Francis Reddy


I'm a science writer on contract to NASA's Goddard Space Flight Center. I tweet whatever interests me, mostly space-related. I speak for no one but myself.

Photos and Videos by @francisreddy

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John Mather & Eric Smith discuss with reporters in the gallery of the clean room.

  • 196 days ago via site
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This 1/6th scale model of built by engineering students is fully deployable, like the real thing,

  • 196 days ago via site
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This is the big thermal-vacuum chamber , known as the Space Environment Simulator. shows off the facility during a press tour following #aas223.

  • 196 days ago via site
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Scientists "swiss cheesed" the radiator on #Hubble's WFPC 2 to sample locations struck by orbital debris.

  • 197 days ago via site
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#Hubble's workhorse Wide Field Planetary Camera 2 (1993-2009), seen during a press tour for #aas223.

  • 197 days ago via site
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No funny business now! The big "don't" in the entryway instructions for 's largest clean room.

  • 197 days ago via site
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David Spergel (, left) & 's Neil Gehrels (seated, right) tell students about the proposed WFIRST-AFTA mission at #aas223

  • 201 days ago via site
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At #aas223's Arecibo booth, folks make a planisphere with a difference -- it shows the radio sky!

  • 201 days ago via site
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Teddy Cheung () at #aas223 presser about gravitational lens work on Jan. 6

  • 201 days ago via site
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Atrium of the Gaylord National Resort & Convention Center in National Harbor, Md., site of #aas223.

  • 201 days ago via site
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"Reinflate! Reinflate!" A balloon #Dalek spotted at the convention center site of the #AAS223 meeting. #drwho

  • 203 days ago via site
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Comet ISON swoops around the sun and through Scorpius, detail of larger images here: This merges an SDO AIA 171 sun image (22:14 UT 11/28), SOHO C2 (20:36) and C3 (2030) images, and a DSS view of the sky in northern Scorpius. The comet broke apart and its fragments continue into space.

  • 241 days ago via site
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Screen grab of the first shot of the Moon from "2001: A Space Odyssey," brightened to better show detail, with some recognizable surface features labeled. These features are on the wrong side of the Moon from the shot's perspective, which is looking toward Earth. The lesson in this trivial example is that if you look hard enough at the products of pop culture, you can find science mistakes beyond artistic license in even the best-regarded examples. Whether that's important depends on your perspective, but nothing (and nobody's) perfect.

  • 294 days ago via site
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When we have the capability to image an exoEarth, what will we see? Here's what's described as a very optimistic simulated optical image of the solar system as seen from a distance of 10 parsecs (32.6 light-years). The challenge of imaging an Earth twin around a Sun twin from this distance is like imaging a firefly 1 meter from a searchlight located 2,000 km (1,240 miles) away. More in this presentation by Aki Roberge, NASA Goddard:

  • 333 days ago via site
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Mission patch flown on Apollo 13, donated to the Mitchell Gallery of Flight by astronaut James Lovell. The inscription reads: "This patch on board the Apollo 13 spacecraft April 11-17 1970 / To the Mitchell Gallery of Flight / James Lovell / Apollo 8, 13"

  • 371 days ago via site
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NASA flight helmet worn by astronaut James Lovell for flights in NASA aircraft (e.g.,the T-38 Talon) together with a photo of Lovell wearing the helmet prior to his Gemini 7 flight. Seen at the Mitchell Gallery of Flight, Mitchell International Airport, Milwaukee, Wisconsin.

  • 371 days ago via site
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Beautiful small-scale model (about 18" across) of the cockpit of a Caravelle 6R 80-passenger jet airliner, produced by the French firm Sud Aviation in the early 1960s. United Airlines was the only Caravelle operator in the U.S. and had 20 aircraft in its fleet. The model is on display at the Mitchell Gallery of Flight, Mitchell International Airport, Milwaukee, Wisconsin.

  • 371 days ago via site
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The SCORE system for classifying #solarstorms, or #CMEs, breaks them down by speed. The different SCORE types are S (speeds less than 500 km/s); C (for Common: 500 to 1,000 km/s); O (Occasional: 1,000 to 2,000 km/s); R (Rare: 2,000 to 3,000 km/s); and ER (Extremely Rare: speeds exceeding 3,000 km/s). For comparison, 1,000 km/s is 2.2 million mph or 3.6 million km/h. A video describing the classification scheme is available here:

  • 393 days ago via site
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As of May 2012, there were 994 operational satellites. Breakdown: 471 in low Earth orbit (LEO), like the International Space Station; 419 in geosynchronous orbits (GEO), an orbit used by most telecommunications satellites; 69 in medium Earth orbit (MEO), like GPS and the European navigation system, Galileo; and 35 in elliptical orbits. Here's where these orbits compare relative to Earth's radiation belts, which are filled with energetic charged particles. The area between the inner and outer belts is referred to as the slot region. This diagram is taken from "Space weather impacts on satellites and forecasting the Earth’s electron radiation belts with SPACECAST" (doi: 10.1002/swe.20023)

  • 515 days ago via site
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This chart shows the cumulative total of known near-Earth asteroids (NEAs) over time as of Jan. 2013. The blue area shows all near-Earth asteroids; red highlights only large NEAs with diameters more than roughly 1 km (about half a mile) across, which is thought to number about 1,000 objects. NASA's current search program is designed to discover 90% of the NEO population.

  • 525 days ago via site
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