• 2010 nasa special
    a total eclipse of the Sun is visible from within a narrow corridor that traverses Earth's southern Hemisphere. The path of the Moon's umbral shadow crosses the South Pacific Ocean where it makes no landfall except for Mangaia (Cook Islands) and Easter Island (Isla de Pascua).

EVE: Measuring the Sun's Hidden Variability


Still from video detailing SDO's EVE instrument Credit: NASA/Goddard Conceptual Image Lab
› Watch video

The extreme ultraviolet (EUV) sun imaged by SOHO over one complete solar cycle The extreme ultraviolet (EUV) sun imaged by the Solar and Heliospheric Observatory (SOHO) over one complete solar cycle. The sun changes more at EUV wavelengths than it does in any other part of the electromagnetic spectrum. Credit: NASA/SOHO
› Larger image

EVE with its sensors labeled: MEGS-A and -B, ESP, and SAMS.The Extreme Ultraviolet Variability Experiment (EVE) has four primary sensors. MEGS-A and -B are the Multiple UV Grating Spectrographs; ESP is the EUV Spectrophotometer; SAMS is the Solar Aspect Monitor. Credit: NASA
› Larger image Every 11 years, the sun undergoes a furious upheaval. Dark sunspots burst forth from beneath the sun's surface. Explosions as powerful as a billion atomic bombs spark intense flares of high-energy radiation. Clouds of gas big enough to swallow planets break away and billow into space. It's a flamboyant display of stellar power.

So why can't we see any of it?

Almost none of the drama of Solar Maximum is visible to the human eye. Look at the sun in the noontime sky and—ho-hum—it's the same old bland ball of light.

"The problem is, human eyes are tuned to the wrong wavelength," explains Tom Woods, a solar physicist at the University of Colorado in Boulder. "If you want to get a good look at solar activity, you need to look in the EUV."

EUV is short for "extreme ultraviolet," a high-energy form of ultraviolet radiation with wavelengths between 1 and 120 nanometers. EUV photons are much more energetic and dangerous than the ordinary UV rays that cause sunburns. Fortunately for humans, Earth's atmosphere blocks solar EUV; otherwise a day at the beach could be fatal.

When the sun is active, solar EUV emissions can rise and fall by factors of hundreds to thousands in just a matter of minutes. These surges heat Earth's upper atmosphere, puffing it up and increasing the air friction, or "drag," on satellites. EUV photons also break apart atoms and molecules, creating a layer of ions in the upper atmosphere that can severely disturb radio signals.

To monitor these energetic photons, NASA is going to launch a sensor named "EVE," short for EUV Variability Experiment, onboard the Solar Dynamics Observatory this winter.

"EVE gives us the highest time resolution and the highest spectral resolution that we've ever had for measuring the sun, and we'll have it 24/7," says Woods, the lead scientist for EVE. "This is a huge improvement over past missions."

Although EVE is designed to study solar activity, its first order of business is to study solar inactivity. SDO is going to launch during the deepest solar minimum in almost 100 years. Sunspots, flares and CMEs are at a low ebb. That's okay with Woods. He considers solar minimum just as interesting as solar maximum.

"Solar minimum is a quiet time when we can establish a baseline for evaluating long-term trends," he explains. "All stars are variable at some level, and the sun is no exception. We want to compare the sun's brightness now to its brightness during previous minima and ask: is the sun getting brighter or dimmer?"

The answer seems to be dimmer. Measurements by a variety of spacecraft indicate a 12-year lessening of the sun's "irradiance" by about 0.02% at visible wavelengths and 6% at EUV wavelengths. These results, which compare the solar minimum of 2008-09 to the previous minimum of 1996, are still very preliminary. EVE will improve confidence in the trend by pinning down the EUV spectrum with unprecedented accuracy.

The sun's variability and its potential for future changes are not fully understood—hence the need for EVE. "The EUV portion of the sun's spectrum is what changes most during a solar cycle," says Woods, "and that is the part of the spectrum we will be observing."

Woods gazes out his office window at the Colorado sun. It looks the same as usual. EVE, he knows, will have a different story to tell.

2010 Systems Engineering Excellence Award

NASA's Office of the Chief Engineer has announced the recipients of the first NASA Systems Engineering Award, including two people from NASA Ames Research Center. Bill Borucki, will receive a methodology award for the Kepler mission, and Daniel Andrews will receive a project award for the LCROSS mission.

Systems engineering is a core competency of NASA's highly skilled workforce and has been recognized as one of the "secrets" of the agency’s success in the Apollo program and many other programs and projects since then. NASA teams and organizations are increasingly employing well-defined, proven processes and practices to develop, manage, and integrate increasingly complex systems.

Each NASA center nominated several highly deserving projects and each was worthy of recognition. After a very difficult and competitive review process the Office of the Chief Engineer is pleased to announce the 2010 award recipients.

2010 Award Recipients:

  • Preston Burch, Hubble
  • Craig Tooley, LRO
  • Ab Davis, Grace Mission
  • Daniel Andrews, LCROSS
  • Dawn Schaible, MLAS
  • William Borucki, Discovery/Kepler Science Merit Function
  • Riley Duren, Discovery/Kepler Science Merit Function
  • Peter Parker, Shuttle Gaseous Hydrogen Valve
Award recipients will be honored on Feb. 10 at the 2010 NASA Project Management Challenge in Galveston, Texas.

For more information about the Office of the Chief Engineer, visit:
http://nen.nasa.gov/portal/site/llis/home/

Eclipses During 2010

During the year 2010, two solar and two lunar eclipses occur as follows:

2010 Jan 15: Annular Solar Eclipse
2010 Jun 26: Partial Lunar Eclipse
2010 Jul 11: Total Solar Eclipse
2010 Dec 21: Total Lunar Eclipse

Predictions for the eclipses are summarized in Figures 1, 2, 3, and 4. World maps show the regions of visibility for each eclipse. The lunar eclipse diagrams also include the path of the Moon through Earth's shadows. Contact times for each principal phase are tabulated along with the magnitudes and geocentric coordinates of the Sun and Moon at greatest eclipse.

All times and dates used in this publication are in Universal Time or UT. This astronomically derived time system is colloquially referred to as Greenwich Mean Time or GMT. To learn more about UT and how to convert UT to your own local time, see Time Zones and Universal Time.


Annular Solar Eclipse of January 15

The first solar eclipse of 2010 occurs at the Moon's ascending node in western Sagittarius. An annular eclipse will be visible from a 300-km-wide track that traverses central Africa, the Indian Ocean and eastern Asia (Espenak and Anderson, 2008). A partial eclipse is seen within the much broader path of the Moon's penumbral shadow, which includes eastern Europe, most of Africa, Asia, and Indonesia (Figure 1).

The annular path begins in westernmost Central African Republic at 05:14 UT. Because the Moon passes through apogee two days later (Jan 17 at 01:41 UT), its large distance from Earth produces an unusually wide path of annularity. Traveling eastward, the shadow quickly sweeps through Uganda, Kenya, and southern Somalia while the central line duration of annularity grows from 7 to 9 minutes.

For the next two hours, the antumbra crosses the Indian Ocean, its course slowly curving from east-southeast to northeast. The instant of greatest eclipse [1] occurs at 07:06:33 UT when the eclipse magnitude [2] will reach 0.9190. At this instant, the duration of annularity is 11 minutes 8 seconds, the path width is 333 kilometers and the Sun is 66° above the flat horizon formed by the open ocean. Such a long annular duration will not be exceeded for over 1000 years (3043 Dec 23).

The central track continues northeast where it finally encounters land in the Maldive Islands (07:26 UT). The capital city Male experiences an annular phase lasting 10 minutes 45 seconds This is the longest duration of any city having an international airport in the eclipse track.

When the antumbra reaches Asia the central line passes directly between the southern tip of India and northern Sri Lanka (07:51 UT). Both regions lie within the path where maximum annularity lasts 10 minutes 15 seconds Quickly sweeping over the Bay of Bengal the shadow reaches Burma where the central line duration is 8 minutes 48 seconds and the Sun's altitude is 34°.

By 08:41 UT, the central line enters China. The shadow crosses the Himalayas through Yunnan and Sichuan provinces Chongqing lies directly on the central line and witnesses a duration of 7 minutes 50 seconds with the Sun 15° above the horizon. Racing through parts of Shaanxi and Hubei provinces, the antumbra's speed increases as the duration decreases. In its final moments, the antumbra travels down the Shandong Peninsula and leaves Earth's surface (08:59 UT).

During the course of its 3 3/4-hour trajectory, the antumbra's track is approximately 12,900 km long that covers 0.87% of Earth's surface area. Path coordinates and central line circumstances are presented in Table 1.

Partial phases of the eclipse are visible primarily from Africa, Asia and Indonesia. Local circumstances for a number of cities are found in Table 2. All times are given in Universal Time. The Sun's altitude and azimuth, the eclipse magnitude and obscuration3 are all given at the instant of maximum eclipse.

This is the 23rd eclipse of Saros 141 (Espenak and Meeus, 2006). The family began with a series of 6 partial eclipses starting on 1613 May 19. The first annular eclipse took place on 1739 Aug 04 and had a maximum duration just under 4 minutes. Subsequent members of Saros 141 were all annular eclipses with increasing durations, the maximum of which was reached on 1955 Dec 14 and lasted 12 minutes 9 seconds. This event was the longest annular eclipse of the entire Second Millennium. The duration of annularity of each succeeding eclipse is now dropping and will dwindle to 1 minute 9 seconds when the last annular eclipse of the series occurs on 2460 Oct 14. Saros 141 terminates on 2857 Jun 13 after a long string of 22 partial eclipses. Complete details for the 70 eclipses in the series (29 partial and 41 annular) may be found at:

eclipse.gsfc.nasa.gov/SEsaros/SEsaros141.html

Complete details including many tables, maps and weather prospects can be found in the NASA 2010 eclipse bulletin (Espenak and Anderson, 2008) and online at:

eclipse.gsfc.nasa.gov/SEmono/ASE2010/ASE2010.html

Finally, a web-based zoomable map of the 2010 annular eclipse path is available plotted on Google maps at:

eclipse.gsfc.nasa.gov/SEgoogle/SEgoogle2001/SE2010Jan15Agoogle.html


Partial Lunar Eclipse of June 26

The first lunar eclipse of 2010 occurs at the Moon's ascending node in western Sagittarius about 3° east of the Lagoon Nebula (M8). It is visible from much of the Americas, the Pacific and eastern Asia (Figure 2). The Moon's contact times with Earth's shadows are listed below.

Penumbral Eclipse Begins:   08:57:21 UT
Partial Eclipse Begins: 10:16:57 UT
Greatest Eclipse: 11:38:27 UT
Partial Eclipse Ends: 12:59:50 UT
Penumbral Eclipse Ends: 14:19:34 UT

At the instant of greatest eclipse4 the umbral eclipse magnitude5 will reach 0.5368. At that time the Moon will be at the zenith for observers in the South Pacific. In spite of the fact that barely half of the Moon enters the umbral shadow (the Moon's northern limb dips 16.2 arc-minutes into the umbra), the partial phase still lasts 2 2/3 hours.

Figure 2 shows the path of the Moon through the penumbra and umbra as well as a map of Earth showing the regions of eclipse visibility. New England and eastern Canada will miss the entire eclipse since the event begins after moonset from those regions. Observers in western Canada and the USA will have the best views with moonset occurring sometime after mid-eclipse. To catch the entire event, one must be located in the Pacific or eastern Australia.

Table 3 lists predicted umbral immersion and emersion times for 15 well-defined lunar craters. The timing of craters is useful in determining the atmospheric enlargement of Earth's shadow (see Crater Timings During Lunar Eclipses).

The June 26 partial lunar eclipse belongs to Saros 120, a series of 83 eclipses in the following sequence: 21 penumbral, 7 partial, 25 total, 7 partial, and 23 penumbral lunar eclipses (Espenak and Meeus, 2009). Complete details for the series can be found at:

eclipse.gsfc.nasa.gov/LEsaros/LEsaros120.html


Total Solar Eclipse of July 11

The second solar eclipse of 2010 occurs at the Moon's descending node in central Gemini just 45 arc-minutes east of the 3rd magnitude star Delta Geminorum. The path of the Moon's umbral shadow crosses the South Pacific Ocean where it makes no landfall except for Mangaia (Cook Islands), Easter Island (Isla de Pascua) and several isolated atolls. The path of totality ends just after reaching southern Chile and Argentina (Espenak and Anderson, 2008). The Moon's penumbral shadow produces a partial eclipse visible from a much larger region covering the South Pacific and southern South America (Figure 3).

The central eclipse path begins in the South Pacific about 700 km southeast of Tonga at 18:15 UT. Traveling northeast, the track misses Rarotonga - the largest and most populous of the Cook Islands - by just 25 km. The first landfall occurs at Mangaia where the total eclipse lasts 3 minutes 18 seconds with the Sun 14° above the horizon.

The southern coast line of French Polynesia's Tahiti lies a tantalizing 20 km north of the eclipse path and experiences a deep 0.996 magnitude partial eclipse at 18:28 UT. Several cruises are already scheduled to intercept the umbral shadow from Papeete.

Greatest eclipse occurs in the South Pacific at 19:33:31 UT. At this instant, the axis of the Moon's shadow passes closest to Earth's center. The maximum duration of totality is 5 minutes 20 seconds, the Sun's altitude is 47°, and the path width is 259 km. Continuing across the vast Pacific, the umbral shadow's path encounters Easter Island, one of the most remote locations on Earth. From the capital, Hanga Roa, totality lasts 4 minutes 41 seconds with the Sun 40° above the horizon (20:11 UT). The 3,800 inhabitants of the isle are accustomed to tourism, but the eclipse is expected to bring record numbers to this unique destination.

The Moon's shadow sweeps across another 3700 km of open ocean before beginning its final landfall along the rocky shores of southern Chile at 20:49 UT. The shadow is now an elongated ellipse and its increasing ground velocity brings with it a corresponding decrease in the duration of totality. It is mid-winter in the Andes so clouds and high mountain peaks threaten to block views of the total eclipse. Nevertheless some hearty eclipse observers will find Argentina's tourist village of El Calafate a prime destination for the eclipse. The Sun's altitude is only 1° during the 2 minute 47 second total phase, but the lake may offer an adequate line-of-site to the eclipse hanging just above the rugged Andes skyline.

The path ends in southern Argentina when the umbra slips off Earth's surface as it returns to space (20:52 UT). Over the course of 2 2/3 hours, the umbra travels along a track approximately 11,100 km long that covers 0.48% of Earth's surface area. It will be 29 months before the next total solar eclipse occurs on 2012 Nov 13.

Path coordinates and central line circumstances are presented in Table 4. Local circumstances for a number of cities are listed in Table 5. All times are given in Universal Time. The Sun's altitude and azimuth, the eclipse magnitude and obscuration are all given at the instant of maximum eclipse.

This is the 27th eclipse of Saros 146 (Espenak and Meeus, 2006). The series began on 1541 Sep 19 with the first of an unusually long series of 22 partial eclipses. The first central eclipse was total with a maximum duration of 4.1 minutes on 1938 May 29. Subsequent total eclipses in the series have seen an increase in the duration of totality. The 2010 eclipse marks the longest totality of Saros 146 because future durations will decrease. The series produces the first of 4 hybrid eclipses on 2172 Oct 17. The remaining 24 central eclipses of Saros 141 are all annular and span the period from 2244 Dec 01 to 2659 Aug 10. The series ends with a set of 13 partial eclipses the last of which occurs on 2893 Dec 29.

In all, Saros 146 produces 35 partial, 13 total, 4 hybrid and 24 annular eclipses. Complete details for the series can be found at:

eclipse.gsfc.nasa.gov/SEsaros/SEsaros146.html

Complete details including many tables, maps and weather prospects can be found in the NASA 2010 eclipse bulletin (Espenak and Anderson, 2008) and online at:

eclipse.gsfc.nasa.gov/SEmono/TSE2010/TSE2010.html

Finally, a web-based zoomable map of the 2010 total eclipse path is available plotted on Google maps at:

eclipse.gsfc.nasa.gov/SEgoogle/SEgoogle2001/SE2010Jul11Tgoogle.html


Total Lunar Eclipse of December 21

The last lunar eclipse of 2010 is especially well placed for observers throughout North America. The eclipse occurs at the Moon's descending node in eastern Taurus, four days before perigee.

The Moon's orbital trajectory takes it through the northern half of Earth's umbral shadow. Although the eclipse is not central, the total phase still lasts 72 minutes. The Moon's path through Earth's shadows as well as a map illustrating worldwide visibility of the event are shown in Figure 4. The timings of the major eclipse phases are listed below.

Penumbral Eclipse Begins:   05:29:17 UT
Partial Eclipse Begins: 06:32:37 UT
Total Eclipse Begins: 07:40:47 UT
Greatest Eclipse: 08:16:57 UT
Total Eclipse Ends: 08:53:08 UT
Partial Eclipse Ends: 10:01:20 UT
Penumbral Eclipse Ends: 11:04:31 UT

At the instant of greatest eclipse (08:17 UT) the Moon lies near the zenith for observers in southern California and Baja Mexico. At this time, the umbral magnitude peaks at 1.2561 as the Moon's southern limb passes 2.8 arc-minutes north of the shadow's central axis. In contrast, the Moon's northern limb lies 8.1 arc-minutes from the northern edge of the umbra and 34.6 arc-minutes from the shadow center. Thus, the southern half of the Moon will appear much darker than the northern half because it lies deeper in the umbra. Since the Moon samples a large range of umbral depths during totality, its appearance will change dramatically with time. It is not possible to predict the exact brightness distribution in the umbra, so observers are encouraged to estimate the Danjon value at different times during totality (see Danjon Scale of Lunar Eclipse Brightness). Note that it may also be necessary to assign different Danjon values to different portions of the Moon (i.e., north vs. south).

During totality, the winter constellations are well placed for viewing so a number of bright stars can be used for magnitude comparisons. Pollux (mv = +1.16) is 25° east of the eclipsed Moon, while Betelgeuse (mv = +0.45) is 16° to the south, Aldebaran (mv = +0.87) is 20° to the west, and Capella (mv = +0.08) is 24° to the north.

The entire event is visible from North America and western South America. Observers along South America's east coast miss the late stages of the eclipse because they occur after moonset. Likewise much of Europe and Africa experience moonset while the eclipse is in progress. Only northern Scandinavians can catch the entire event from Europe. For observers in eastern Asia the Moon rises in eclipse. None of the eclipse is visible from south and east Africa, the Middle East or South Asia.

Table 6 lists predicted umbral immersion and emersion times for 20 well-defined lunar craters. The timing of craters is useful in determining the atmospheric enlargement of Earth's shadow (see Crater Timings During Lunar Eclipses).

The December 21 total lunar eclipse belongs to Saros 125 a series of 72 eclipses in the following sequence: 17 penumbral, 13 partial, 26 total, 9 partial, and 7 penumbral lunar eclipses (Espenak and Meeus, 2009). Complete details for the series can be found at:

eclipse.gsfc.nasa.gov/LEsaros/LEsaros125.html


Solar Eclipse Figures

Lunar Eclipse Figures

Shadow Diameters and Lunar Eclipses

Danjon Scale of Lunar Eclipse Brightness

Crater Timings During Lunar Eclipses


Eclipse Altitudes and Azimuths

The altitude a and azimuth A of the Sun or Moon during an eclipse depend on the time and the observer's geographic coordinates. They are calculated as follows:

h = 15 (GST + UT - α ) + λ
a = arcsin [sin δ sin φ + cos δ cos h cos φ]
A = arctan [-(cos δ sin h)/(sin δ cos φ - cos δ cos h sin φ)]

where

h = hour angle of Sun or Moon
a = altitude
A = azimuth
GST = Greenwich Sidereal Time at 0:00 UT
UT = Universal Time
α = right ascension of Sun or Moon
δ = declination of Sun or Moon
λ = observer's longitude (east +, west -)
φ = observer's latitude (north +, south -)

During the eclipses of 2010, the values for GST and the geocentric Right Ascension and Declination of the Sun or the Moon (at greatest eclipse) are as follows:

Eclipse             Date          GST         α         δ

Annular Solar 2010 Jan 15 7.642 19.797 -21.127
Partial Lunar 2010 Jun 26 18.299 18.353 -24.002
Total Solar 2010 Jul 11 19.307 7.399 22.036
Total Lunar 2010 Dec 21 5.986 5.955 23.746

Two web based tools that can also be used to calculate the local circumstances for all solar and lunar eclipses visible from any location. They are the Javascript Solar Eclipse Explorer and the Javascript Lunar Eclipse Explorer. The URLs for these tools are:

Javascript Solar Eclipse Explorer: eclipse.gsfc.nasa.gov/JSEX/JSEX-index.html

Javascript Lunar Eclipse Explorer: eclipse.gsfc.nasa.gov/JLEX/JLEX-index.html


Eclipses During 2011

During 2011, there will be four partial solar eclipses and two total lunar eclipses:

A full report on eclipses during 2011 will be published in Observer's Handbook 2011.


NASA Solar Eclipse Bulletins

Special bulletins containing detailed predictions and meteorological data for future solar eclipses of interest are prepared by Fred Espenak and Jay Anderson and are published through NASA's Publication series. The bulletins are provided as a public service to both the professional and lay communities, including educators and the media. A list of currently available bulletins and an order form can be found at:

eclipse.gsfc.nasa.gov/SEpubs/RPrequest.html

The most recent bulletin of the series covers the annular and total solar eclipses of 2010. Single copies of the eclipse bulletins are available at no cost by sending a 9 x 12-in. self-addressed envelope stamped with postage for 11 oz. (310 g). Please print the eclipse year on the envelope's lower left corner. Use stamps only, since cash and cheques cannot be accepted. Requests from outside the United States and Canada may include 10 international postal coupons. Mail requests to: Fred Espenak, NASA's Goddard Space Flight Center, Code 693, Greenbelt MD 20771, USA.

The NASA eclipse bulletins are also available over the Internet, including out-of-print bulletins. They can be read or downloaded from the NASA Eclipse Web Site at:

eclipse.gsfc.nasa.gov/SEpubs/bulletin.html


Eclipse Web Sites

The URL of the NASA Eclipse Web Site is:

eclipse.gsfc.nasa.gov/eclipse.html

The site features predictions and maps for all solar and lunar eclipses well into the 21st century, with special emphasis on upcoming eclipses. Special pages are devoted to the total solar eclipses of 2008, 2009 and 2010 that feature detailed maps, tables, graphs, and meteorological data. A world atlas of solar eclipses provides maps of all central eclipse paths from 2000 BCE to 3000 CE. The entire Five Millenium Canon of Solar Eclipses [Espenak and Meeus, 2006] can be downloaded in PDF format and all maps are also available online as individual GIFs of PSFs. Additional catalogues list every solar and lunar eclipse over a 5000-year period.

Detailed information on solar and lunar eclipse photography and tips on eclipse observing and eye safety may be found at:

www.mreclipse.com


Acknowledgments

All eclipse predictions were generated on an Apple G4 iMac computer using algorithms developed from the Explanatory Supplement [1974] with additional algorithms from Meeus, Grosjean, and Vanderleen [1966]. The solar coordinates used in the eclipse predictions are based on VSOP87 [P. Bretagnon and G. Francou, 1988]. The lunar coordinates are based on ELP-2000/82 [M. Chapront-Touzé and J. Chapront, 1983]. For lunar eclipses, the diameter of the umbral and penumbral shadows were calculated using Danjon's rule of enlarging Earth's radius by 1/85 to compensate for the opacity of the terrestrial atmosphere; corrections for the effects of oblateness have also been included. Text and table composition was done on a Macintosh using Microsoft Word. Additional figure annotation was performed with Claris MacDraw Pro.

All calculations, diagrams, tables, and opinions presented in this paper are those of the author, and he assumes full responsibility for their accuracy.


Footnotes

[1] The instant of greatest eclipse occurs when the distance between the Moon's shadow axis and Earth's geocenter reaches a minimum.

[2] Eclipse magnitude is defined as the fraction of the Sun's diameter occulted by the Moon

[3] The sub-solar point is the geographic location where the Sun appears directly overhead (zenith).


References

Bretagnon P., Francou G., "Planetary Theories in rectangular and spherical variables: VSOP87 solution", Astron. and Astrophys., vol. 202, no. 309 (1988).

Chapront-Touzé, M and Chapront, J., "The Lunar Ephemeris ELP 2000," Astron. and Astrophys., vol. 124, no. 1, pp 50-62 (1983).

Chauvenet, W., Manual of Spherical and Practical Astronomy, Vol.1, 1891 (Dover edition 1961).

Danjon, A., "Les éclipses de Lune par la pénombre en 1951," L'Astronomie, 65, 51-53 (Feb. 1951).

Espenak, F., Fifty Year Canon of Solar Eclipses: 1986–2035, Sky Publishing Corp., Cambridge, MA, 1988.

Espenak, F., Fifty Year Canon of Lunar Eclipses: 1986–2035, Sky Publishing Corp., Cambridge, MA, 1989.

Espenak, F., and Anderson, J., Annular and Total Solar Eclipses of 2010, NASA TP–2008-214171, Goddard Space Flight Center, Greenbelt, MD, 2008.–

Espenak, F., and Meeus, J., Five Millennium Canon of Solar Eclipses: –2000 to +3000 (2000 BCE to 3000 CE), NASA TP–2006-214141, Goddard Space Flight Center, Greenbelt, MD, 2006.

Espenak, F., and Meeus, J., Five Millennium Canon of Lunar Eclipses: –2000 to +3000 (2000 BCE to 3000 CE), NASA TP–2009-214172, Goddard Space Flight Center, Greenbelt, MD, 2006.

Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac, Her Majesty's Nautical Almanac Office, London, 1974.

Littmann, M., Espenak, F., & Willcox, K., Totality—Eclipses of the Sun, 3rd Ed., Oxford University Press, New York, 2008.

Meeus, J., Grosjean, C.C., & Vanderleen, W., Canon of Solar Eclipses, Pergamon Press, New York, 1966.

Meeus, J. & Mucke, H., Canon of Lunar Eclipses: -2002 to +2526, Astronomisches Buro, Wien, 1979.

Total Solar Eclipse of 2010 July 11

On Sunday, 2010 July 11, a total eclipse of the Sun is visible from within a narrow corridor that traverses Earth's southern Hemisphere. The path of the Moon's umbral shadow crosses the South Pacific Ocean where it makes no landfall except for Mangaia (Cook Islands) and Easter Island (Isla de Pascua). The path of totality ends just after reaching southern Chile and Argentina. The Moon's penumbral shadow produces a partial eclipse visible from a much larger region covering the South Pacific and southern South America

2010 Total Solar Eclipse Global Map
Click to enlarge.

This web site has been established for the purpose of providing detailed predictions, maps, figures and information about this important event. The material here is adapted from Annular and Total Solar Eclipses of 2010 (NASA/TP-2008-214171). The publication date of this document is 2008 December. It is part of NASA's official eclipse bulletin publication series. Instructions and a form for ordering a hard copy of this publication can be found at: Order Form for NASA Eclipse Bulletins.

A special Web site is also available for the Annular Solar Eclipse of 2010 January 15.


Preliminary Look at the Total Solar Eclipse of 2010 July 11

This data is from a paper presented at: IAU Symposium 233 - Solar Activity and Its Magnetic Origin

See also: Eclipse Weather and Maps (Jay Anderson)


Interactive Map of the Path of Totality

An implementation of Google Map has been created which includes the central path of the 2010 total solar eclipse. This allows the user to select any portion of the path and to zoom in using either map data or Earth satellite data.


General Map of the Eclipse Path

The following map shows the overall regions of visibility of the partial eclipse as well as the path of the total eclipse through the Pacific Ocean, Chile and Argentina. It uses high resolution coastline data from the World Data Base II (WDB). Curves of maximum eclipse are included as well as the outline of the umbral shadow.

The map is available as a high resolution (300 dpi) PDF file.

Figure
Number
Title/Description Map
File
Figure 3.1 Orthographic (Global) Map of 2010 Total Solar Eclipse PDF

From NASA Tech. Pub. Annular and Total Solar Eclipses of 2010 (NASA/TP-2008-214171).


Detailed Maps of the Path of Totality

The following maps show path of the 2010 total eclipse in greater detail. They use high resolution coastline, city and highway data from the Digital Chart of the World (DCW). Each map was chosen to isolate a specific region along the the eclipse path. Curves of maximum eclipse are included as well as the outline of the umbral shadow. Within the umbral path, curves of constant duration have been plotted for totality.

The maps are available as high resolution (300 dpi) PDF files.

Figure
Number
Title/Description Map
File
Figure 3.2 Path of Totality - Mangaia, Cook Islands PDF
Figure 3.3 Path of Totality - Tahiti PDF
Figure 3.4 Path of Totality - Tuamotu Archipelago PDF
Figure 3.5 Path of Totality - Easter Island (Isla de Pascua) PDF
Figure 3.6 Path of Totality - Chile & Argentina PDF

From NASA Tech. Pub. Annular and Total Solar Eclipses of 2010 (NASA/TP-2008-214171).


Additional Figures

The following figures depict the lunar limb profile, and meteorological data along the eclipse path.

Figure
Number
Title/Description Figure
File
Figure 3.7 Lunar Limb Profile for 2010 July 11 at 19:30 UT PDF
Figure 3.8 Typical weather Systems in July PDF
Figure 3.9 Average Cloudiness in July Along the Eclipse Path PDF
Figure 3.10 Annual Precipitation Statistics along the Eclipse Path PDF

From NASA Tech. Pub. Annular and Total Solar Eclipses of 2010 (NASA/TP-2008-214171).


Eclipse Elements, Shadow Contacts and Path of Totality

The following tables give detailed predictions including the Besselian Elements, shadow contacts with Earth, path of the umbral shadow and topocentric data (with path corrections) along the path.

From NASA Tech. Pub. Annular and Total Solar Eclipses of 2010 (NASA/TP-2008-214171).


Coordinate Tables for the Path of Totality

The following tables do not appear in the NASA 2010 Eclipse Bulletin due to page constraints. The tables provide detailed coordinates for the path of the umbral shadow as well as the zones of grazing eclipse. They are listed in a format convenient for plotting on maps.


Local Circumstances

The following table gives the local circumstances of the eclipse from various cities throughout the region of eclipse visibility. All contact times are given in the tables are in Universal Time.

From NASA Tech. Pub. Annular and Total Solar Eclipses of 2010 (NASA/TP-2008-214171).


Additional Tables

The following tables also appear in the Annular and Total Solar Eclipses of 2010 (NASA/TP-2008-214171).


Explanation of Eclipse Maps and Tables

The following links give detailed descriptions and explanations of the eclipse maps and tables.


Reproduction of Eclipse Data

All eclipse calculations are by Fred Espenak, and he assumes full responsibility for their accuracy. Permission is freely granted to reproduce this data when accompanied by an acknowledgment:

"Eclipse Predictions by Fred Espenak, NASA's GSFC"

For more information, see: NASA Copyright Information

About LT Learning Technologies

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  • -- facilitate learning
  • -- complement standard curricula in science, technology, engineering and math, or STEM, teaching
  • -- be usable in today’s learning environments and
  • -- be engaging as well as educational.

Working with our academic and industry partners, our prototypes are evaluated and improved until they are classroom-ready.

The source code for many LT software products is licensable to academia or industry for further research, development or commercialization.

Initiatives LT's research and development focuses on several areas of the NASA eEducation agenda:

LT's research and development focuses on several areas of the NASA eEducation agenda:

    Games for Learning

      Astronaut: Moon, Mars and Beyond Promo

      Astronaut: Moon, Mars and Beyond

      • -- LT is partnering in the development of Astronaut: Moon, Mars and Beyond, a massively multiplayer online game (MMOG) that will include science, technology, engineering and mathematics learning and career exploration.
      • -- This game environment will provide NASA virtual, immersive educational experience to students and educators and will allow us to evaluate its effectiveness on student engagement and learning.

    Virtual Worlds

      Testing a virtual guide dog in Second Life

      LT Island Managers testing out Max the Virtual Guidedog from Virtual Helping Hands

      • -- LT is researching virtual worlds as platforms for learning, collaboration, networking and event delivery. We manage NASA eEducation Island in Second Life and are using this space to facilitate NASA education projects' entry into virtual worlds.
      • -- Building on prior research and development, LT's Information Accessibility Lab is collaborating with multiple industry and academic partners → on methods of making 3D virtual worlds accessible to the blind and visually-impaired.

    Electronic Professional Development

      A crowd watching a live video event at eEducation Island in Second Life.

      NASA Digital Learning Network Training in Second Life

      • -- LT is undertaking research into the best practices for professional development in online and virtual environments.
      • -- Particular attention is being paid to ways to best deliver training for using NASA educational materials.

Publications

  • -- Laughlin, D., Roper, M., Howell, K.,Research Challenges in the Design of Massively Multiplayer Games for Education and Training: NASA eEducation Roadmap, April 2007.
  • -- Laughlin, D., NASA eEducation Roadmap Implementation Guide, Internal NASA Document, March 2007.
    This document is intended as a research based outline of tasks for the NASA eEducation unit to implement some of the research and development areas identified by the NASA eEducation Roadmap.
  • -- Laughlin, D., Marchuk, N., A Guide to Educational Computer Games for NASA, November 2005.
    An NLT research white paper on the computer games as educational media. This document includes input solicited in a 2004 Request for Information.
  • -- Smith, Stephanie L., Second Life Mixed Reality Broadcasts: A Timeline of Practical Experiments at the NASA CoLab Island", Journal of Virtual Worlds Research, Volume 1, Number 1, July 2008.
  • -- Hoppin, A., Smith, Stephanie L., et al, "Framework and Implementation of the NGEC-2 Mixed Reality Broadcast", Proceedings of the Next Generation Exploration Conference-2: Entrepreneurial Opportunities in Lunar Development, Appendix D, NASA/CP-2008-214583, July 2008.

World Wind Java SDK

Welcome:
Here you will find the World Wind SDK for Java

With this SDK, developers can embed World Wind technology in their own applications. The API documentation will be made available later.

The discussion and help forum for the World Wind Java SDK can be found at World Wind Central. (informally affiliated with NASA)

Requirements: a 3D video card with updated drivers is necessary. World Wind has been tested on Nvidia, ATI/AMD, and Intel platforms using Windows, MacOS 10.4, and Fedora Core 6.

Note: Update your video card drivers.
(How to update windows drivers)
(ATI/AMD - Nvidia - Intel)



Administrative Contact:

Patrick Hogan
1 (650) 604-5656
Looking for the original .NET version of World Wind?
Visit the .NET download page.



Default Controls

Mouse with scroll wheel:

Pan:

Left mouse button click & drag - all directions

Zoom:

Use the scroll wheel on the mouse or
Left & Right mouse (both buttons) click & drag - up and down

Tilt: Right mouse button click & drag - up and down
or use "Page Up" and "Page Down" on the keyboard.
Rotate:

Right mouse button click & drag - left and right
Note: Crossing the top and bottom half of the screen while rotating will change direction.

Stop:

Spacebar

Reset Heading:

N

Reset all:

R

Single button mouse:

Pan:

Left mouse button click & drag - all directions
L left mouse button click once to center view.

Zoom:

Hold "Ctrl" on the keyboard and
Left mouse button click & drag - up and down

Tilt: Hold "Shift" on the keyboard and
Left mouse button click & drag - up and down
or use "Page Up" and "Page Down" on the keyboard.
Rotate: Hold "Shift" on the keyboard and
Left mouse button click & drag - left and right
Stop:

Spacebar

Reset Heading:

N

Reset all:

R



Known Issues

Image download speeds will vary, depending on your internet connection.

A blank screen is typically caused by out of date graphics drivers. Please update them from the graphics card manufacturer via the links above.