Monthly Archives: March 2016

My son and the “Story of the Planets”

I spend a lot of time with my son, Luke. He turned 3 last January and, after the terrible “terrible twos” phase he is a very different and charming little person now. He has been always obsessed with letters and numbers. Indeed he does not only know his ABC’s in Spanish and in English but he also identifies Greek letters (*). He has been doing these for around a year (the Greeks letters since Christmas). Lately he’s even writing letters by himself in his (several) blackboards or in the sand at the beach. And with numbers he’s always counting everything: pieces of food, toys, steps… I think he is starting to understand what additions and subtractions are. Yes, I do have a lot of fun playing with him (not that much when it is 10pm and he refuses to go to bed, but, ey, we’re Spanish, going to bed at 10pm is not bad seen in our native country… it must be on the genes…).

Of course I also talk about Astronomy to him. Using “glowing in the dark stars” we drew constellations in his bedroom. He now knows what “the Southern Cross“, “Orion” and “Scorpius” are, even the Pleiades (not a constellation, just a a star cluster or an asterism). A couple of weeks ago I got a small book about Astronomy for him. In only 50 pages it compiles planets, constellations, star clusters, nebulae and galaxies. It is not a book for a 3 years old, but I wanted to show him the photos of the planets. And he was fascinated about that!

Since then, every night, I have to take him to bed (as said, that usually happens later than 10pm) and read him “the story of the planets“. The book has too much text, so I just tell him funny things and curiosities about the planets. He loves it!

Yesterday, as every Sunday, it was he and me alone (and Luci, our little dog), as mum works on the weekends. It was another sunny day in Sydney, and I really wanted to go to the beach (some friends were actually meeting in Manly). But Luke didn’t want to go anywhere, he wanted to stay at home playing with the many toys and books he has. Eventually he went to his bedroom and came back to the living room bringing the book with “the story of the planets”. He wanted to play with it. Then I asked him: “do you want we make planets to put in your bedroom?“. A second after that he was just jumping and laughing, excited as crazy, “¡sí, sí, sí, papi!”.

And that was it, we took white paper and color pen markers and, following the images of the planets in the book, made our own “Solar System”:

The planets that my son & me make yesteday

The planets that my son & me make yesterday. Sizes are NOT in scale.

Mercury was easy. For Venus and the Earth we used a glass and just painted with oranges-brown (Venus) or green-blue (Earth) colors. Mars was also easy just painting using red colors. I tried to add the details of the polar caps (the same that the clouds on the Earth) but our white crayon didn’t work well with the pen markers. Jupiter was fun, we used the empty box of a large yogurt (actually, that is where he has his pen markers, pencils and crayons) and just did stripes in orange colors over a yellow background to follow the Jovian bands. We added the detail of the Giant Red Spot with a red pen maker. We used a similar trick to draw Saturn (of course, this is Luke’s favorite planet) and then added the rings using a new piece of white A4 paper. Saturn’s rings were indeed the most difficult part to get, and I’m still not convinced of the result. In reality the are not that dark, and its shape is funny. We then just finished with the ice giants Uranus (pale blue with not many details on the disk) and Neptune (green-blue including some details in the clouds, and the “Great Dark Spot”).

Once this was done, Luke was really happy with “his planets”, and was counting them and naming them all the day. But I waited to the night to put them on his bedroom.

My son's bedroom wall with stars and planets

My son’s bedroom wall with stars and planets (and the X-Wing, of course).

At 9pm I said “let’s go to put your planets in your bedroom, and I’ll read you the story of the planets” and he went happily to bed. We used bluetag to do this. The result is really nice, and he is so exciting about all of this!

And, yes, we didn’t make Pluto because it is not a planet. But, don’t worry, he already knows there are other things in the Solar System: the Sun, asteroids, comets and five dwarf planets (Ceres, Pluto, Eris, Haumea and Makemake), as well as many planets have also moons! We’ll eventually make many of them.

I’ll need a bigger wall…

(*) Why teaching Luke Greek letters? Well, stars are named with Greek letters (e.g., Alpha Centauri) , and I remember it took me a while to memorize that when I was a teenager. But, more importantly, Physics and Math equations are written with Greek letters. And I write many of these in his blackboards. Yes, I know, he is little, but he is absorbing everything and I’m sure it will not hurt for him to be familiar to, let say, the Newton Equations, although some times I’ve written Einstein General Relativity, Maxwell’s Equations, or Schrodinger Equation. Luke does not pay too much attention to all of that, but he loves reading the Euler Equation “e i π plus 1 equal zero”.

Starburst spiral galaxy NGC 3310 with Gemini North

Last Tuesday 1st of March the famous NASA webpage Astronomy Picture of the Day (APOD) released a very nice image of the galaxy NGC 3310 obtained with the 8.2m Gemini North Telescope in Hawaii (U.S.A.).

Nice image of the starburst spiral galaxy NGC 3310 in the Ursa Major obtained with the 8.2m Gemini North Telescope in Hawaii (U.S.A.). This image was obtained for the “Cosmic Poll” contest organized by the International Telescopes Support Office at the Australian Astronomical Observatory (AAO) and appeared as APOD on 1st March 2016. Colours codify the light received in blue (B, blue) and red (R, green) filters, plus the emission of the ionized gas (Hα filter) coded in red.AAO ITSO Office, Gemini Obs./AURA & T. A. Rector (U. Alaska Anchorage).

NGC 3310 lies at a distance of around 50 million years from us, within stars of the Northern constellation of the Ursa Mayor (meaning we cannot see it here from Australia, well, it has a maximum elevation of ~5 degrees from Siding Spring Observatory). The spiral structure in NGC 3310 looks like what we expect for our own Milky Way galaxy, with plenty of star-forming regions (in red-pink colours tracing the Hα emission). However in the case of NGC 3310, the star-formation activity seems to be more extreme.

It seems that NGC 3310 started experiencing an interaction with a dwarf galaxy around 100 million years ago. This interaction has triggered a very strong star-formation event (that is why NGC 3310 is defined as a starburst galaxy), and has “broken” the external areas of the galaxy as consequence of the intense tidal forces. In the image, all regions showing red-pink colours (tracing Hα emission) are nebulae. These regions are found almost everywhere within NGC 3310, sometimes even forming some peculiar alignments of red-pink-ish regions as that “ray” that goes from the centre of the galaxy till the upper left corner. It is interesting to note that, although the interaction with the dwarf galaxy happened ~100 million years ago, the fact of finding this large amount of Hα emission informs that the star-formation activity is still important today. The colliding dwarf galaxy was probably engulfed by NGC 3310, its remaining debris could be that diffuse arc-like structure we observed in the outskirts of the galaxy in the upper part of the image.

These are the kind of objects (starburst galaxies) and the kind of features (enhanced Hα activity, tidal distortions of the stellar component of the galaxy, tails, rays…) I studied in a sample of dwarf galaxies for my PhD Thesis (I still have to tell all of that here…).

Beside tracing the nebular (Hα) emission, the image also allows to distinguish that the majority of the stars in NGC 3310 have blue colours, even in its external areas. Again, this fact informs that the dominant stellar populations in this galaxy are relatively young, as only young stars emit a lot of light in blue and ultraviolet colours.

Although it was not said in the APOD I would like to remark that the idea of observing this galaxy in the 8.2m Gemini North Telescope came from the International Telescopes Support Office at the Australian Astronomical Observatory (AAO). In particular, mi colleagues Elaina Hyde, Richard McDermid, Caroline Foster-Guanzon and Stuart Ryder (AAO) organized a very interesting outreach initiative, the Cosmic Poll, asking the people to emit a vote for which kind of object would they like to be observed at the 8.2m Gemini Telescope. The winning entry was “an individual galaxy”, and later they decided to observe NGC 3310. Furthermore they organised an on-line event,a live-stream with the Gemini North Telescope (is available on YouTube) explaining how the telescope works and giving details of the observatory. The Gemini Observatory website also included this in its blog. After processing and cleaning the images, the final result is that you see in APOD.

I couldn’t help myself, though, and decided to play a bit with the colours, levels, contrast and lights of the image to try to get an enhanced image of this very nice object. In my opinion, the central part of the galaxy is a bit too bright (it should be, of course, the real difference in brightness between the central part of NGC 3310 and the diffuse stellar streams in its outskirts is several orders of magnitude, but for illustration purposes I have found that it is a good idea to minimize that) and the outskirts of the galaxy are not that easy to see. So here it goes my enhanced image of NGC 3310 with Gemini North:

Comparison between the image of the starburst spiral galaxy NGC 3310 obtained by the 8.2m Gemini North Telescope and published in APOD on 1st March 2016 (left) and the same image enhanced by myself (right). Credit: AAO ITSO Office, Gemini Obs./AURA & T. A. Rector (U. Alaska Anchorage), Enhancement: Ángel R. López-Sánchez (AAO/MQ)

What do you think? What image do you like more?