Preflight

The Preflight section of Voyages is designed to provide SDSS specific information about key concepts in astronomy. They can be used as reference material, homework assignments before beginning another activity or the starting place for a class discussion. They are informational. Unlike the rest of the activities you will find in Voyages, they are not inquiry-based. Below we have provided charts summarizing each Preflight reading, which explain key vocabulary and thoughts about how each might fit into a learning sequence.


RA and Dec
Driving the SDSS Telescope – Understanding Right Ascension and Declination

Summary
This Preflight training provides students with an overview of lines of right ascension and declination, how they are measured, and how the decimal degrees (specialized representation of RA and Dec in the SDSS) are calculated by computers.

Key Vocabulary

declination

right ascension

Supporting Vocabulary

degrees, minutes, and seconds

hours, minutes, and seconds

decimal degrees

celestial north pole

celestial south pole

Comments
This activity is a useful resource for reviewing RA and Dec in the form of decimal degrees used by the SDSS.

If your students have no prior experience with RA and Dec, consider Launch – My Special Place in the Database or Launch – Constellations as part of the experience.


Structured Query Language – SQL

Locating Objects in a Database

Summary
In this Preflight training, students are introduced to the fact that massive amounts of data can be stored on computers in an organized manner. This data can be searched in variety of ways using a simple language called SQL (structured query language). The activity uses the first two lines of code – the Select and From lines – to demonstrate how a query functions.

Key Vocabulary

SQL

database

query

Supporting Vocabulary

Comments
This activity is recommended if you come across the concept of querying a database but it is not part of the main lesson.

Other activities that teach SQL as part of the lesson are Launch – Galaxies and Expedition – Galaxy Color.


Preflight – Asteroids

Summary
Asteroids are not targets of the SDSS. During the long exposures times used to capture faint galaxies and quasars, many asteroids are recorded as colored streaks or a series of colored dots on the image. In this Preflight, students learn how to identify asteroids in SDSS images and how the engineering goals of the telescope (target faint objects) result in clear images of stars and galaxies and streaked images of asteroids.

Key Vocabulary

asteroid

filter

Supporting Vocabulary

image

SDSS camera

planets

stars

comet

meteor

Comments
Although the aim of this activity is to help students identify asteroids and moving objects in SDSS images, you can use it as a starting place for a discussion about how the SDSS telescope was

designed by engineers to meet a particular goal. The engineering goal of the SDSS camera and telescope is to capture images and spectra of very faint and distant objects over large portions of the sky.

If you are interested in continuing to explore the nature of the data captured by the SDSS, Launch – What is SkyServer provides the details.

Preflight – Artifacts provides more examples of objects captured by the SDSS telescope and camera that were not the intended targets of the system. A discussion of the design characteristics the system would have needed to successfully image these objects would help students think about the engineering involved in scientific discoveries.


Preflight – Spectrum Graphs

Summary
This Preflight training takes a detailed look at an SDSS spectrum graph. Students are provided with information about the types of data recorded on the graphs, the units used, and how to interpret the information.

 Key Vocabulary

spectrum graph

X and Y axes

continuum

emission line

absorption line

blackbody curve

Supporting Vocabulary

nanometer

angstrom

erg

flux

ultraviolet

infrared

Comments
The information on the page is very dense; a great number of topics related to spectra are covered. As in all Preflight trainings, students are being told the information that is known about spectra. If you would like your students to uncover and interpret these patterns for themselves, we recommend Launch – Stellar Spectra for exploring the nature of the continuum curve, Launch – Stars as Blackbodies for interpreting temperature, and Launch – Redshift for a closer look at absorption and emission lines.


Preflight Redshift

Summary
Preflight – Redshift covers the very basics about what a redshift is and a generalized description of how it is measured on an SDSS spectrum graph.

Key Vocabulary

redshift

Doppler effect

Supporting Vocabulary

spectrum

spectrum graph

spectral lines

z value

Comments
For more about redshift, Launch – Redshift provides a detailed investigation of how spectral lines are identified and used to calculate redshift.


Preflight – Filters

Summary
Using an analogy, Preflight – Filters explains the function of a filter and how it does the job of blocking some colors of light. As with all Preflight trainings, information is presented in the context of the SDSS; no other filters or systems are discussed. The wavelength nature of light is introduced as it is essential to understanding the “colors” that we do not see and how filters function.

Key Vocabulary

light

filter

wavelength

color

Supporting Vocabulary

electromagnetic spectrum

electromagnetic radiation

Angstrom

camera – as separate from the

filter

Comments
This Preflight activity does not attempt to teach everything about the electromagnetic spectrum or the nature of light. There are many supporting classroom experiences that accomplish this effectively. Our aim here is to provide an understanding of light and filters within the SDSS that serves as a context for further experiences such as Launch – Star Color.


 Preflight – Magnitude

Summary
The magnitude scale in astronomy is very confusing. Preflight – Magnitude is here to provide a quick reference when students need a review or the basic overview for the first- time astronomer. This training provides the historical background for the development of the scale and numerous examples to ground this unit-less measurement to familiar objects like the moon.

Key Vocabulary

magnitude

Supporting Vocabulary

standard comparison

apparent magnitude

absolute magnitude

Comments
Try Launch – Star Color if you would like you students to uncover the nature of the magnitude scale on their own. Preflight – Magnitude is also a good review before Expeditions.


Preflight – Calculating Magnitude

Summary
This Preflight training offers a short demonstration about how magnitude (a unit-less measurement) is derived by comparing the energetic output of the star to that of the star Vega.

Key Vocabulary

radiant flux

magnitude

logarithm

Supporting Vocabulary

Comments
Some student questions require a more in- depth understanding of the nature of magnitude measurements. Magnitude itself is a useful demonstration of the different base operations of the log scale.


Preflight – The SDSS Telescope

Summary
The SDSS telescope has many unique design features as well as much in common with other large research telescopes. This Preflight training provides background information about the location, design, and dimensions of the telescope.

Key Vocabulary

telescope

Supporting Vocabulary

primary mirror

secondary mirror

Comments
This Preflight could be used along with Preflight – SDSS Instruments and Preflight – Types of Data to explore how the science goals of the survey were met in the engineering design process. Questions such as – What features and functions did engineers need to design into the SDSS telescope/camera system to capture the different types of SDSS data? – are accessible through these readings.

A video introduction to this activity in Spanish and American Sign language is available HERE. Voyages is eager for feedback about how teachers are using these videos at voyage@sdss.org


Preflight – The SDSS Telescope Instruments

Summary
This Preflight training reviews the function of a telescope and introduces the idea that a way to record the information (light) is necessary if your goal is to share images and data. The CCD camera and spectrograph are the two main instruments that work with the SDSS telescope to do those jobs. The reading explains how each instrument is designed to produce different outcomes.

Key Vocabulary

CCD camera

spectrograph

CCD chip

pixel

telescope

Supporting Vocabulary

prism

wavelength

fiber optic cable

SDSS plate

Angstrom

Comments
Video resources:
Plugging the Plates
SDSS at Night

We recommend that no matter what activity you do with students, you always reinforce the telescope/camera or telescope/CCD as a system that works together to achieve a goal. This Preflight is always available as a reminder. Students can reference this section anytime they are unclear about the role of each instrument in gathering data.


Preflight – Types of Data

Summary

This Preflight training emphasizes the two primary data types recorded by the SDSS, photometric and spectroscopic. The reading shows how each type of data is accessed through the Navigate tool in SkyServer and provides an overview of how to locate more detailed descriptions through the QuickLook tool.

Key Vocabulary

photometric data

spectroscopic data

Supporting Vocabulary

 Comments
Although the telescope/camera or telescope/spectrograph system is mentioned in this Preflight, the emphasis here is on the data output and where the data are located.