from an undefined
create (a place)
— Viorica Hrincu
Finding a plain-text parsable definition of the asterisms proved impossible. So I created my own.
All the constellation shapes were derived by manually examining the IAU map and cross-referencing the stars to the Yale Catalogue of Bright Stars.
The list of IAU constellation shapes in the file linked to above conveniently includes the J2000 right ascention and declination for each stars in the pair, along with their HR index, magnitude, Greek letter designation and name. See the file header for all the details.
For example, Cassiopeia's familiar "W" appears as 4 lines that indicate the connections between HR stars 21-168-264-403-542.
Cas 21 2.294583 59.149722 2.27 bet Caph|bet Cas|11 Cas 168 10.127083 56.537222 2.23 alf Schedar|alf Cas|18 Cas Cas 168 10.127083 56.537222 2.23 alf Schedar|alf Cas|18 Cas 264 14.177083 60.716667 2.47 gam BU 499A|BU 1028|gam Cas|27 Cas Cas 264 14.177083 60.716667 2.47 gam BU 499A|BU 1028|gam Cas|27 Cas 403 21.454167 60.235278 2.68 del Ruchbah|BUP 19A|del Cas|37 Cas Cas 403 21.454167 60.235278 2.68 del Ruchbah|BUP 19A|del Cas|37 Cas 542 28.598750 63.670000 3.38 eps Segin|eps Cas|45 Cas
The names are obtained from IAU Catalog of Star Names (IAU-CSN) and Simbad's name fields "NAME", "*" and "**", in that order. You can conveniently browse the Simbad database by any star identifier. For example, for Sirius the URL is http://simbad.u-strasbg.fr/simbad/sim-id?Ident=sirius.
Please report any errors to me.
The shapes of all the constellations and the stars that define the asterisms shown in the image below. I also include all the 110 Messier objects with common names in this map (hollow circles).
The map also shows the galactic equator and the ecliptic. The vernal equinox, summer solstice, autumn equinox and winter solstice occur along the ecliptic at right ascension 0/360 (Pices), 270 (Sagittarius), 180 (Vigo) and 90 (Gemini/Taurus).
Whole-sky star charts are traditionally drawn with 360 right ascention on the left in decreasing order towards 0 on the right.
If you're interested in more astronomical resources, check out my Universe Superclusters and Voids resource page.
I've also created detailed charts that include all the 9,110 stars in the Yale Catalogue of Bright Stars. These are labeled by their Greek designation with the constellation as well as with their IAU name.
The maps also show all 110 Messier objects, labeled by their index and, where available, a common name. All the labels in these maps have been lovingly adjusted manually to avoid ambiguity and overlap. Available are blue, black and white background versions.
We focus on the important distinction between confidence intervals, typically used to express uncertainty of a sampling statistic such as the mean and, prediction and tolerance intervals, used to make statements about the next value to be drawn from the population.
Confidence intervals provide coverage of a single point—the population mean—with the assurance that the probability of non-coverage is some acceptable value (e.g. 0.05). On the other hand, prediction and tolerance intervals both give information about typical values from the population and the percentage of the population expected to be in the interval. For example, a tolerance interval can be configured to tell us what fraction of sampled values (e.g. 95%) will fall into an interval some fraction of the time (e.g. 95%).
Altman, N. & Krzywinski, M. (2018) Points of significance: Predicting with confidence and tolerance Nature Methods 15:843–844.
Krzywinski, M. & Altman, N. (2013) Points of significance: Importance of being uncertain. Nature Methods 10:809–810.
A 4-day introductory course on genome data parsing and visualization using Circos. Prepared for the Bioinformatics and Genome Analysis course in Institut Pasteur Tunis, Tunis, Tunisia.
Data visualization should be informative and, where possible, tasty.
Stefan Reuscher from Bioscience and Biotechnology Center at Nagoya University celebrates a publication with a Circos cake.
The cake shows an overview of a de-novo assembled genome of a wild rice species Oryza longistaminata.
The presence of constraints in experiments, such as sample size restrictions, awkward blocking or disallowed treatment combinations may make using classical designs very difficult or impossible.
Optimal design is a powerful, general purpose alternative for high quality, statistically grounded designs under nonstandard conditions.
We discuss two types of optimal designs (D-optimal and I-optimal) and show how it can be applied to a scenario with sample size and blocking constraints.
Smucker, B., Krzywinski, M. & Altman, N. (2018) Points of significance: Optimal experimental design Nature Methods 15:599–600.
Krzywinski, M., Altman, N. (2014) Points of significance: Two factor designs. Nature Methods 11:1187–1188.
Krzywinski, M. & Altman, N. (2014) Points of significance: Analysis of variance (ANOVA) and blocking. Nature Methods 11:699–700.
Krzywinski, M. & Altman, N. (2014) Points of significance: Designing comparative experiments. Nature Methods 11:597–598.
An illustration of the Tree of Life, showing some of the key branches.
The tree is drawn as a DNA double helix, with bases colored to encode ribosomal RNA genes from various organisms on the tree.
All living things on earth descended from a single organism called LUCA (last universal common ancestor) and inherited LUCA’s genetic code for basic biological functions, such as translating DNA and creating proteins. Constant genetic mutations shuffled and altered this inheritance and added new genetic material—a process that created the diversity of life we see today. The “tree of life” organizes all organisms based on the extent of shuffling and alteration between them. The full tree has millions of branches and every living organism has its own place at one of the leaves in the tree. The simplified tree shown here depicts all three kingdoms of life: bacteria, archaebacteria and eukaryota. For some organisms a grey bar shows when they first appeared in the tree in millions of years (Ma). The double helix winding around the tree encodes highly conserved ribosomal RNA genes from various organisms.
Johnson, H.L. (2018) The Whole Earth Cataloguer, Sactown, Jun/Jul, p. 89
An article about keyboard layouts and the history and persistence of QWERTY.
McDonald, T. (2018) Why we can't give up this odd way of typing, BBC, 25 May 2018.