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From a million miles away, NASA camera shows moon crossing face of Earth

nasa.gov

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Re: From a million miles away, NASA camera shows moon crossing face of Earth

#111

Post by markbnine »

thearn4 wrote: post #102
UserRights wrote: post #74

It is really cool how the NASA gives us a better understanding of the universe and our place in it by publishing all these nice pictures. However, I would like to have one easy accessible source for all the nice pictures that is daily updated and could be synchronized to a local school server e.g. with rsync. Is there one "ḧere-are-all-the-pics"-ftp server anywhere? It is quite time consuming to browse the hundreds o…

I'm a NASA engineer, and I think one of the problems that we recognize is just how much fragmentation there is between org units, projects, programs, and centers (each of which can be surprisingly autonomous). A single mission may have several "official" websites, depending on how the work is distributed across the agency. Your wish for a single-accessible source for images would be great. For that to happen, we woul…

I agree with the bunker mentality of the NASA centers. That said, the PDS (https://pds.nasa.gov/) is the closest thing to a central source for planetary data and imagery. And they run the photo journal (http://photojournal.jpl.nasa.gov/index.html)

Re: From a million miles away, NASA camera shows moon crossing face of Earth

#112

Post by Cthulhu_ »

mxfh wrote: post #103
kenbellows wrote: post #92

Honest question: Why don't the clouds seen on Earth show any activity or movement over the course of this time lapse?

There definitely is some movement: Look at the fine features of the northern arm of the vortex in the South, they change quite a bit. Also, there are some clouds growing just east of the Gulf of California. [EDIT] As it's arguably hard to spot with the low frame rate and movement I uploaded a stabilized and sped up version. It's centered on a cloud patch in the Pacific. You can now clearly see a cloud west of it disa…

If at all possible, please link to .gifv versions of imgur links; the .gif is a whopping 4.4 MB (compressed, 8.8 MB uncompressed), vs 737 KB as .webm in the gifv version.

TL;DR: do not use .gif as a video format.

Re: From a million miles away, NASA camera shows moon crossing face of Earth

#114

Post by markbnine »

exodust wrote: post #100

Here's what one million miles looks like side on...(whipped up in Photoshop) Best viewed at 100%. The image is more or less to scale. Scroll a million miles to the right to find moon and camera. (don't worry it's only a 300K jpeg) http://ozimg.s3.amazonaws.com/earth-moon-from-million-miles....

Nice. Also THEMIS took a shot in 2001 as it was headed to Mars that captured this distance.

http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA00559

Re: From a million miles away, NASA camera shows moon crossing face of Earth

#115

Post by cyanoacry »

gurtwo wrote: post #32

Why don't we see the Moon's shadow projected over the Earth in the pic? I guess it has to do with the relative distances of the 2 bodies to the Sun and the Moon's penumbra or something. Can someone make a digital image simulation of this to verify?

DSCOVR actually is in a "halo orbit" around L1, which means it's not sitting in the plane of the Earth-Sun orbit. From the DSCOVR site[1]: "The spacecraft will be orbiting [L1] in a six-month orbit with a spacecraft-Earth-sun angle varying between 4 and 15 degrees."

As some other folks have mentioned, the Moon's orbit is tilted a total of 5.2 degrees[2] relative to the Earth-Sun plane, so DSCOVR will see quite a number of DSCOVR-Moon-Earth alignments, but never a Sun-DSCOVR-Moon-Earth alignment.

[1] http://www.nesdis.noaa.gov/DSCOVR/

[2] http://hyperphysics.phy-astr.gsu.edu/hbase/solar/solecl.html

Re: From a million miles away, NASA camera shows moon crossing face of Earth

#116

Post by mxfh »

Cthulhu_ wrote: post #112
mxfh wrote: post #103

Earlier quoted context omitted.

There definitely is some movement: Look at the fine features of the northern arm of the vortex in the South, they change quite a bit. Also, there are some clouds growing just east of the Gulf of California. [EDIT] As it's arguably hard to spot with the low frame rate and movement I uploaded a stabilized and sped up version. It's centered on a cloud patch in the Pacific. You can now clearly see a cloud west of it disa…

If at all possible, please link to .gifv versions of imgur links; the .gif is a whopping 4.4 MB (compressed, 8.8 MB uncompressed), vs 737 KB as .webm in the gifv version. TL;DR: do not use .gif as a video format.

CC: NASA

Re: From a million miles away, NASA camera shows moon crossing face of Earth

#117

Post by sgustard »

kjs3 wrote: post #105
bdavisx wrote: post #75

Earlier quoted context omitted.

But also don't underestimate the stupidity, ignorance and/or anti-intellectualism of the general American (as well as other countries) population. Remember that 1/3 of Americans do not believe in evolution...

Why do you automatically think all or even most Twitter comments are from Americans?

Not all, just the dumb ones!

Also, two-thirds of native English speakers are in the US.

Re: From a million miles away, NASA camera shows moon crossing face of Earth

#118

Post by webXL »

TeMPOraL wrote: post #47
coldtea wrote: post #34

Earlier quoted context omitted.

The magic of reading!

Reading is the old-school local processing. Asking people is cloud computing, which is hot so it must obviously be better!

HN is becoming a free mechanical turk for reading.

Re: From a million miles away, NASA camera shows moon crossing face of Earth

#119

Post by vinhboy »

exodust wrote: post #100

Here's what one million miles looks like side on...(whipped up in Photoshop) Best viewed at 100%. The image is more or less to scale. Scroll a million miles to the right to find moon and camera. (don't worry it's only a 300K jpeg) http://ozimg.s3.amazonaws.com/earth-moon-from-million-miles....

Dang.. it never occurred to me how big the moon is.

Looking at this picture, it's hard for me to comprehend why the moon would orbit the earth and not fall into the sun.

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