Skip to content
https://space.com

Lighthouse Desktop

· 0 checks — Desktop Lighthouse audit -- Performance, Accessibility, Best Practices, and SEO category breakdown.
SCORE
0
GRADE
FIX
0
REVIEW
0
PASS
0
INFO
0

Detailed Report

Audit breakdown by category with detailed findings.

78

Performance

Insights

Remove large, duplicate JavaScript modules from bundles to reduce unnecessary bytes consumed by network activity.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Polyfills and transforms enable older browsers to use new JavaScript features. However, many aren't necessary for modern browsers. Consider modifying your JavaScript build process to not transpile Baseline features, unless you know you must support older browsers. Learn why most sites can deploy ES6+ code without transpiling

Why this matters

Performance issues directly impact user engagement and conversion rates.

3rd party code can significantly impact load performance. Reduce and defer loading of 3rd party code to prioritize your page's content.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Layout shifts occur when elements move absent any user interaction. Investigate the causes of layout shifts, such as elements being added, removed, or their fonts changing as the page loads.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]
items: [map[node:map[type:text value:Total] score:0.000245] map[node:map[boundingRect:map[bottom:518 height:48 left:214 right:1136 top:470 width:922] lhId:page-6-P nodeLabel:The agency will unveil the Nancy Grace Roman Space Telescope on Tuesday (April … path:1,HTML,1,BODY,7,DIV,4,DIV,0,DIV,0,DIV,0,DIV,2,P selector:div#tag-page-content > div.wcp-item-content > div#tag-page-content > p#elk-351ad694-d0ca-4638-8c88-a3a9b54b94a1 snippet:<p id="elk-351ad694-d0ca-4638-8c88-a3a9b54b94a1"> type:node] score:0.000245]]
headings: [map[key:node label:Element subItemsHeading:map[key:extra] valueType:node] map[granularity:0.001 key:score label:Layout shift score subItemsHeading:map[key:cause valueType:text] valueType:numeric]]
items: [map[node:map[type:text value:Total] score:0.203667] map[node:map[boundingRect:map[bottom:0 height:0 left:0 right:0 top:0 width:0] lhId:page-7-META nodeLabel:head > meta path:1,HTML,0,HEAD,2,META selector:head > meta snippet:<meta name="viewport" content="width=device-width,initial-scale=1"> type:node] score:0.203667]]

A forced reflow occurs when JavaScript queries geometric properties (such as offsetWidth) after styles have been invalidated by a change to the DOM state. This can result in poor performance. Learn more about forced reflows and possible mitigations.

Why this matters

Performance issues directly impact user engagement and conversion rates.

headings: [map[key:source label:Source valueType:source-location] map[granularity:1 key:reflowTime label:Total reflow time valueType:ms]]
items: [map[reflowTime:64.179 source:map[column:10 line:7120 type:source-location url:https://www.space.com/ urlProvider:network]] map[reflowTime:40.65 source:map[type:text value:[unattributed]]] map[reflowTime:13.683 source:map[column:30557 line:0 type:source-location url:https://cdn.viafoura.net/entry/index.js urlProvider:network]]]

Reducing the download time of images can improve the perceived load time of the page and LCP. Learn more about optimizing image size

Why this matters

Performance issues directly impact user engagement and conversion rates.

URLResource SizeEst Savings
Watch live: NASA's Nancy Grace Roman Space Telescope is a game changer and full… div#elk-7tVFWBZq6Bc > div.video-aspect-box > div.watch-on-iframe-7tVFWBZq6Bc > img
img.youtube.com/vi/7tVFWBZq6Bc/maxresdefault.jpg185.6 KiB107.8 KiB
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
cdn.mos.cms.futurecdn.net/sUHwvwiEHhLpBHDjmM74yh-840-80.jpg.webp69.9 KiB61.8 KiB
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
cdn.mos.cms.futurecdn.net/eyaxArCZhsttPxnRbTbaJn-840-80.jpg.webp28.5 KiB24.9 KiB
A Pegasus XL rocket launches the "Founders Flight" for the space memorial compa… div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
cdn.mos.cms.futurecdn.net/7Y8QZPnvSaGMM9QESpWUiG-840-80.jpg.webp15.1 KiB12.2 KiB
A bunch of rocks in a sandy landscape div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
cdn.mos.cms.futurecdn.net/NWCUm5ztegN3ZrwmTfgDrc-320-80.jpg.webp14.6 KiB5.2 KiB
Screenshot from the sci-fi video game "Pragmata" div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
cdn.mos.cms.futurecdn.net/3Dr75uvYQFkFtrQhujK2NS-320-80.jpg.webp14.2 KiB4.8 KiB

Optimize LCP by making the LCP image discoverable from the HTML immediately, and avoiding lazy-loading

Why this matters

Performance issues directly impact user engagement and conversion rates.

lhId: page-0-IMG
nodeLabel: Watch live: NASA's Nancy Grace Roman Space Telescope is a game changer and full…
path: 1,HTML,1,BODY,7,DIV,4,DIV,0,DIV,0,DIV,0,DIV,3,DIV,0,DIV,0,DIV,1,IMG
selector: div#elk-7tVFWBZq6Bc > div.video-aspect-box > div.watch-on-iframe-7tVFWBZq6Bc > img
snippet: <img src="https://img.youtube.com/vi/7tVFWBZq6Bc/maxresdefault.jpg" alt="Watch live: NASA's Nancy Grace Roman Space Telescope is a game changer and…" data-aspect-ratio="16/9" loading="lazy">

Avoid chaining critical requests by reducing the length of chains, reducing the download size of resources, or deferring the download of unnecessary resources to improve page load.

Why this matters

Performance issues directly impact user engagement and conversion rates.

description: [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints help the browser establish a connection earlier in the page load, saving time when the first request for that origin is made. The following are the origins that the page preconnected to.
title: Preconnected origins
description: Add [preconnect](https://developer.chrome.com/docs/lighthouse/performance/uses-rel-preconnect/) hints to your most important origins, but try to use no more than 4.
title: Preconnect candidates
value: No additional origins are good candidates for preconnecting

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Consider setting font-display to swap or optional to ensure text is consistently visible. swap can be further optimized to mitigate layout shifts with font metric overrides.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Requests are blocking the page's initial render, which may delay LCP. Deferring or inlining can move these network requests out of the critical path.

Why this matters

Performance issues directly impact user engagement and conversion rates.

These insights are also available in the Chrome DevTools Performance Panel - record a trace to view more detailed information.

Redirects introduce additional delays before the page can be loaded. Learn how to avoid page redirects.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Estimated savings: 239 ms
URLTime Spent
space.com/239 ms
www.space.com/0.0 ms

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to windowing. Learn how to improve CLS

Why this matters

Performance issues directly impact user engagement and conversion rates.

ElementLayout shift score
head > meta head > meta
0.204
The agency will unveil the Nancy Grace Roman Space Telescope on Tuesday (April … div#tag-page-content > div.wcp-item-content > div#tag-page-content > p#elk-351ad694-d0ca-4638-8c88-a3a9b54b94a1
0.000

Time to Interactive is the amount of time it takes for the page to become fully interactive. Learn more about the Time to Interactive metric.

Why this matters

Performance issues directly impact user engagement and conversion rates.

TTI

Diagnostics

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. Learn how to reduce unused JavaScript.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. Learn how to minimize main-thread work

Why this matters

Performance issues directly impact user engagement and conversion rates.

CategoryTime Spent
Other1.8 s
Script Evaluation1.2 s
Style & Layout420 ms
Rendering193 ms
Script Parsing & Compilation135 ms
Garbage Collection53 ms
Parse HTML & CSS49 ms

Many navigations are performed by going back to a previous page, or forwards again. The back/forward cache (bfcache) can speed up these return navigations. Learn more about the bfcache

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failure reasonFailure type
The page has an unload handler in the main frame.Actionable
Pages with cache-control:no-store header cannot enter back/forward cache.Actionable
Pages whose main resource has cache-control:no-store cannot enter back/forward cache.Not actionable
Back/forward cache is disabled because some JavaScript network request received resource with Cache-Control: no-store header.Not actionable

More information about the performance of your application. These numbers don't directly affect the Performance score.

Max Potential First Input Delay 100 ms
Optimize DOM size
LCP breakdown
Modern HTTP
Optimize viewport for mobile
Minify CSS
Minify JavaScript
Reduce unused CSS
Avoids enormous network payloads Total size was 2,512 KiB
User Timing marks and measures 31 user timings
JavaScript execution time 1.0 s
Avoid long main-thread tasks 5 long tasks found
Image elements have explicit `width` and `height`
Network Requests
Network Round Trip Times 100 ms
Server Backend Latencies 30 ms
Tasks
Diagnostics
Metrics
Screenshot Thumbnails
Final Screenshot
Script Treemap Data
Resources Summary
Initial server response time was short Root document took 0 ms
INP breakdown
Avoid non-composited animations
87

Accessibility

These checks highlight opportunities to improve the accessibility of your web app. Automatic detection can only detect a subset of issues and does not guarantee the accessibility of your web app, so manual testing is also encouraged.

ARIA

Some ARIA roles have required attributes that describe the state of the element to screen readers. Learn more about roles and required attributes.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
MORE FROM SPACE... div#slice-container-popularBox > section.popular-box > div.popular-box__label > div.popular-box__label__tab

These are opportunities to improve the usage of ARIA in your application which may enhance the experience for users of assistive technology, like a screen reader.

Names and labels

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img

Link text (and alternate text for images, when used as links) that is discernible, unique, and focusable improves the navigation experience for screen reader users. Learn how to make links accessible.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.meganav-desktop__container > ul.meganav-desktop__list > li.meganav-item--home-link > a.meganav-item__link div.meganav-desktop__container > ul.meganav-desktop__list > li.meganav-item--home-link > a.meganav-item__link

These are opportunities to improve the semantics of the controls in your application. This may enhance the experience for users of assistive technology, like a screen reader.

Visible text labels that do not match the accessible name can result in a confusing experience for screen reader users. Learn more about accessible names.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
You've heard of the Space Force. Now there's a 'NASA Force' — but it's not abou… div.wdn-fte-rcr > div.list-text-links > div.listingResult > a.article-link
Bring nebulas and galaxies into focus with nearly $700 off this smart telescope div.wdn-fte-rcr > div.list-text-links > div.listingResult > a.article-link
'Dancing' jets erupting from a cannibalistic black hole have the power of 10,00… div.wdn-fte-rcr > div.list-text-links > div.listingResult > a.article-link
The moon and Jupiter steal the show after sunset on April 22 div.wdn-fte-rcr > div.list-text-links > div.listingResult > a.article-link
NASA rolls out Artemis 3 SLS rocket's huge core stage to gear up for 2027 launc… div.wdn-fte-rcr > div.list-text-links > div.listingResult > a.article-link
NASA reveals its Roman Space Telescope today: How to watch live, and what's nex… div.mainCarousel > section#homePageCarousel > div#Item1 > a.article-link
NASA shuts down Voyager 1 instrument to keep probe exploring interstellar space… div.mainCarousel > section#homePageCarousel > div#Item3 > a.article-link
On this day in space: April 21, 1997: 1st Space Funeral Launches on 'Founders F… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Aurora forecast April 21 — Northern lights linger as geomagnetic activity conti… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
How to see the Lyrid meteor shower tonight: Where to look in the night sky By … section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Astronauts photograph Lyrid meteor shower from ISS | Space photo of the day for… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
SpaceX launches advanced GPS satellite for US Space Force after rocket swap (vi… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
600 rocket landings! SpaceX notches another milestone during Sunday Starlink la… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Astronauts face grip strength challenge in space and on Earth, scientists find … section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Artemis Accords: What are they & which countries are involved? By Robert Lea l… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
What is the moon phase today? Lunar phases 2026 By Tariq Malik, Daisy Dobrijev… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
A peek at the far side of the moon | Space photo of the day for April 20, 2026 … section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Artemis 2 moon rocket rolls back to launch pad | Space photo of the day for Mar… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
SpaceX's Ship 39 is so cool in Starship V3 test | Space photo of the day for Ma… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Cosmic Hawk spreads its wings| Space photo of the day for March 6, 2026 By Rob… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Metroid games ranked, worst to best By Fran Ruiz last updated 9 hours ago We'… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
'80s sci-fi cult classic 'The Last Starfighter' finally scores a sequel, but it… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Disclosure day: If ET made contact, how would we handle the news? By Leonard D… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Where are all the aliens? Maybe they just don't want to talk to us By Leonard … section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
No sun, no problem? How life could thrive on moons of starless 'rogue' planets … section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Best VPN services we recommend 2026 By Alexander Cox last updated 8 hours ago … section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Max Space unveils new expandable space habitat for the moon and beyond: 'We nee… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
The best drone deals 2026: Fly high with fantastic savings By Alexander Cox la… section.listingResultsWrapper > div.listingResults > div.listingResult > a.article-link
Interactive controls are keyboard focusable
Interactive elements indicate their purpose and state
The page has a logical tab order
Visual order on the page follows DOM order
User focus is not accidentally trapped in a region
The user's focus is directed to new content added to the page
HTML5 landmark elements are used to improve navigation
Offscreen content is hidden from assistive technology
Custom controls have associated labels
Custom controls have ARIA roles
`[aria-*]` attributes match their roles
`[aria-hidden="true"]` is not present on the document `<body>`
`[role]` values are valid
`[aria-*]` attributes have valid values
`[aria-*]` attributes are valid and not misspelled
Buttons have an accessible name
`[user-scalable="no"]` is not used in the `<meta name="viewport">` element and the `[maximum-scale]` attribute is not less than 5.
`button`, `link`, and `menuitem` elements have accessible names
ARIA attributes are used as specified for the element's role
Elements with `role="dialog"` or `role="alertdialog"` have accessible names.
`[aria-hidden="true"]` elements do not contain focusable descendents
Elements use only permitted ARIA attributes
Background and foreground colors have a sufficient contrast ratio
Document has a `<title>` element
`<frame>` or `<iframe>` elements have a title
`<html>` element has a `[lang]` attribute
`<html>` element has a valid value for its `[lang]` attribute
Links are distinguishable without relying on color.
Lists contain only `<li>` elements and script supporting elements (`<script>` and `<template>`).
List items (`<li>`) are contained within `<ul>`, `<ol>` or `<menu>` parent elements
No element has a `[tabindex]` value greater than 0
Touch targets have sufficient size and spacing.
Heading elements appear in a sequentially-descending order
Skip links are focusable.
Document has a main landmark.
Deprecated ARIA roles were not used
Uses ARIA roles only on compatible elements
Image elements do not have `[alt]` attributes that are redundant text.
Identical links have the same purpose.
`[accesskey]` values are unique
ARIA input fields have accessible names
ARIA `meter` elements have accessible names
ARIA `progressbar` elements have accessible names
Elements with an ARIA `[role]` that require children to contain a specific `[role]` have all required children.
`[role]`s are contained by their required parent element
Elements with the `role=text` attribute do not have focusable descendents.
ARIA toggle fields have accessible names
ARIA `tooltip` elements have accessible names
ARIA `treeitem` elements have accessible names
The page contains a heading, skip link, or landmark region
`<dl>`'s contain only properly-ordered `<dt>` and `<dd>` groups, `<script>`, `<template>` or `<div>` elements.
Definition list items are wrapped in `<dl>` elements
ARIA IDs are unique
No form fields have multiple labels
`<html>` element has an `[xml:lang]` attribute with the same base language as the `[lang]` attribute.
Input buttons have discernible text.
`<input type="image">` elements have `[alt]` text
Form elements have associated labels
The document does not use `<meta http-equiv="refresh">`
`<object>` elements have alternate text
Select elements have associated label elements.
Cells in a `<table>` element that use the `[headers]` attribute refer to table cells within the same table.
`<th>` elements and elements with `[role="columnheader"/"rowheader"]` have data cells they describe.
`[lang]` attributes have a valid value
`<video>` elements contain a `<track>` element with `[kind="captions"]`
Tables have different content in the summary attribute and `<caption>`.
All heading elements contain content.
Tables use `<caption>` instead of cells with the `[colspan]` attribute to indicate a caption.
`<td>` elements in a large `<table>` have one or more table headers.
81

Best Practices

General

Deprecated APIs will eventually be removed from the browser. Learn more about deprecated APIs.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Deprecation / WarningSource
Unload event listeners are deprecated and will be removed.
Uses HTTPS
Avoids third-party cookies
Allows users to paste into input fields
Avoids requesting the geolocation permission on page load
Avoids requesting the notification permission on page load
Displays images with correct aspect ratio
Serves images with appropriate resolution
Page has the HTML doctype
Properly defines charset
No browser errors logged to the console
No issues in the `Issues` panel in Chrome Devtools
Ensure CSP is effective against XSS attacks
Use a strong HSTS policy
Ensure proper origin isolation with COOP
Mitigate DOM-based XSS with Trusted Types
Detected JavaScript libraries
Page has valid source maps
Redirects HTTP traffic to HTTPS
Mitigate clickjacking with XFO or CSP
85

SEO

These checks ensure that your page is following basic search engine optimization advice. There are many additional factors Lighthouse does not score here that may affect your search ranking, including performance on Core Web Vitals. Learn more about Google Search Essentials.

Crawling and Indexing

Search engines may use `href` attributes on links to crawl websites. Ensure that the `href` attribute of anchor elements links to an appropriate destination, so more pages of the site can be discovered. Learn how to make links crawlable

Why this matters

Performance issues directly impact user engagement and conversion rates.

Uncrawlable Link
REFERENCE section.listingResultsWrapper > div.listingResults > div.listingResult > a.category-link
REFERENCE section.listingResultsWrapper > div.listingResults > div.listingResult > a.category-link

To appear in search results, crawlers need access to your app.

Content Best Practices

Informative elements should aim for short, descriptive alternate text. Decorative elements can be ignored with an empty alt attribute. Learn more about the `alt` attribute.

Why this matters

Performance issues directly impact user engagement and conversion rates.

Failing Elements
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img
div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img div.image-remove-flow-width-setter > div.image-remove-reflow-container > picture > img

Format your HTML in a way that enables crawlers to better understand your app’s content.

Structured data is valid
Page isn’t blocked from indexing
Document has a `<title>` element
Document has a meta description
Page has successful HTTP status code
Links have descriptive text
robots.txt is valid
Document has a valid `hreflang`
Document has a valid `rel=canonical`

Send Feedback