for students writing their first paper (and others) Rev. December, 2007

• 1. The whole point of an article is to tell a story. What is the story you want to tell? Your pictures and graphs help in telling the story, but each one needs to be thoroughly introduced as if you were giving a lecture to a group of students. Revisit the abstract after you think you are done. Does it sum up the story and communicate the big picture of what this means to science (or to humanity) as a whole?
• 2. Figures:
  • A. Each figure needs a descriptive caption that not only introduces the axes and symbols used, but summarizes what the figure is intended to communicate.
  • B. When preparing for publication, use a line weight of 2 or greater to make thick, dark, bold lines and symbols.
  • C. Every figure needs a legend to explain symbols and lines or other annotations, even if these are also explained in the caption. It makes your figures much easier to digest for newcomers.
  • D. Figures are always introduced in the text in order. I.e., never talk about Figure 3 before Figure 2.
  • E. Always use different line types and point types in figures so that you don't rely on color. Most people will read your figure in B&W so make it legible that way.
• 3. Tables
  • A. Use proper number of significant figures.
  • B. Include uncertainties on all measurements
  • C. Use table footnotes to explain your table headings

• 1. Active/Passive voice
  • Use the active voice wherever possible, Subject followed by verb. I.e., "Figure 4 shows the correlation between amplitude and mass" is superior to "A correlation between amplitude and mass can be seen in Figure 4". Reserve use of the passive voice for things which are not your fault, i.e., "The night was not photometric so the data were not flux calibrated".
  • Other examples of active/passive preference: Say "Table 1 lists the magnitudes of each star" rather than "The magnitudes of each star can be found in Table 1."
  • Active sentences are punchier and more fun to read than passive sentences. Try
    • "Figure 1 reveals the differences between Population 1 and Population II".
    • "Figure 2 displays the 8.0 and 10.0 micron images of the cluster."
    • "Figure 3 reveals that stars without disks are preferentially more blue than stars with disks."
    • "Figure 4 shows a greyscale V-band image of NGC 4565." etc...
• 2. Use of We/I.
  • It is increasingly acceptable to use the second person, or (less commonly) even first person pronouns to describe the activity of the authors.
    • "We obtained data on the night of 2004 February 30."
    • "We cross correlated the Hubble Guide Star catalog objects with the 2MASS catalog."
  • Limited, appropriate use of we/I is encouraged.
• 3. Sentence structure
  • A. Eschew gerund phrases that open a sentence. E.g., "Looking at Figure 1, the star lies on the periphery of the cloud". This is poor syntax because it means something colloquial like "When I look at Figure 1 I see that ....". Replace it with, "Figure 1 shows that the star lies on the periphery of the cloud".
  • B. Avoid leading prepositional phrases. They are often colloquial and informal. "To flux calibrate the photometry, we observed five standard stars." Instead use, "We observed five standard stars to flux calibrate the photometry."
  • C. Make good use of simple sentences. They are punchy and lively and easy to read. Where possible, combine related ideas in adjacent sentences to save space and form a single sentence.
  • D. Commas always follow the "and" or "but" which joins independent clauses in a compound sentence. "Galaxies with active central black holes often exhibit jets, but galaxies without active nuclei should not show them." Commas do not join trailing dependent clauses to an independent clause. WRONG: Stars with disks have infrared excesses, and have submillimeter excesses. OK: Stars with disks have infrared excesses, and they have submillimeter excesses.
  • E. Commas always follow leading prepositional phrases. "Although the weather was partly cloudy, we obtained several short exposures of Beta Pictoris."

• 1. Read, sentence by sentence, looking for
  • A. Is each sentence grammatically correct? Is there singular/plural agreement between the subject and the verb? (Note: "spectrum" is the singular of the plural "spectra". "Data" is the plural of the singular "datum".)
  • B. Is the sentence unnecessarily long and complex? Can it be shortened into two simpler, punchier sentences? Make a revision through your text, replacing boring words with exciting words, where possible.
  • C. Can two simple ideas be synthesized into a single sentence to save space?
  • D. Is every term or concept introduced with a sufficient level of detail for your audience, especially words that carry technical meanings?
• 2. Read, paragraph by paragraph, looking for
  • A. Does the lead sentence of the paragraph clearly convey the main idea of the paragraph?
  • B. Are the topics covered in a paragraph sufficiently united to warrant being one paragraph, or should the paragraph be split up?
  • C. Are neighboring paragraphs (especially short ones) sufficiently related that they can be joined into a single paragraph?
• 3. Read, section by section, looking for
  • A. Is the flow of ideas continuous and logical? Is there a more logical ordering of the sections of the paper which would facilitate reading by a novice in the field?
  • B. Can long blocks of text be broken into logically titled subsections to facilitate reading and organization?

• 1. Avoid overuse of the possessive pronouns: It's ok to say "our data" or "our models" or "our sample" but inappropriate to say "our galaxies" or "our stars" since they really don't belong to us.
• 2. Avoid overuse of distracting and qualifying words. E.g., "Figure 5 appears to show that ...." -> "Figure 5 shows that ..." "Thus, the data are inconsistent with the model" -> "The data are inconsistent with the model." Reserve words like "Thus" or "Therefore" only for rare situations where a real logical conclusion is being imposed by the preceding sentences.
• 3. Adverbs that end in "ly" are not hyphenated. E.g., "photometrically calibrated" NOT "photometrically-calibrated".
• 4. e.g., and i.e., are always followed by commas because they are abbreviations for "for example" and "in other words".
• 5. Avoid acronyms because they can make reading a real slog. Only use "very famous" acronyms that everyone will immediately know, e.g. CMB
• 6. Enclose all variable names in $ $ in TeX. E.g., "The factor, $X$, denotes the conversion factor of $CO$ to $H_2$."
• 7. Capitalize "Figure 1", "Table 3", etc.
• 8. In Tex and LeTeX (and to a printer) there is an important difference between "-" and "--" and "---". The first is called a hyphen and is used to separate compound works like "ever-lasting". The second is called an n-dash and is used to illustrate ranges: "The range of possible stellar masses is 3--4 solar masses." The last is called an m-dash and is used when indicates a sudden break in thought--- parenthetical statement like this one---or an open range (such as "John Doe, 1987---").
• 10. Use a spell checker!
• 11. Read ApJ & AJ instructions for authors.
• 12. Read and study Online writing style guides
• 13. Read and study read about the use of hyphens and dashes