, Anna ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jp42 at columbia.edu Fri Mar 16 18:22:22 2018 From: jp42 at columbia.edu (Joe Patterson) Date: Fri, 16 Mar 2018 18:22:22 -0400 Subject: (cba:news) (cba:chat) March stars In-Reply-To: <1ef9e500-28aa-34ed-1d4c-a35dcb331348@rollinghillsobs.org> References: <1ef9e500-28aa-34ed-1d4c-a35dcb331348@rollinghillsobs.org> Message-ID: Yes, I strongly recommend intense coverage of AT Cnc, for as many hours as you can get it. Best *morning* target for the next 1-2 weeks is AM CVn - also intensive. Duplicating coverage on AM CVn isn't bad - in fact, it's highly desirable.? AM CVn has three periodicities: at 525 s, 1051 s, and 1028 s.? The first two are generally the strongest; but because they're superhumps - not stable on long timescales - they have to be removed in order to track the orbital 1028 s signal.? Somewhat tricky, but can always be done if the data are DENSELY distributed.? That's the key - dense coverage.? This is true for most CBA programs, to some degree - but never as much as AM CVn, because separating these closely spaced frequencies is critical. joe On 3/16/2018 5:03 PM, Shawn Dvorak wrote: > As an extra incentive, AT Cnc is currently in a Z Cam standstill. The > AAVSO data shows it "got stuck" around mag 13.6 near the end of > January. Although the data is a bit sparse, it seems to be showing a > 0.4 mag amplitude variation with a ~6.5 day period. Interesting, but > possibly just a coincidence. It looks like I'll have mostly clear > skies tonight so I'll get a longish run on it from 0:30 - 06:30 UT > > Shawn > > > On 03/04/2018 07:34 PM, Joe Patterson wrote: >> Dear CBAers, >> >> Muchas gracias for all the great data you've been sending, especially >> re the DQ Her stars which you've been covering so faithfully.? It's >> been a winter of ice and mishap and hard work - nothing really >> serious but maybe I got kind of soft after a semester off from work. >> >> The DQs are relatively sparse in the (northern) springtime sky, so >> that program can rest - a little.? Here are my recommendations for >> northern observers: >> >> 1. AT Cnc.? Probably a very ancient nova, and our last campaign >> showed a credible signal around 28 minutes.? Very desirable to get >> long runs now, the more the better. >> >> 2. NY Ser.? Reputed to be in a standstill state now around 15.5 - I >> think the first such event observed in this star's sparse history. >> Excellent morning target. >> >> 3. AM CVn.? Perhaps the least exciting star to observe (always within >> 0.15 mag of 14.2), but very important since it is the prototype of >> one of the most important classes - the mass-transferring double >> white dwarfs.? We have a TENTATIVE detection of period change through >> 2016, but a good 2018 season should nail it down.? This calls for >> steady coverage through April (especially) and March. >> >> 4. HT Cam.? A DQ Her star for which we'd like to get a particularly >> accurate estimate of period change. >> >> 5. BK Lyn.? What's it doing this year?? Pretty steady, or cycling >> like the ER UMa stars.? Spot checks will be fine, not necessarily >> time series. >> >> And for southern observers: >> >> 1. V598 Pup.? Lots of activity in this fascinating recent nova. >> Except for Berto, who always seems to spot the most interesting >> jewels, we've never observed it before. >> >> 2. IM Nor.? Back in the sky now.? At 18.5, maybe only Gordon can work >> on it.? But some eclipse timings in the new season - i.e. maybe 20-25 >> hours of coverage - would be great to add to our >95% completed paper >> on this star. >> >> 3. V959 Mon.? Another recent nona for which we need the 2018 orbital >> light curve.? It's a long period, so your runs need to be at least 4 >> hours. >> >> 4. WX Pyx.? Keep going on this one, the Pdot is still kinda insecure. >> (I think; Enrique would know for sure). >> >> And both hemispheres: SW Sex.? We've never done a good job on it, and >> there's no excuse for it.? ALL the SW Sexers have been good to us... >> so let's give the prototype a chance! >> >> Those are my recs.? Enrique may send his, of course. >> >> joe >> >> ____________________________________________________________ >> Center for Backyard Astrophysics (CBA) mailing lists >> https://cbastro.org/communications/mailing-lists/ > > > > ____________________________________________________________ > Center for Backyard Astrophysics (CBA) mailing lists > https://cbastro.org/communications/mailing-lists/ ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Tue Mar 20 06:41:54 2018 From: jop at astro.columbia.edu (Joe Patterson) Date: Tue, 20 Mar 2018 06:41:54 -0400 Subject: (cba:news) Fwd: ATel 11448. ***Instant Email Notice***: Transients In-Reply-To: <20180320091704.5F8931B0003B@sedna.astro.columbia.edu> References: <20180320091704.5F8931B0003B@sedna.astro.columbia.edu> Message-ID: <14c37588-bfd7-a090-507c-09c5eda23085@astro.columbia.edu> Well, it would be criminal not to forward this one! Cloudy in NYC... but look outside! joe -------- Forwarded Message -------- Subject: ATel 11448. ***Instant Email Notice***: Transients Date: Tue, 20 Mar 2018 05:17:04 -0400 (EDT) From: atel at astronomerstelegram.org To: jop at astro.columbia.edu ***Instant Email Notice***: Transients ------------------------------------------------------------------------------ ------------------------------------------------------------------------------ The Astronomer's Telegram http://www.astronomerstelegram.org ============================================================================== ATEL #11448 ATEL #11448 Title: Very bright optical transient near the Trifid and Lagoon Nebulae Author: Peter Dunsby (University of Cape Town) Queries: Peter.Dunsby at uct.ac.za Posted: 20 Mar 2018; 09:14 UT Subjects:Transient Peter Dunsby (University of Cape Town) reports the detection of a very bright optical transient in the region between the Lagoon and Trifid Nebulae based on observations obtained from Cape Town on 20 March 2018, between 01:00 and 03:45 UT. The object was visible throughout the full duration of the observations and not seen when this field was observed previously (08 March 2018). The optical transients is at least first magnitude and is located at the following coordinates: RA (2000): 18h 04m 50s Declination (2000.0): -23d 29m 58s The coordinates are accurate to a few arcseconds. There is no obvious counterpart at this position on the Digital Sky Survey plates. Observations were obtained using an 80mm refractor. The attached URL show the image of this field (2.3 x 1.7 degrees, plate scale of 9 arcseconds per pixel) on 20 March 2018. The optical transient is the brightest star in the field. Further observations are strongly encouraged to establish the nature of this very bright optical transient. ------------------------------------------------------------------------------ Password Certification: Patrick Woudt (pwoudt at ast.uct.ac.za) http://www.astronomerstelegram.org/?read=11448 ============================================================================== ============================================================================== This is an automatically-generated notice. You can remove yourself permanently from receiving both the Daily Email Digest and Instant Email Notices from The Astronomer's Telegram by following this link: http://www.astronomerstelegram.org?unsubscribe&confirmation=f36bf01d7c5404632bfc7d5e71268966&address=jop at astro.columbia.edu ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Tue Mar 20 06:49:03 2018 From: jop at astro.columbia.edu (Joe Patterson) Date: Tue, 20 Mar 2018 06:49:03 -0400 Subject: (cba:news) Martian invasions In-Reply-To: <20180320095611.243EF1B0003F@sedna.astro.columbia.edu> References: <20180320095611.243EF1B0003F@sedna.astro.columbia.edu> Message-ID: Aha... and it's not even Halloween, and the sighting wasn't even in Grovers Mill, New Jersey. The might sky has been so starved of planets lately, it's easy to forget they're out there! BTW thanks for all the response to the AM CVn request - and keep it up! joe p -------- Forwarded Message -------- Subject: ATel 11449. ***Instant Email Notice***: Transients Date: Tue, 20 Mar 2018 05:56:11 -0400 (EDT) From: atel at astronomerstelegram.org To: jop at astro.columbia.edu ***Instant Email Notice***: Transients ------------------------------------------------------------------------------ ------------------------------------------------------------------------------ The Astronomer's Telegram http://www.astronomerstelegram.org ============================================================================== ATEL #11449 ATEL #11449 Title: Erratum to ATel #11448: Very bright optical transient near the Trifid and Lagoon Nebulae Author: Peter Dunsby (University of Cape Town) Queries: Peter.Dunsby at uct.ac.za Posted: 20 Mar 2018; 09:54 UT Subjects:Optical The object reported in ATel 11448 has been identified as Mars. Our sincere apologies for the earlier report and the inconvenience caused. ------------------------------------------------------------------------------ Password Certification: Patrick Woudt (pwoudt at ast.uct.ac.za) http://www.astronomerstelegram.org/?read=11449 ============================================================================== ============================================================================== This is an automatically-generated notice. You can remove yourself permanently from receiving both the Daily Email Digest and Instant Email Notices from The Astronomer's Telegram by following this link: http://www.astronomerstelegram.org?unsubscribe&confirmation=f36bf01d7c5404632bfc7d5e71268966&address=jop at astro.columbia.edu ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jp42 at columbia.edu Thu Mar 22 08:07:45 2018 From: jp42 at columbia.edu (Joe Patterson) Date: Thu, 22 Mar 2018 08:07:45 -0400 Subject: (cba:news) Fwd: Re: (cba:chat) CR Boo faint In-Reply-To: References: Message-ID: Hi CBAers, CR Boo at 16.7 is a RARE opportunity, and it's available to both hemispheres for lengthy observation. It's an urgent priority now.? There's not much historical evidence about the duration of these low states - maybe only a few days.? It's a get-thee-to-a-telescope moment.? The main periodicity is near 25 minutes, so you don't have any special constraints about integration time. joe p -------- Forwarded Message -------- Subject: Re: (cba:chat) CR Boo faint Date: Thu, 22 Mar 2018 02:00:43 -0400 From: Shawn Dvorak Reply-To: cba-chat at cbastro.org To: cba-chat at cbastro.org I'm not sure if CR Boo is still an object of interest, but it's currently in a low state. I just measured it (05:45 UT) at v=16.7. I'm going to go ahead and follow it until it gets too late, so I should be about 4.5 hours of data. Shawn On 05/30/2017 12:40 PM, Joe Patterson wrote: > 16.0 isn't quite DefCon 5, but it's at least DefCon 3.? I've only > personally seen it once that faint in a few hundred hours of observing, > and I only had a spectrograph on the telescope that night.? Good (at > least) target for all known hemispheres. > > And for spectroscopy too, if those people are reading. > > joe p > > On 5/30/2017 9:42 AM, Joe Ulowetz wrote: >> Last night CR Boo was around mag 16.0.? It isn't quite to the mag 17 >> level that Joe P. said constituted an alert for this star, but it is >> fainter than the mag 14-15 that I usually see it at. >> >> It seemed to be brightening slightly toward the end of the night. >> >> Joe U. >> >> >> Inline image 1 >> >> >> ____________________________________________________________ >> Center for Backyard Astrophysics (CBA) mailing lists >> http://cbastro.org/communications/mailing-lists/ >> > ____________________________________________________________ > Center for Backyard Astrophysics (CBA) mailing lists > http://cbastro.org/communications/mailing-lists/ ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Thu Mar 22 09:09:53 2018 From: jop at astro.columbia.edu (Joe Patterson) Date: Thu, 22 Mar 2018 09:09:53 -0400 Subject: (cba:news) Fwd: AAVSO Alert Notice 625: ASASSN-18ey = MAXI J1820+070 coverage needed for VLT and XMM In-Reply-To: <3ad9dedd265a0351968ebddee.fa039ca03c.20180321193624.8e5d7ffd40.87fb21a2@mail17.sea31.mcsv.net> References: <3ad9dedd265a0351968ebddee.fa039ca03c.20180321193624.8e5d7ffd40.87fb21a2@mail17.sea31.mcsv.net> Message-ID: Hi CBAers, This is right up our alley too - not just for the HST window, but for time series after the HST observation also. Since everyone will have airmass problems in the eastern predawn sky, feel free to stretch your limits if you have a decent night - maybe as far as 3 airmasses. Pick it up as soon as you can. I know it conflicts somewhat with the CR Boo alert I just sent... but give the MAXI priority if it's available for observation. With such a short observation window, there may be pretty scant data obtained. joe -------- Forwarded Message -------- Subject: AAVSO Alert Notice 625: ASASSN-18ey = MAXI J1820+070 coverage needed for VLT and XMM Date: Wed, 21 Mar 2018 19:37:18 +0000 From: AAVSO Reply-To: AAVSO To: jop at astro.columbia.edu AAVSO Alert Notice 625: ASASSN-18ey = MAXI J1820+070 coverage needed for VLT and XMM AAVSO Alert Notice 625 *ASASSN-18ey = MAXI J1820+070 coverage needed for VLT and XMM* /*March 21, 2018*/: Dr. Tom Maccarone (Texas Tech University) has requested AAVSO observers' assistance in monitoring the outbursting black hole X-ray binary ASASSN-18ey = MAXI J1820+070 in support of VLT and XMM observations scheduled for: *29018 22 March 08-09:30 UT? and? 29 March 08-09:30 UT* V time series are requested, with as short a cadence as possible (ideally, a time resolution of 0.1 second or better). Please see /AAVSO Alert Notice 624/ for more information about this object. ASASSN-18ey = MAXI J1820+070 has a published optical range of 12.5 CV - 18.3: V. The most recent observations submitted to the AAVSO International Database are: 2018 Mar. 20.38034 UT, 12.557 CV +/-0.015 (F.-J. Hambsch, Mol, Belgium); 20.38014, 12.341 CV +/-0.014 (Hambsch); 20.37994, 12.511 CV +/-0.016 (Hambsch); 20.37973, 12.426 CV +/-0.015 (Hambsch); 20.37953, 12.413 CV +/-0.015 (Hambsch); 20.37934, 12.535 CV +/-0.016 (Hambsch); 20.37913, 12.485 CV +/-0.016 (Hambsch); Coordinates (2000.0):? R.A. 18 20 21.95?? Dec. +07 11 07.3 Charts with a comparison star sequence for ASASSN-18ey may be created using the AAVSO Variable Star Plotter (VSP) . You may use either ASASSN-18ey or MAXI J1820+070 as the name when creating a chart. Please submit observations to the AAVSO International Database using the name ASASSN-18ey. This observing campaign is being followed on the AAVSO Time Sensitive Alerts online forum at https://www.aavso.org/asassn-18ey-suspected-black-hole-binary-bright-outburst This AAVSO Alert Notice was compiled by Elizabeth O. Waagen. ---------------------------------- SUBMIT OBSERVATIONS TO THE AAVSO Information on submitting observations to the AAVSO may be found at: https://www.aavso.org/webobs ALERT NOTICE ARCHIVE AND SUBSCRIPTION INFORMATION An Alert Notice archive is available at the following URL: https://www.aavso.org/aavso-alert-notices-for-observing-campaigns-and-discoveries Subscribing and Unsubscribing may be done at the following URL: https://www.aavso.org/aavso-alert-notice-subscribe ------------------------------------------------- Please support the AAVSO and its mission -- Join or donate today: https://www.aavso.org/apps/donate/ /Copyright ? 2018 American Association of Variable Star Observers, All rights reserved./ You are receiving this email because you subscribed to the AAVSO Alert Notices. If you wish to unsubscribe, please go to your "My account" page on the AAVSO website and unclick the "Alert Notices" box under the "Email settings" tab. Thank you. *Our mailing address is:* American Association of Variable Star Observers 49 Bay State Rd. Cambridge, MA 02138 Add us to your address book Want to change how you receive these emails? You can update your preferences or unsubscribe from this list ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Mon Mar 26 14:55:32 2018 From: jop at astro.columbia.edu (Joe Patterson) Date: Mon, 26 Mar 2018 14:55:32 -0400 Subject: (cba:news) am cvn Message-ID: Dear CBAers, Let's gang up on AM CVn one last time. We're doing a long-term study of the Porb. It's clear now - from the last 25 years of timings - that Porb is slowly decreasing. This will surprise most AM CVn fans and will inspire some re-thinking of our assumptions. But the rate of period change is critical, and depends most critically on the accuracy of timings near the beginning and end of the interval (1992-2018). We can't improve 1992. But we can definitely gang up on 2018. So far, led by Joe U, we've done OK. But we have to keep up the pressure, and European coverage, especially, has been somewhat sparse. It's a perfect time of year - crossing the meridian near local midnight - for long runs. Long runs are especially desirable here because we have to distinguish the 1028 s ORBITAL from the two superhump signals (at 1051/525 and 1011 s) which make a lot of mischief. joe ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jop at astro.columbia.edu Sat Mar 31 05:57:08 2018 From: jop at astro.columbia.edu (Joe Patterson) Date: Sat, 31 Mar 2018 05:57:08 -0400 Subject: (cba:news) MAXI J1820 = ASASSN-18ey URGENT Message-ID: Hi CBAers, Can you immediately send any data - just a snapshot magnitude would be great - you have gathered on this star in the last two days? And if you don't have any, can you immediately get one. Just one magnitude would be great! The HST observation window is imminent, and the brightness is critical to pass the test for observation (a go/no-go). joe p ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/ From jp42 at columbia.edu Sat Mar 31 07:32:28 2018 From: jp42 at columbia.edu (Joe Patterson) Date: Sat, 31 Mar 2018 07:32:28 -0400 Subject: (cba:news) (cba:chat) MAXI J1820 = ASASSN-18ey URGENT In-Reply-To: <548778c6-adce-ed6b-cb5b-a939e9950e1a@earthlink.net> References: <32782a04e9354d8080df4b7962da99c6@ex04mail01b.ad.rit.edu> <548778c6-adce-ed6b-cb5b-a939e9950e1a@earthlink.net> Message-ID: Still dark on the West Coast, and later in AU/NZ, when the HST will still be observing.? Of course, simultaneous observations are pure gold.? "Contemporaneous" (close in time) observations are mighty good too.? We don't know much about periods in this star, but short integrations are preferred if you have experience with them.? There is merit in both unfiltered observation (better S/N) and filtered (so it can be put on a flux versus wavelength curve). joe On 3/31/2018 7:18 AM, Geoff Stone wrote: > > I just took a few shots and am seeing 11.9 - 12.12 > > Geoff > > > On 3/31/2018 3:57 AM, Joe Ulowetz wrote: >> My conditions weren't great tonight, but I measured between 11.9 and >> 12.3 from?2458208.82 -?208.87 >> >> -Joe U. >> >> >> Virus-free. www.avg.com >> >> >> >> >> On Sat, Mar 31, 2018 at 5:25 AM, Michael Richmond > > wrote: >> >> >> ? I've been making measurements of the object over the >> past three hours: JD 2458208.78 - 208.90.? During this period, >> the variable has been pretty steady at V = 12.1-12.0, with >> short-term fluctuations. >> >> ? ? ? ? ? ? ? MWR >> >> ________________________________________ >> From: cba-news [cba-news-bounces at cbastro.org >> ] on behalf of Joe Patterson >> [jop at astro.columbia.edu ] >> Sent: Saturday, March 31, 2018 5:57 AM >> To: cba-news at cbastro.org ; >> cba-chat at cbastro.org >> Subject: (cba:news) MAXI J1820 = ASASSN-18ey URGENT >> >> Hi CBAers, >> >> Can you immediately send any data - just a snapshot magnitude >> would be >> great - you have gathered on this star in the last two days?? And >> if you >> don't have any, can you immediately get one.? Just one magnitude >> would >> be great!? The HST observation window is imminent, and the >> brightness is >> critical to pass the test for observation (a go/no-go). >> >> joe p >> >> ____________________________________________________________ >> Center for Backyard Astrophysics (CBA) mailing lists >> https://cbastro.org/communications/mailing-lists/ >> >> ____________________________________________________________ >> Center for Backyard Astrophysics (CBA) mailing lists >> https://cbastro.org/communications/mailing-lists/ >> >> >> >> >> >> ____________________________________________________________ >> Center for Backyard Astrophysics (CBA) mailing lists >> https://cbastro.org/communications/mailing-lists/ > > > > ____________________________________________________________ > Center for Backyard Astrophysics (CBA) mailing lists > https://cbastro.org/communications/mailing-lists/ ____________________________________________________________ Center for Backyard Astrophysics (CBA) mailing lists https://cbastro.org/communications/mailing-lists/