Showing posts with label NASA. Show all posts
Showing posts with label NASA. Show all posts

Saturday, October 18, 2014

How to Photograph Comet Siding Spring by Mars, October 18-19

Comet C/2013 R1 Lovejoy and a Geminid Meteor, December 2013
Comet Siding Spring will pass Mars tomorrow, Sunday October 19, 2014.  The Orionid meteor shower is also underway, so you might get lucky and catch a meteor as well, like I did with this Geminid meteor I caught with Comet C/2013 R1 Lovejoy last December.

I see that my exposure was 8 seconds at ISO 5000 on a 50mm lens. It was an f/1.4 lens, so I was able to shoot at f/1.6. No star tracking mount was needed for up to a 10 second exposure with that lens.  With that long of an exposure, shouldn't the stars appear to be moving across the sky?  Using the "500 Rule", as long as the focal length times the exposure in seconds doesn't exceed 500, you should be fine.  So 50 x 8 = 400, and you get no visible star movement.

If you try a 400 mm lens however your maximum exposure goes to 1.25 seconds, so you'd need a star tracking mount.  Most people don't have star tracking mounts, so a good compromise might be an 85 mm lens offering f/1.8 or wider, keep the exposure around 5-6 seconds or less, and boost the ISO a bit is necessary.  The comet is approaching Mars now, so try it tonight, Saturday, for practice.

Seen from mid northern latitudes this weekend, Mars will be visible to the southwest from the end of evening twilight until it sets around 9/9:30 pm or so.  Good luck!

I performed lens tests with Comet C/2-013 R1 Lovejoy in 2013. I've put together a time-lapse video today to show you how they did. I've uploaded the video to YouTube here:


http://youtu.be/B-PCqS1KAT8

+NASA Goddard has produced a cool visualization showing how Comet Siding Spring will pass Mars, in this video:

Thursday, July 10, 2014

Delta II Rocket Image Sequence from OCO-2 Launch

Four minutes during NASA's OCO-2 satellite launch from Vandenberg AFB, California
NASA sent the OCO2 satellite up on a Delta II rocket last Wednesday morning, and I captured it on several different cameras at once.

+Philip Plait (The Bad Astronomer) goes into some detail on the satellite in his blog posNASA Launches a New Eye on Carbon Dioxide, so I'll stick to the photographic detail in the following sequence of photos matched to their corresponding events in the launch timeline.





2:55:53 a.m.
T-minus 30 seconds. SRB ignitors will be armed at T-minus 11 seconds.

The launch ignition sequence will begin at T-minus 2 seconds when a launch team member triggers the engine start switch. The process begins with ignition of the two vernier thrusters and first stage main engine start. The three ground-lit solid rocket motors then light at T-0 for liftoff.
2:56:23 a.m. 
LIFTOFF! Liftoff of the Delta 2 rocket with the Orbiting Carbon Observatory 2 to watch the Earth breathe from space!
T+plus 15 seconds. The launch vehicle is departing Vandenberg Air Force Base, heading south for the trek downrange over the Pacific carrying the OCO 2 spacecraft.


T+plus 36 seconds. Delta has broken the sound barrier, rapidly accelerating on the power of its first stage main engine and the three ground-lit strap-on solid-fuel boosters.
2:57 a.m. 
T+plus 50 seconds. The rocket has flown through the area of maximum aerodynamic pressure in the lower atmosphere.

2:57 a.m. 
T+plus 1 minute, 6 seconds. All three ground-start solid rocket boosters have burned out. The Delta 2's first stage RS-27A main engine is providing the sole thrust for the next couple of minutes.









2:58 a.m.
T+plus 1 minute, 50 seconds. The ATK-made solid rocket boosters have jettisoned from the first stage. They remained attached until the rocket cleared off-shore oil rigs.

T+plus 2 minutes. Delta now weighs half of what it did at liftoff two minutes ago.

2:59 a.m.
T+plus 2 minutes, 41 seconds. Delta now traveling at Mach 5.
T+plus 3 minutes. The first stage main engine still firing well. The Aerojet Rocketdyne powerplant consumes kerosene fuel and liquid oxygen to produce about 237,000 pounds of thrust.
3:00 a.m. 
T+plus 3 minutes, 34 seconds. The Delta 2 is now passing a speed of Mach 10.
3:01 a.m.
T+plus 4 minutes, 39 seconds. MECO. The first stage main engine cutoff is confirmed and the spent stage has been jettisoned.
T+plus 4 minutes, 44 seconds. The Delta's second stage has ignited! The engine is up and running.
T+plus 4 minutes, 51 seconds. The rocket's nose cone enclosing the satellite payload has been jettisoned.

3:02 a.m.
The rocket is at an altitude of 82.7 nautical miles, a downrange distance of 360 nautical miles and a velocity of 11,127 mph.



Here's NASA's diagram of the sequence (click on it  for a much larger view):



















Here's the whole sequence put together in a time-lapse video covering 3 hours prior to 1 hour after launch:


If night photography looks like something you'd like to master, I'm scheduling a night photography session at California's Bodie State Historic Park on July 25: http://www.jeffsullivanphotography.com/blog/bodie-night-photography-workshops/

Digital photography differs from film photography in many important respects, and nowhere is that more true than for night photography.  I've invested the sleepless nights learning the techniques and trade-offs to save you time and money required to discover it all for yourself.

Friday, July 04, 2014

NASA Launch This Week: Orbiting Carbon Observatory


NASA Orbiting Carbon Observatory Launch from Jeff Sullivan on Vimeo.

What happens when a time-lapse astrophotographer goes to a NASA launch?  Enjoy my latest edit of this new footage, just uploaded to +Vimeo :https://vimeo.com/99906771.  
NASA's OCO-2 Orbiting Carbon Observatory will take 1 million measurements daily at a resolution of one square mile, enabling the analysis of local, regional, national and global CO2 emissions and trends.
My new blog: www.JeffSullivanPhotography.com
#NASA #science #news #space #climatescience #NASAJPL #NASASocial #OCO2