From the Moon to Earth in HD

Lucas123 writes "The Japan Space Agency's Kaguya spacecraft is currently orbiting the moon and its equipment is being tested in preparation for its real mission to map the moon with high-definition images later this month. Almost as an afterthought, the space craft has recreated one of the most memorable photos in the history of spaceflight — an Earth-rise from lunar orbit."

Re:Not in HD

[hansamurai]

I was able to find two HD pictures:

http://www.selene.jaxa.jp/image/communication/img_071114_01.jpg [selene.jaxa.jp]
http://www.selene.jaxa.jp/image/communication/img_071114_02.jpg [selene.jaxa.jp]

1920x1080

Couldn't find anything else though. Disappointing.

Re:Not in HD

[LiquidCoooled]

For comparison, the original [nasa.gov].

http://dayton.hq.nasa.gov/IMAGES/LARGE/GPN-2001-000009.jpg [nasa.gov]

The older image appears to be higher resolution.

Re:Not in HD

[fbartho]

That older one looks like it was scanned in from a negative or a blown up film print. I don't know how you might accurately examine the real resolution comparitively.

Here's some real HD...

[Anonymous Coward]

... from 1968 (Apollo 8)!
http://history.nasa.gov/ap08fj/photos/b/as08-14-2383.jpg [nasa.gov]

... from 1976 (Viking)!
http://apod.nasa.gov/apod/image/mars_surface_vik2_big.jpg [nasa.gov]

... from 1979 (Voyager)!
http://oursun.open.ac.uk/images/jupiterp_cassini_full.jpg [open.ac.uk]

What makes this new "first HD camera in space" so special (yes, I know the Apollo images are shot on film, but Viking and Voyager had video cameras)?

Some movies

[wooferhound]

Look on this page for High Res Pics
http://www.jaxa.jp/press/2007/11/20071113_kaguya_e.html#pict01 [www.jaxa.jp]
and these movies of EarthRise and EarthSet
http://space.jaxa.jp/movie/20071113_kaguya_movie01_e.html [space.jaxa.jp]
http://space.jaxa.jp/movie/20071113_kaguya_movie02_e.html [space.jaxa.jp]

Re:Apollo

[Chosen Reject]

Not exactly what you were looking for, but relevant all the same. [cornell.edu] My compliments to hardburn [slashdot.org] for the link.

on TV in HD today

[MarcoAtWork]

it should be on in about half an hour (5pm PST) on Discovery HD for 30 minutes, not sure how much of the footage they're going to show (or if it's only on the Canadian Discovery HD) but it's on my cable box's IPG so do check it out, I seem to recall also that it will be repeated at least twice in the next few days.

Re:Earth doesn't move

[Technician]

Doesn't that infer the moon's rotation is 365.25 days?

No. If you thing of the earth and moon as orbiting each other, the earth could be considered in geostationary orbit. The earth and moon as they circle each other has the same side of the moon facing the earth at all times.

http://www.learner.org/channel/courses/essential/earthspace/session7/closer1.html [learner.org]
Orbital period (days) 27.32166
Rotational period (days) 27.32166
http://www.solarviews.com/eng/moon.htm [solarviews.com]

The moon has about 13 days a year.

Re:So what?

[MarcoAtWork]

120 film if properly scanned would qualify as way, way, way more than HD, especially if it was shot with decent glass (you can easily scan 120 film at 4800dpi, and it's 6 inches wide, you do the math...)

Public Relations

[iamlucky13]

The HD camera on SELENE is a PR instrument [selene.jaxa.jp]. Video is useful for things that change. The moon, for the most part, does not change, and the HD camera does not produce scientifically useful images of the moon. SELENE can only take about a minute worth of video.

High Definition as a proper noun generally refers to 1920x1080 resolution, but the various space agencies have produced much higher resolution images for years. The 35mm film shot during the Apollo missions is being scanned into 3070x2044 pixel images, for example, and the medium format film is being scanned at a huge 12800x12800 pixels. The Mars rovers carry 1 MP (1024 x 1024) cameras, and the images are often stitched together into far larger mosaics. I've seen some that even as JPG's take up over 100 MB (and crash IE). The Hubble Space Telescope's highest resolution camera is also only 1024x1024 pixels, and I believe this was chosen to approximate the maximum resolution of the optics, but again, large mosaics are common.

The High Resolution Imaging Scientific Experiment (HiRISE) camera aboard the Mars Reconnaisance Orbiter takes a different approach and is what's called a "push broom camera." Instead of taking rectangular pictures every so often, it scans a single line of up to 20,000 pixels continuously at the rate the spacecraft moves over the ground. In this way it builds up images up to 40,000 pixels long (800 megapixels...now that's high def!), at which point the file has to be transmitted to earth or the camera runs out of memory.

Re:Apollo

[Anonymous Coward]

There are some specs on the sensor here: http://www.jaxa.jp/press/2007/11/20071113_kaguya_e.html [www.jaxa.jp]

CCD(1920x1080)
Fixed lenses (T: tele camera, W: wide camera)
FoV T: 51.23(horizontal) 30.17(vertical)
        W: 15.60(horizontal) 8.80(vertical)

So if I'm doing this right then,
T: tan(51.23*pi/180)*100km/1920 = 64.8m/pixel (horizontal)
      tan(30.17*pi/180)*100km/1080 = 53.8m/pixel (vertical)
W: tan(15.60*pi/180)*100km/1920 = 14.5m/pixel (horizontal)
      tan( 8.80*pi/180)*100km/1080 = 14.3m/pixel (vertical)

Neither anywhere near 3m^2. :(

-brandon

Max resolution

[Ruben3d]

1920x1080 is the camera max resolution, you won't find anything better from this spacecraft. Info extracted from the bottom of this page: http://www.jaxa.jp/press/2007/11/20071113_kaguya_e.html [www.jaxa.jp]

Re:here we go again..

[trawg]

The industry standard rebuttal [badastronomy.com]

Re:The Earth never rises from the Moon

[bigmouth_strikes]

I assume that the concept of "the Earth rising from the Moon" is an artifact of the Satellite orbiting the Moon...

From the JAXA Selene site that is linked to from TFA:

we use the expression "Earth-rise" in this press release, but the Earth-rise is a phenomenon seen only from satellites that travel around the Moon, such as the KAGUYA and the Apollo space ship. The Earth-rise cannot be observed by a person who is on the Moon as they can always see the Earth at the same position.