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Ulrich Elkmann Offline




Beiträge: 8.089

05.01.2020 02:51
Beteigeuze Antworten

Es gibt ja den guten Ratschlag, zum Auftakt eines Film - oder eines Blogjahres - "mit einem Erdbeben zu beginnen und sich dann langsam zu steigern".

Galaktischer wird's nicht.



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

14.01.2020 10:06
#2 RE: Beteigeuze Antworten

Zitat von Livescience.com, 8 Jan. 2020
The giant red star Betelgeuse might be harboring a gruesome secret in its past. A new model posits that the prominent night-sky object was once two stars, until the larger star ate its smaller companion. And that could explain several of Betelgeuse's peculiar properties.
...
By closely monitoring Betelgeuse's surface, different researchers have calculated that the star's rotational rate is somewhere between 11,000 and 33,000 mph (17,700 to 53,000 km/h), Manos Chatzopoulos, an astronomer at Louisiana State University in Baton Rouge, said during a session on Monday (Jan. 6) at the 235th meeting of the American Astronomical Society here.

This is surprising because as a star ages and enters the red giant phase of its life, like Betelgeuse has, the star expands and its rotation typically slows down, much like an ice skater pushing out their arms to slow their spin, Chatzopoulos told Live Science.

Betelgeuse is also a runaway star, meaning that the object is zipping along at a mind-boggling speed, in Betelgeuse's case, 67,000 mph (108,000 km/h) relative to background stars in the Milky Way, he added.

"For such a famous star that everyone knows and loves, nobody has tried to explain the combination of these two things," Chatzopoulos said, referring to its odd rotation rate and speed. "So how do you put together these two facts?"

A clue might come from where Betelgeuse is thought to originate, a star-dense region known as the Orion OB1a association. Along with colleagues, Chatzopoulos has suggested that gravitational interactions with the many stars in that region could have flung Betelgeuse away at high speed millions of years ago, explaining the star's hyper-velocity.

Betelgeuse might have also had a smaller companion, the researchers posited, which got tossed out along with it. As Betelgeuse aged and expanded, it might have engulfed this partner, which would have stirred up Betelgeuse's outer layers "like stirring up coffee with a stick," Chatzopoulos said, and increased its rotation rate.

He and his collaborators have run sophisticated stellar-evolution computer models incorporating all these ideas. The results that best fit Betelgeuse’s observed features suggested it was once two separate stars, one with 16 times the sun's mass and another with four times the sun's mass. The researchers are preparing to submit their research to The Astrophysical Journal.

The researchers' models were also able to match the amount of nitrogen seen in Betelgeuse's atmosphere, which is unusually high. This is a potentially corroborating piece of evidence, because the stirring of a companion star might have dredged up nitrogen from Betelgeuse's center, Chatzopoulos said.

Earlier work by Chatzopoulos' former Ph.D. advisor offered the idea that Betelgeuse was formed as the merger of two stars. Chatzopoulos said that his new research expands on that prior idea and adds in specific simulations to account for the red giant star's rotation and speed.



https://www.livescience.com/betelgeuse-m...-two-stars.html



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

15.01.2020 22:25
#3 RE: Beteigeuze Antworten

https://earthsky.org/space/ligo-gravitat...near-betelgeuse

Zitat
It’s probably nothing: Gravitational wave burst detected near Betelgeuse
Posted by Deborah Byrd in HUMAN WORLD | SPACE | January 15, 2020

Betelgeuse has dimmed recently, prompting some to wonder if it’s about to explode. An explosion might trigger a gravitational wave burst. Betelgeuse is still there. The nearby gravitational wave burst probably means nothing for this star. Still …

The Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo detectors recorded a “burst” of gravitational waves this week, from an area of sky near the red supergiant Betelgeuse. This unanticipated burst has been dubbed, for now, S200114f. It’s prompting some interesting chatter on Twitter because Betelgeuse has undergone an unusual dimming in recent weeks, and some astronomy enthusiasts have wondered if it were about to explode. Betelgeuse has not exploded. It’s still there. Still, a supernova explosion of Betelgeuse might be linked with a gravitational wave burst. As Jackson Ryan explained on CNET last night (January 14, 2020):

The gravitational waves we’ve detected so far usually relate to extreme cosmic events, like two black holes colliding or neutron stars finally merging after being caught in a death spiral. Burst gravitational waves have not been detected before and scientists hypothesize they may be linked to phenomena such as supernova or gamma ray bursts, producing a tiny ‘pop’ when detected by the observatories.



Zitat
Andy Howell
@d_a_howell
MehrAndy Howell hat Dr. Jessie Christiansen retweetet
Update on the Gravitational Wave burst from last night:
- Betelgeuse is still there (as expected)
- 400 sq. deg. is a large area - too big for most
- You can see where telescopes have/are pointing here: http://treasuremap.space/alerts?graceids...ng_status=pandc
- ZTF has some faint candidates to investigate

08:38 - 14. Jan. 2020



https://twitter.com/d_a_howell/status/1217123788657049601

Zitat
Andy Howell
‏@d_a_howell
Also, from the lack of detection of neutrinos by KM3Net/ORCA, they calculate a lower limit on the distance for a core collapse origin of 6.1 kpc, or 20,000 lightyears. So not Betelgeuse! https://gcn.gsfc.nasa.gov/gcn3/26751.gcn3
15:50 - 14. Jan. 2020



https://twitter.com/d_a_howell/status/1217232474259877888



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

20.01.2020 13:48
#4 RE: Beteigeuze Antworten

Zitat
Andy Howell
‏Verifizierter Account @d_a_howell

Andy Howell hat Corey S. Powell retweetet

This depiction is right. When #Betelgeuse explodes it will be nearly as bright as the full moon and obvious all over the world. It will make astronomy an international conversation and inspire millions. Has anyone studied how wildlife will be affected?
11:59 - 17. Jan. 2020


https://twitter.com/d_a_howell/status/1218261576379068416


Zitat
Mauro Aguirre
‏ @MauroAguirreBr
17. Jan.
Some one should make an ultra realistic CGI of what the Betelgeuse super nova will look like from earth. This will maybe satisfy a little this desire to see the real thing.
Corey S. Powell
‏ @coreyspowell
Antwort an @MauroAguirreBr
This is the only realistic attempt I've seen so far to show what a #Betelgeuse supernova might look like. https://www.youtube.com/watch?v=_VjZdxgIMs4



Dieses Video.



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

21.01.2020 13:17
#5 RE: Supernvae als 'Standardkerzen' Antworten

Zu Supernovae als "Standardkerzen" für die Bestimmung kosmischer Entfernungen und, hier, die Hypothese der "dunklen Energie" als postuliertem Antrieb hinter der sich beschleunigenden Expansion des Weltalls. Wir haben eine neue Grundkontroverse in der Kosmologie.

"New evidence shows that the key assumption made in the discovery of dark energy is in error"

Zitat
"The team has performed very high-quality (signal-to-noise ratio ~175) spectroscopic observations to cover most of the reported nearby early-type host galaxies of SN Ia, from which they obtained the most direct and reliable measurements of population ages for these host galaxies. They find a significant correlation between SN luminosity and stellar population age at a 99.5 percent confidence level. As such, this is the most direct and stringent test ever made for the luminosity evolution of SN Ia. Since SN progenitors in host galaxies are getting younger with redshift (look-back time), this result inevitably indicates a serious systematic bias with redshift in SN cosmology.

Other cosmological probes, such as the cosmic microwave background (CMB) and baryonic acoustic oscillations (BAO), are also known to provide some indirect and "circumstantial" evidence for dark energy, but it was recently suggested that CMB from Planck mission no longer supports the concordance cosmological model which may require new physics (Di Valentino, Melchiorri, & Silk 2019). Some investigators have also shown that BAO and other low-redshift cosmological probes can be consistent with a non-accelerating universe without dark energy (see, for example, Tutusaus et al. 2017). In this respect, the present result showing the luminosity evolution mimicking dark energy in SN cosmology is crucial and very timely.

This result is reminiscent of the famous Tinsley-Sandage debate in the 1970s on luminosity evolution in observational cosmology, which led to the termination of the Sandage project originally designed to determine the fate of the universe."


https://phys.org/news/2020-01-evidence-k...weekly-nwletter

Preprint-Version des Papers: https://arxiv.org/abs/1912.04903 (51 Seiten)

Zitat
Nevertheless, to test the effect of luminosity evolution, in the discovery papers, Riess et al. (1998), Schmidt et al. (1998), and Perlmutter et al. (1999) only used morphological classification of host galaxies in the local universe as a proxy for stellar population age. Because of apparently very small difference in the standardized brightness between SNe Ia in the early-type and late-type host galaxies, they concluded that the luminosity evolution is negligible in SN cosmology. Later analysis based on a larger sample by Hicken et al. (2009), however, found a systematic difference of ∼0.14 mag between the very early- and very late-type galaxies (see also Suzuki et al. 2012). Recent investigations of host galaxies further found a correlation between the SN brightness1and host mass, suggesting that SNe Ia in less massive galaxies are ∼0.1 mag fainter than those in more massive galaxies (Kelly et al. 2010; Sullivan et al. 2010; Childress et al. 2013; Johansson et al. 2013). More recent studies based on star formation rate (SFR) in host galaxies also showed that the SNe Ia in locally star-forming environments are fainter than those in locally passive environments (Rigault et al. 2015; Kim et al. 2018; Rigault et al. 2018; Roman et al. 2018; Rose et al. 2019). (p.3)




Die Debatte zwischen den Positionen von Allen Sandage und Beatrice Tinsley ab 1972 drehte sich um den Wert der Hubble-Kosnante H; Sandage taxierte die nach der Entdeckung der ersten radiogalaxien 1967 auf einen Wert von 50 und kam damit auf ein Alter des Universums von 20 Milliarden Jahren; Tinsley vermutete, daß Galaxien im frühen Universum lichtschwächer gewesen seien und kan auf die Hälfte des Alters. Übrgiens nicht die erste Kontroverse dieser Art: die vorhergehende war die Entdeckung in den 1940er Jahren, daß es zwei Klassen von Cepheiden gab, wodurch sich die Entfernungen zu den dadurch bestimmten Galaxien auf einen Schlag verdopppelten.



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

27.01.2020 00:37
#6 RE: Supernvae als 'Standardkerzen' Antworten

"Betelgeuse is Continuing to Dim! It’s Down to 1.506 Magnitude"

Zitat von Universe Today.com 22 Jan 2020
Villanova University astronomers Edward Guinan and Richard Wasatonic were the first to report Betelgeuse’s recent dimming. In a new post on The Astronomer’s Telegram, the pair of astronomers report a further dimming of Betelgeuse. They also point out that although the star is still dimming, its rate of dimming is slowing.

Betelgeuse is a red supergiant star in the constellation Orion. It left the main sequence about one million years ago and has been a red supergiant for about 40,000 years. It’s a core-collapse SN II progenitor, which means that eventually, Betelgeuse will burn enough of its hydrogen that its core will collapse, and it will explode as a supernova.



https://www.universetoday.com/144694/bet...-506-magnitude/

http://www.astronomerstelegram.org/?read=13410

Zitat
The Continued Unprecedented Fading of Betelgeuse
ATel #13410; Edward F. Guinan and Richard J. Wasatonic (Villanova University)
on 20 Jan 2020; 17:50 UT

We report further on the recent unusual dimming of the red supergiant Betelgeuse (alpha Ori) reported previously in ATel #13341 and ATel #13365. We continue to carry out V-band and Wing TiO and near-IR photometry of the star. Since our last report, Betelgeuse has continued to gradually decrease in brightness. Our most recent photometry secured on 17.25 UT and 18.20 UT January 2020 yields: V = +1.494 mag and 1.506 mag, respectively. This is more than ~0.2 mag fainter than previously reported in ATel #13365 on 22.25 UT Dec. 2019. However during the last week or so the decline in brightness of the star may be slowing. As reported by Brian Skiff of Lowell Observatory (priv. commun.) visual estimates of Betelgeuse are available as far back as about 180-years ago. Systematic visual measures of the star have been made by AAVSO observers since the 1920s. More precise photoelectric photometry began nearly 100 yrs ago but systematic (mostly unpublished) photometry of Betelgeuse commenced about 40-years ago at Villanova Observatory by Scott Wacker and Guinan. Betelgeuse is now nearly as faint as (the slightly variable) B2 star Bellatrix (V ~+1.62 mag). Bellatrix (gamma Ori) is about 5° west of Betelgeuse in the constellation Orion. The analysis of the calibrated Wing photometry (Wing 1992: JAAVSO 21, 42) returns measures of the temperature (via calibrated Wing TiO- and near-IR (B-C) color-indices) as well as estimates of bolometric magnitude (m-bol). The Wing intermediate band A-filter is used to measure the temperature-sensitive TiO 719-nm (gamma; 0, 0) molecular band. The B (750-nm) and C (1020.4-nm) filters are centered on relatively line-free stellar continuum regions. The C-band filter measures have been calibrated with K-M stars with bolometric magnitudes returning proxy measures of the apparent bolometric magnitude (m-bol) (see Wasatonic et al. 2015: PASP, 127, 1010). During the 25-years of V-band / Wing Near-IR photometry, Betelgeuse is currently the coolest and least luminous yet observed. Since September 2019, the star's temperature has decreased by ~100 K while its luminosity (inferred from the C-band/m-bol observations) has diminished by nearly 25%. At face value using R'/R = [(T'/T)^4 / L'/L]^0.5 (where R', T' and L' are the current values of stellar Radius, Temperature & Luminosity), this implies an increase of the star's radius of ~9%. However, as pointed out by others, the current fainting episode could also arise from expelled, cooling gas/dust partially obscuring the star. The recent changes defined by our V-band/Wing photometry seem best explained from changes in the envelop-outer convection atmosphere of this pulsating, unstable supergiant. If these recent light changes are due to an extra-large amplitude light pulse on the ~420-day period, then the next mid-light minimum is expected during late January/early February, 2020. If Betelgeuse continues to dim after that time then other possibilities will have to be considered.



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

30.01.2020 13:50
#7 RE: Supernvae als 'Standardkerzen' Antworten

Zitat von Sky and Telescope, 29 Jan 2020
To see what Betelgeuse is up to anytime visit the AAVSO website. In the Pick a Star box, type Betelgeuse then either select Check Recent Observations or Plot a Light Curve. You can input your own parameters by selecting Plot Another Curve in the top left-hand corner. In the dialog boxes, you can include all observations in every color band or choose specific types such as visual, red, or V-band, for example. You can also toggle between Julian and calendar dates, and under Preferences you can set your magnitude scale.



https://www.skyandtelescope.com/observin...-comet-iwamoto/

https://www.aavso.org/LCGv2/



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

04.02.2020 12:24
#8 RE: Supernvae als 'Standardkerzen' Antworten

Zitat
Betelgeuse Updates

ATel #13439; Edward F. Guinan and Richard J. Wasatonic (Villanova University) on 1 Feb 2020; 23:20 UT

We give an update on the star's recent behavior and also correct an error in our prior telegram (ATel #13410). Although the decrease in brightness appears to have slowed, our most recent observation on 30.15 UT, January 2020 is V = +1.614 +/-0.012 mag. The average of our last three measures over the prior 10-days is = +1.58 mag. Our V-mag measures are in very good agreement with corresponding values found by AAVSO observers. Betelgeuse is now ~1.0 mag fainter relative to observations made at the start of 2019/20 observing season during September. As discussed in the previous telegrams, Wing TiO and near-IR photometry returns measures of the star’s temperature (T) from TiO 719-nm band-head feature relative to the nearby reference continuum (the Wing B-filter at 752-nm). The Wing C-band filter (1024-nm) is centered on a (mostly) line-free spectral region near the peak of the M-star's spectral energy distribution (see Wing 1992: JAAVSO 21, 42). The Wing C-band observations serve as proxies for apparent bolometric magnitudes (m-bol) from which the star's luminosity(L) can be estimated. The analyses of the updated Wing ABC measures return estimates of Teff (T) and Luminosity (L). The recent mean values (T', L', R') were computed from observations made during the last 10-days of January 2020. These are compared with measures from September 2019 (L, T, R) made during the local light maximum. The star's radius (R) is estimated from L = 4 pi R^2 -sigma T^4. Correcting the error in our previous ATel (thanks to George Cooper for pointing this out), the change in radius R'/R is calculated from R'/R = [(L'/L)/(T'/T)^4 ]^0.25. Adopting T'/T = (3565 K /3650 K), and L'/L = 0.77, indicates an apparent radius decrease of R'/R ~0.92 since September 2019. But as a caveat, this estimate is bolometric-based and assumes the changes originate from a spherically symmetric star.



http://www.astronomerstelegram.org/?read=13439



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

08.02.2020 17:42
#9 RE: Supernvae als 'Standardkerzen' Antworten

Beteigeuze: täglicher Status auf Twitter.

https://twitter.com/betelbot/status/1225857876801003522

Zitat
Betelgeuse Status
@betelbot

Now at 37% of my usual brightness!

8:04 nachm. · 7. Feb. 2020



Zitat
Betelgeuse Status
@betelbot
My visual mag from last night was 1.65 (robust mean of 11 observations). That is 0.06 mag dimmer than the robust mean of the 5 previous nights (n=87, 1.8σ). #Betelgeuse

3:03 nachm. · 8. Feb. 2020·betelbot



Ich vermeine das sogar mit unbewaffnetem Auge wahrnehmen zu können (bei klarem Himmel kann ich zurzeit Orion und Sirius von meinem Schreibtisch aus aufgehen sehen). Aber da mag die Erwartung die Wahrnehmung beeinflussen.



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

F.Alfonzo Offline



Beiträge: 723

09.02.2020 14:13
#10 RE: Supernvae als 'Standardkerzen' Antworten

Zitat von Ulrich Elkmann im Beitrag #9
Beteigeuze: täglicher Status auf Twitter.




Wie sich an den überaus witzigen Kommentaren ("blow up already!!") unschwer erkennen lässt, haben wir es hier mit einem Paradebeispiel dafür zu tun, dass ein Medium in seiner Dynamik halbwegs zu jener der Objekts passen sollte, über das berichtet wird.

Twitter eignet sich hervorragend, um bspw. über den aktuellen Stand eines Fussballspiels zu informieren. Über Ereignisse von kosmischer Dauer sollte man dann vielleicht doch eher ein Buch schreiben... oder eine Bibliothek. Die böte - im Gegensatz zu Twitter - darüberhinaus zumindest noch die theoretische Chance, dass die gesammelten Daten bei Eintritt des Sternentods in drölfzigtausend Jahren tatsächlich noch existieren. Besser noch wäre vermutlich eine Höhlenmalerei...

Ulrich Elkmann Offline




Beiträge: 8.089

09.02.2020 17:36
#11 RE: Supernvae als 'Standardkerzen' Antworten

Zitat von F.Alfonzo im Beitrag #10
Twitter eignet sich hervorragend, um bspw. über den aktuellen Stand eines Fussballspiels zu informieren.


Wir haben es hier ja genau mit dieser Dynamik zu tun: Momentaner Ist-Stand. Im Kosmos läuft es entweder in Jahrmillionen oder im Sekundentakt. Den Hintergrund habe ich (und die anderen zum Thema) ja anderweitig mitgeliefert. Die Natur des Sekundenmediums Twitter bringt es mit sich, daß man nur die jeweilige Meldung zu beachten hat und den Rattenschwanz der Reaktionen schlicht ignorieren muß. Wir sehen das ja exemplarisch bei @realDonaldTrump, wo i.d.R. in dem gefühlt erstem Tausend der auflaufenden Kommentare nur Geheule & Gepfeife vernehmbar ist. Wer Twitter-Kommentare zur Kenntnis nimmt, ist selbst schuld. Man bekommt die Kommis ja nur angezeigt, wenn man die Einzeltweets anklickt (was ich in diesem Fall gemacht hatte) & sich nicht den Gesamtstrang anschaut. Dort sieht man dann im Turnus den Stand der aktuellen Messungen, der Werte der letzen 120 Tage, und die mathematische Extrapolation der anstehenden Lichtkurve.



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

12.02.2020 16:52
#12 RE: Supernvae als 'Standardkerzen' Antworten

https://twitter.com/betelbot/status/1227594331550339072 Das kleine Sigma steht für die Streubreite der Messungen (schwarz) und Beobachtungen (blau).

Zitat
Betelgeuse Status
@betelbot
My visual mag from last night was 1.58 (robust mean of 19 observations). That is 0.02 mag brighter than the robust mean of the 5 previous nights (n=79, 0.4σ).

3:04 nachm. · 12. Feb. 2020



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

16.02.2020 19:54
#13 RE: Supernovae als 'Standardkerzen' Antworten

Zitat
Betelgeuse Status
@betelbot
My visual mag from last night was 1.55 (robust mean of 17 observations). That is 0.04 mag brighter than the robust mean of the 5 previous nights (n=93, 1.0σ).

3:04 nachm. · 16. Feb. 2020



https://twitter.com/betelbot/status/1229043864419303424

Zitat
SPHERE public outreach
@SPHERE_outreach
SPHERE resolves the changing surface of the red giant Betelgeuse while it is dimming. At the same time thermal Infrared images obtained with VISIR support the hypothesis that large amount of dust is responsible for the dimming. Results by @Astro_MiguelM @PierreKervella



https://twitter.com/SPHERE_outreach/stat...755748047532033



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

22.02.2020 19:22
#14 RE: Supernovae als 'Standardkerzen' Antworten

Zitat von The Astronomers' Telegram # 13512, 22 Feb 2020
Three recent observations made at Wasatonic Observatory, carried out on 18.15 UT, 20.1 and 22.07 UT February 2020, returned V = +1.585 mag , +1.574 mag, and +1.522 mag, respectively. Photometry carried out by D. Carona on 18.2 UT February 2020 returned V = +1.589 mag. In addition, Wing TiO band and near-IR measures (and corresponding temperatures and luminosities) also reached minimum values during mid-February 2020. Photometry carried out by D. Carona (Texas A&M Univ.) on 18.2 UT February 2020 returned V = +1.589 mag. Also T. Calderwood's recent observations given on the AAVSO website (https://www.aavso.org/lcg) are: V = +1.589 mag, +1.567 mag and 1.556 mag, respectively on ~17.2, 19.2, 20.2 UT February 2020. Based on these and additional observations, Betelgeuse has definitely stopped dimming and has started to slowly brighten. Thus this "fainting" episode is over but additional photometry is needed to define the brightening phase. An ESO VLT/SPHERE IR image of Betelgeuse was secured during late 2019 December by M. Montarges et al. (2020: paper in preparation). The stunning VLT/SPHERE image shows that most of lower half of star has significantly dimmed, thus providing a spatially resolved image of the star informing about the observed dimming. (https://www.eso.org/public/news/eso2003/). At the time of the VLT/SPHERE observations, Betelgeuse's brightness was V ~ +1.3 mag.



http://www.astronomerstelegram.org/?read=13512



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

24.02.2020 00:44
#15 RE: Supernovae als 'Standardkerzen' Antworten

Zitat
Betelgeuse Status
@betelbot
Now at 40% of my usual brightness! #Betelgeuse
8:06 nachm. · 23. Feb. 2020



https://twitter.com/betelbot/status/1231656717634736130



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Ulrich Elkmann Offline




Beiträge: 8.089

02.03.2020 00:50
#16 RE: Supernovae als 'Standardkerzen' Antworten

Zitat
Betelgeuse Status
@betelbot
Now at 43% of my usual brightness! #Betelgeuse
8:07 nachm. · 1. März 2020



https://twitter.com/betelbot/status/1234193558657261574



"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire

Kallias Offline




Beiträge: 2.218

04.04.2020 11:58
#17 RE: Beteigeuze Antworten

https://twitter.com/betelbot/status/1246152032450269184

Die Helligkeitskurve der Beteigeuze ist nun offensichtlich in ein exponentielles Wachstum übergegangen. Die Gefahren von zuviel Licht (Overillumination) dürfen nicht länger bagatellisiert werden. Menschen können davon sterben. Die Regierung verschläft das Problem. Alle Fenster müssen jetzt innerhalb weniger Wochen mit lichtdichten Vorhängen ausgestattet werden, notfalls zumauern. Wir müssen uns darauf einstellen, in Zukunft nur noch mit Sofi-Brillen nach draußen zu gehen. Am besten bleiben wir zuhause. Sonnenöl mit Lichtschutzfaktor 1000 wird es erst in einigen Jahren geben, trotz intensiver Forschung. Ratschläge aus dem Internet, sich einstweilen mit Schweröl zu behelfen, sind unverantwortlich. Panikmache ist allerdings nicht angebracht. Die Beteigeuze-Krise hat auch Vorteile, besonders für die Umwelt, da Straßenlampen nicht mehr gebraucht werden. Anleger sollten jetzt Aktien von Photovoltaik-Herstellern kaufen.

 Sprung  



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