Today I’ve been interviewed in ABC Science about the “Supermoon” that we can enjoy tonight, 7th May 2020. For this we have used some of the images of the moon that my son and me have been taking during the last year.
I want to thank Genelle Weule for the excellent questions and for her great interest about astronomy and astrophotography.
Posted in Amateur, Astrophotography, Moon, Observation, Outreach
Tagged 2020, Amateur Astronomy, astronomy, astrophotography, Luke, moon, Outreach
Comet C/2020 F8 (SWAN), Sydney, May the 4th, 2020, 5:15am
Image combining 10 x 2min exposures using an Optolong L-Pro filter, Skywatcher BD80, focal reducer Orion x0.8, ZWO ASI178MC. Mount Skywatcher AZ-EQ6 Pro mount, camera ZWO ASI120MM for guiding and ASIair for controlling everything.
Individual frames dark subtracted with Siril software, then I did the alignment on the comet manually in Photoshop (that is why stars are moved and blurry, as stacked with median), where I also played with the color/brightness/contrast.
The top image is the resulting color image, the bottom image is the greyscale image increasing the contrast to increase the visibility of the tail and the faintest features.
Full resolution image in my Flickr.
A Twitter thread compiling some extra information about the imaging process in here.
Credit: Ángel R. López-Sánchez (AAO-MQ).
May 4, 2020 in Amateur, Astrophotography, Comets
Tagged 2020, astronomy, astrophotography, Comet
Test image of M 8 (The Lagoon Nebula) from my backyard, 15 km North from Sydney’s city center, on 21st Aug 2019.
That was my first attempt to get the new equipment working. I was testing the Skywatcher AZ-EQ6 mount and the ZWO ASI120MM (guiding) and ZWO ASI178MC (main camera) with the ASIair. But I had plenty of problems to get the guiding working as the mount was not properly aligned to the South Celestial Pole (over Sydney, very difficult to see the faint stars using the polar scope of the mount). I had to use the drift method. After that, getting the ASIair properly guiding was hard as I couldn’t find any easy manual and never used PHD for guiding before.
This image combines 25 (of a series of 60) good 180s frames using the ZWO 183MC and my Skywatcher Black Diamond 80 (F=600mm, f/7.5. No darks, flats, biases or light pollution filter was used for this.
Later it was also tricky for me to play with the raw data: I have never used a color camera producing .FITS files before! It took me some time to get a good free(*) software for it and I found Siril. But the “bayer” decomposition didn’t work well with the ZWO cameras and my images had very weird colours.
In March 2020 I learnt a couple of extra things, including changing the bayer matrix from RGGB to GBRG for ZWO cameras and… bingo! So here it is the test image I got that night more than half a year ago! And still testing the equipment!
Ah, yes, stretching, colour contrast, saturation, levels, and luminosity with Photoshop.
Full resolution image in my Flickr.
Credit: Ángel R. López-Sánchez (AAO-MQ).
(*) Don’t get me wrong… I’ll get PixInsight eventually, when I get everything working well.
Although we are “enjoying” the Christmas break, today I’ve been contacted (thanks to Rami Mandow @CosmicRami) by Kelsie Iorio, an ABC News Digital journalist who was preparing an article about the situation of the red supergiant Betelgeuse.
The article published in ABC News, entitled “Is Betelgeuse, the red giant star in the constellation Orion, going to explode?“, can be found in this link. It includes comments from Rami Mandow, Associate Professor Michael Brown from Monash University’s School of Physics and Astronomy and myself, with some other tweets from several astrophysicists who are talking about the “mysterious dimming of Betelgeuse“.
The red supergiant star Betelgeuse in Orion was the very first star after the Sun we got a direct image of its surface. That is because it is a huge star: if it were where the Sun is its outer layers will reach the orbit of Jupiter! This image was taken with the Hubble Space Telescope in 1995. More info in the APOD (Astronomy Picture of the Day) on April 19th, 1998. Credit: A. Dupree (CfA), R. Gilliland (STScI), FOC, HST, NASA.
But I want to share with you my full interview here, and keep it for my records, so here it goes.
Interviewer: Kelsie Iorio (ABC News Digital )
Interviewee: Ángel R. López-Sánchez (AAO-MQ)
Q: For those who don’t know, what is Betelgeuse and what is it doing at the moment that’s out of the ordinary?
Betelgeuse is a bright star in the famous constellation of Orion the Hunter. It is a red supergiant star, meaning that it is star that is much more massive than our Sun (10 – 15 times) and that is already in the latest stages of its live. The star will eventually explode as a (type II) supernova. We astrophysicists know this will happen “soon”, but “soon” in Astronomy means 100 thousands years or perhaps even more.
During the last month observers worldwide have measured a dimming in the brightness of Betelgeuse.
This is actually completely ordinary, as it is well known and documented that Betelgeuse is a variable star (that means that it’s periodically changing its brightness).
Social media has again played a role here with the “hype” of the brightness of Betelgeuse: it is a normal situation that is happening at the moment and we can explain the dimming of Betelgeuse in many ways (a small shrinking of its huge size, solar spots, magnetic activity, a combination of factors) without the need of thinking that is going to explode now.
But people have been talking about that and many of them would love to see Betelgeuse explode! (I do not).
Q: Why is the astronomy world so excited about what’s happening?
If Betelgeuse really explodes as a supernova this would be a great opportunity for use to study how massive stars explode and get a better understanding of stellar evolution and stellar interiors. It will create a point-like object as bright as the Moon that would be visible even during the day, that will be fading during months till disappear.
However I must insist: the dimming of the brightness is the typical behaviour of the star. It is periodically changing its brightness and it has had this “low” brightness in the past. Even Aboriginal Australian knew this star changed brightness!
Q: Can we see Betelgeuse from Australia? For people who haven’t seen it or don’t know how to look for it, what does it look like from earth?
Of course! This is a star located very close to the celestial equator, meaning it can be seen essentially from everywhere (just not from the very same South Pole and around). Right now it is clearly visible to the North-East at the beginning of the night. The constellation of Orion is one of the most famous constellations of the sky and can be very easily recognised even by non-experts. Just use a stellar map (there are plenty free in internet, I recommend http://skymaps.com, and also plenty of apps) and you’ll see it. Despite it has noticeable dimmed in the last month, Betelgeuse still is one of the brightests stars in the night sky.
As any other star Betelgeuse is just a point of light, even when using a powerful telescope: stars are very, very, very far away from us to see them like a little disk. Betelgeuse is at a distance of around 700 light years.
Q: What do you think will happen to Betelgeuse next? Is it likely to explode?
No, it is very unlikely we see it exploding. The latest astrophysical research conducted about Betelgeuse clearly shows that it should still have a life of around 100 thousand years. Again, that is almost NOTHING in the cosmic scale, but a lot for us.
As it has done plenty of times in the past, Betelgeuse will eventually gain brightness again and all will be back to usual, continuing being sometimes a bit brighter sometimes a bit dimmer during the rest of all our own lifetimes.
Q: Is what’s happening with Betelgeuse a rare event?
No, it is not a rare event.
There are PLENTY of variable stars in the sky. A nice example is the star Mira in the constellation of Cetus (the Whale). This star sometimes can be easily seen with the naked eye and sometimes it is imposible to see, needing binoculars or telescopes to detect it. And it is not going to explode as supernova!
Q: Do you believe it’s important for the wider public to have a basic knowledge of astronomy and understand what’s happening in situations like this? Why?
I think it is important because everyone loves Astronomy but nowadays it is very easy to be confused because of the mixed bag of content found in social media and the internet.
I could tell the story about why supermoon are NOT a thing, but that is for another time (or read it here: https://angelrls.wordpress.com/2016/11/11/supermoons/)
Article in ABC News: “Is Betelgeuse, the red giant star in the constellation Orion, going to explode?“, Kelsie Iorio, 28th December 2020.
Posted in Astrophysics, Massive Stars, Optical, Outreach, Stars, Supernovae, Wavelengths
Tagged 2019, astronomy, Betelgeuse, massive stars, Outreach, Science Communication
Today I’ve done something I would have not expected to do in Australia: I gave a talk in Spanish! In my 12+ years living and working in this country I can only think in 2 occasions I did something like this: in 2009 I gave an informal talk about my research for the staff at the Spanish Embassy in Canberra, and in 2011 I gave an invited science seminar to researchers of the Spanish polar research vessel “BIO Hespérides” when it was docked at Sydney’s Harbour.
Today I’ve been with the very enthusiastic young students of ALCE “Australia Lengua y Cultura Española” as part of the science communication activities that we do at SRAP-IEAP (Spanish Researchers in Australia-Pacific, Investigadores Españoles en Australia-Pacífico). It was in the Willoughby classroom (Sydney), thanks to the invitation of the ALCE Director, Raquel Pardo. I was talking about the Solar System (in perspective, not only the Sun and the planets) plus I answered many of the questions about stars, galaxies, black holes and the universe they had.
1/3 of the ALCE students after my talk at the ALCE Willoughby classroom on 27th Nov 2019. They were so excited about Astronomy we didn’t take a single photo during the event! It was at the very end, when 2/3 of them have already gone and I was starting to pack up, when we realised we didn’t have taken any photo! And, yes, my son is there (it is easy to see who he is). Credit: Ángel R. López-Sánchez.
As an extra I had a very special helper: my very own son, who, you know, loves the planets and the moon. It was a great experience for him as he had to say all of it in Spanish in front of other people. Plus, that was awesome, he was actually showing in the slides what I was talking about… I was very happy about it as we didn’t rehearsal anything!
A/Prof. Ángel R. López-Sánchez 