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sun science

Sunlight shines through a paper with cutouts that casts the words “Science Friday Educate” as a shadow.

The Science Of Sunlight And Shadows

Track sunlight and shadows as you investigate the science behind day and night, the seasons, and eclipses.

Make a UV Detector

On a bright, sunny day, use tonic water to detect ultraviolet (UV) light from the Sun in this DIY Sun Science Activity from Lawrence Hall of Science.

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Cookie	Duration	Description
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Cookie	Duration	Description
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Performance

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Cookie	Duration	Description
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_gat	1 minute	This cookie is installed by Google Universal Analytics to restrain request rate and thus limit the collection of data on high traffic sites.
_gat_UA-28243511-22	1 minute	A variation of the _gat cookie set by Google Analytics and Google Tag Manager to allow website owners to track visitor behaviour and measure site performance. The pattern element in the name contains the unique identity number of the account or website it relates to.
AWSALB	7 days	AWSALB is an application load balancer cookie set by Amazon Web Services to map the session to the target.
countryCode	session	This cookie is used for storing country code selected from country selector.

Audience Measurement

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Cookie	Duration	Description
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IDE	1 year 24 days	Google DoubleClick IDE cookies are used to store information about how the user uses the website to present them with relevant ads and according to the user profile.
NID	6 months	NID cookie, set by Google, is used for advertising purposes; to limit the number of times the user sees an ad, to mute unwanted ads, and to measure the effectiveness of ads.
personalization_id	2 years	Twitter sets this cookie to integrate and share features for social media and also store information about how the user uses the website, for tracking and targeting.
test_cookie	15 minutes	The test_cookie is set by doubleclick.net and is used to determine if the user's browser supports cookies.
vglnk.Agent.p	1 year	VigLink sets this cookie to track the user behaviour and also limit the ads displayed, in order to ensure relevant advertising.
vglnk.PartnerRfsh.p	1 year	VigLink sets this cookie to show users relevant advertisements and also limit the number of adverts that are shown to them.
VISITOR_INFO1_LIVE	5 months 27 days	A cookie set by YouTube to measure bandwidth that determines whether the user gets the new or old player interface.
YSC	session	YSC cookie is set by Youtube and is used to track the views of embedded videos on Youtube pages.
yt-remote-connected-devices	never	YouTube sets this cookie to store the video preferences of the user using embedded YouTube video.
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Others

Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet.

Cookie	Duration	Description
_dc_gtm_UA-28243511-20	1 minute	No description
abtest-identifier	1 year	No description
AnalyticsSyncHistory	1 month	No description
ARRAffinityCU	session	No description available.
ccc	1 month	No description
COMPASS	1 hour	No description
cookies.js_dtest	session	No description
debug	never	No description available.
donation-identifier	1 year	No description
f	never	No description available.
GFE_RTT	5 minutes	No description available.
incap_ses_1185_2233503	session	No description
incap_ses_1185_823975	session	No description
incap_ses_1185_972453	session	No description
incap_ses_1319_2233503	session	No description
incap_ses_1319_823975	session	No description
incap_ses_1319_972453	session	No description
incap_ses_1364_2233503	session	No description
incap_ses_1364_823975	session	No description
incap_ses_1364_972453	session	No description
incap_ses_1580_2233503	session	No description
incap_ses_1580_823975	session	No description
incap_ses_1580_972453	session	No description
incap_ses_198_2233503	session	No description
incap_ses_198_823975	session	No description
incap_ses_198_972453	session	No description
incap_ses_340_2233503	session	No description
incap_ses_340_823975	session	No description
incap_ses_340_972453	session	No description
incap_ses_374_2233503	session	No description
incap_ses_374_823975	session	No description
incap_ses_374_972453	session	No description
incap_ses_375_2233503	session	No description
incap_ses_375_823975	session	No description
incap_ses_375_972453	session	No description
incap_ses_455_2233503	session	No description
incap_ses_455_823975	session	No description
incap_ses_455_972453	session	No description
incap_ses_8076_2233503	session	No description
incap_ses_8076_823975	session	No description
incap_ses_8076_972453	session	No description
incap_ses_867_2233503	session	No description
incap_ses_867_823975	session	No description
incap_ses_867_972453	session	No description
incap_ses_9117_2233503	session	No description
incap_ses_9117_823975	session	No description
incap_ses_9117_972453	session	No description
li_gc	2 years	No description
loglevel	never	No description available.
msToken	10 days	No description