Articles by Tim Sharp, Reference editor

Tim Sharp is the Reference Editor for Space.com. He manages articles that explain scientific concepts, describe natural phenomena and define technical terms. Previously, he was a Technology Editor at The New York Times and the Online Editor at the Des Moines Register. He was also a copy editor at several newspapers. Before joining Purch, Tim was a developmental editor at the Hazelden Foundation. He has a journalism degree from the University of Kansas. Follow Tim on Google+ and @therealtimsharp

Articles by: Tim Sharp

The sun's atmosphere is home to events such as this coronal mass injection (CME) on the sun imaged by the LASCO C2 coronagraph instrument on the ESA-NASA SOHO spacecraft.

The sun's atmosphere: Photosphere, chromosphere and corona

By Tim Sharp last updated 21 June 22

Reference The sun's atmosphere has three layers: The photosphere, the chromosphere and the corona.

A photo of the first commercial airline flight, a small, two-passenger plane flying over Tampa Bay.

The world's first commercial airline

By Tim Sharp published 1 March 22

The first scheduled passenger airline service flew from St. Petersburg to Tampa, FL in 1914.

Illustration of the temperature on the moon showing the moon against a background of stars. A large question mark is in front of the moon and a cartoon thermometer is to the left.

What is the temperature on the moon?

By Tim Sharp, Doris Elin Urrutia last updated 5 May 23

Reference We explore what the temperature is on the moon and see why it varies so considerably.

How far is the moon from Earth?

By Doris Elin Urrutia, Tim Sharp last updated 18 November 22

Reference Answering the question "how far is the moon from Earth?", can change depending on when you ask it. The average distance between Earth and the moon is about 238,855 miles (384,400 kilometers).

Temperature on Earth graphic illustration on map.

What is the average temperature on Earth?

By Tim Sharp, Vicky Stein last updated 20 September 23

Reference Earth's global average surface temperature is approximately 59 degrees Fahrenheit (15 degrees Celsius). But it's on the rise.

graphic illustration of mars showing a rusty red surface and light from the distant sun in the upper right corner.

Mars' atmosphere: Facts about composition and climate

By Daisy Dobrijevic last updated 17 September 23

Reference Mars' atmosphere is over 100 times thinner than Earth's and is primarily composed of carbon dioxide, nitrogen and argon gases.

The temperature on Mars is much colder than the average temperature on Earth and thanks to the NASA’s Perseverance Rover we're getting new data all the time.

What is the temperature on Mars?

By Tim Sharp, Jonathan Gordon last updated 25 February 22

Reference The temperature on Mars doesn't get much above 70 degrees F and it drop down to nearly minus 200 degrees F, making it a relatively cold planet.

How big is the moon?

By Daisy Dobrijevic, Tim Sharp last updated 7 February 22

Reference How big is the moon? Our moon is the fifth largest moon in the solar system, with a radius of 1,079.6 miles (1,737.5 kilometers).

What is the sun made of?

By Tim Sharp, Ailsa Harvey published 27 January 22

Reference What is the sun made of? In several layers, hot gases are converted into energy and released as heat and light.

How big is the sun?

By Tim Sharp, Ailsa Harvey published 21 January 22

Reference Earth's star is the largest and the most massive object in the solar system. More than one million Earths could fit inside the sun.

The average distance between the Earth and the sun is an astronomical unit.

How far is Earth from the sun?

By Tim Sharp, Doris Elin Urrutia published 21 January 22

Earth's distance from the sun does not stay the same throughout the year.

thin blue haze of earth's atmosphere with the moon shining above.

Earth's atmosphere: Facts about our planet's protective blanket

By Tim Sharp, Daisy Dobrijevic last updated 23 July 23

Reference Earth's atmosphere protects the planet and sustains life.

How big is Earth?

By Tim Sharp published 6 July 21

How big is Earth? Earth is the fifth-largest planet in the solar system and the densest.

The first free ascent of a hot-air balloon with human passengers, on Nov. 21, 1783. — Jean-François Pilâtre de Rozier and the Marquis d´Arlandes

The First Hot-Air Balloon Flight

By Tim Sharp published 9 April 19

In 1783, the Montgolfier brothers' plan to reach the sky was full of hot air.

5 Years After SpaceShipOne: Commercial Spaceflight Ready for 'Go'

SpaceShipOne: The First Private Spacecraft

By Tim Sharp published 5 March 19

SpaceShipOne launched the era of private spaceflight.

Edmond Halley: An Extraordinary Scientist and the Second Astronomer Royal

By Tim Sharp published 11 December 18

Saturn V Rockets & Apollo Spacecraft

By Tim Sharp last updated 29 April 22

To get astronauts to the moon, scientists built the largest rocket ever.

Artist's conception of our solar system's solar nebula, the cloud of gas and dust from which the planets formed.

How Was Mars Made? | Formation of Mars

By Tim Sharp published 12 December 17

Mars formed billions of years ago along with the rest of the solar system.

What is Mars Made Of? | Composition of Planet Mars

By Tim Sharp published 12 December 17

Mars is made of minerals, metals and other elements.

The Ultimate Test Flight: NASA's Shuttle Fleet at 25

Space Shuttle: The First Reusable Spacecraft

By Tim Sharp last updated 26 January 21

America's space shuttles were NASA's orbital workhorses.

Mysterious Moon Light Made by Glowing Dust Fountains

Atmosphere of the Moon

By Tim Sharp last updated 28 February 22

The moon's atmosphere is a very thin layer of widely dispersed gases.

Rosetta Spacecraft Deploying Philae Lander on Comet Artist Impression

Rosetta Spacecraft: To Catch a Comet

By Tim Sharp published 28 February 17

Rosetta was a spacecraft launched by the European Space Agency with a 10-year mission to rendezvous with a comet.

These close views of Pluto's four smaller moons were captured by NASA's New Horizons probe during its historic July 2015 flyby. Data from New Horizons suggests that at least two (and maybe even all four) were born from mergers of even smaller moons.

Pluto's Moons | Five Satellites of Pluto

By Tim Sharp published 23 February 16

Five moons orbit the dwarf planet Pluto: Charon, Nix, Hydra, Kerberos and Styx.

How Big is Mars? | Size of Planet Mars

By Tim Sharp published 2 August 12

Mars is the second smallest planet in the solar system. Here are Mars’ diameter, mass and other size measurements

V-22 Osprey: Controversial Dream Machine | The Most Amazing Flying Machines Ever

By Tim Sharp published 27 July 12

The V-22 Osprey takes off like a helicopter and flies like an airplane.

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