Join Donate

Emily LakdawallaMay 1, 2015


There is one less robot exploring the solar system today. MESSENGER, which has orbited Mercury for four years, finally ran out of fuel and crashed into the planet at 17:26 UT on Thursday, April 30, 2015. The impact happened out of sight of Earth, with MESSENGER occulted by Mercury; we knew it was gone when it failed to reestablish contact with the Deep Space Network a few minutes later.

Well I guess it is time to say goodbye to all my friends, family, support team. I will be making my final impact very soon.

— MESSENGER (@MESSENGER2011) April 30, 2015

MESSENGER was just a robot, an inanimate object; but its human operators and fans were full of emotion yesterday as we stood vigil over its final moments. I watched, as I do, on Twitter. Some people responded to the emotional moment with jokes:

— Alex Parker (@Alex_Parker) April 30, 2015


— Alex Parker (@Alex_Parker) April 30, 2015

Others were sad.

You guys think "cries over space robots" is just a twitter bio gag but you're not watching me write this MESSENGER post

— Rachel Feltman (@RachelFeltman) April 30, 2015

Mary Kerrigan, noting that MESSENGER was crashing near the Mercury crater named for Shakespeare, looked for inspiration from the Bard.

@MazieK @HollowCrownFans @MESSENGER2011 The strong-wing’d Mercury should fetch thee up, And set thee by Jove’s side.

— William Shakespeare (@Wwm_Shakespeare) April 30, 2015

And fall upon the ground, as I do now, Taking the measure of an unmade grave - R&J A3s3 #MESSENGER #Shakespeare

— Mary Kerrigan (@MazieK) April 30, 2015

The yellows blues The purple violets & marigolds Shall as a carpet hang upon thy grave-P A4s1 #MESSENGER #Shakespeare

— Mary Kerrigan (@MazieK) April 30, 2015

Many, many people just watched, no doubt feeling lots of different things.

MESSENGER is at aphermion, speeding up towards Mercury for the last time. Sad day, but grateful for @MESSENGER2011

— Chris S (@anticitizen2) April 30, 2015

May the rest go peacefully my friend, @MESSENGER2011

— Steve Hauck (@hauck) April 30, 2015

Final LOS for Messenger prior to Mercury impact...

— Mike Seibert (@mikeseibert) April 30, 2015

MESSENGER was doing science to the very end....

Every second MESSENGER is talking to the Goldstone DSN station we are getting new science at Mercury. #totheend

— Steve Hauck (@hauck) April 30, 2015

...and even doing science that would never be returned to Earth.

@kotsuki_chan @elakdawalla @hauck As follow-on. At impact, the laser altimeter was firing, and at least one spectrometer was integrating.

— Noam Izenberg (@iyzie) May 1, 2015

And then it was over. The Deep Space Network antenna at Goldstone listened for MESSENGER to re-emerge from behind Mercury, and it didn't.

It's official. MESSENGER orbital operations have ended, the spacecraft signal was not reacquired. #thatsmessenger

— cratergirl (@cratergirl) April 30, 2015

To: @MESSENGER2011 So long & thanks for all the science From: Your friends in #DSN mission control

— NASA JPL (@NASAJPL) April 30, 2015

But it wasn't completely over. The Deep Space Network station at Canberra kept listening for MESSENGER, just in case. The tracking pass had been scheduled before the final date of MESSENGER's demise was known, and they kept the scheduled pass because of their usual thoroughness.

DSS45 listening for MESSENGER

Glen Nagle

DSS45 listening for MESSENGER
DSS-45 is a 34-meter antenna that was built in 1986 for the Voyager 2 flyby of Uranus. In this photo, taken on the morning of May 1, 2015 (local time), it is listening for a signal from MESSENGER, which had crashed into Mercury the day before.

At first, I found myself at a loss for what to say or think. I had a momentary feeling that the whole mission had never happened. If a spacecraft crashes on a distant planet and there's no human there to hear it, does it make a sound? I had imagined it there at Mercury for so long, and then it didn't exist anymore; I had the disconcerting feeling that I'd imagined it right out of existence. But Sarah Hörst brought me back to Earth with this crucial point:

The good news is that when we lose our space robots, we still get to keep our space robot people. — Sarah Hörst (@PlanetDr) April 30, 2015

Indeed, there are lots of space robot people who still have work to do with all the data that MESSENGER returned, down to the last moment.

In space, no one can hear you crash. Goodnight @Messenger2014

— David Rothery (@daverothery) April 30, 2015

Shortly after issuing the press release summarizing the spacecraft's death, the MESSENGER mission -- which will continue on Earth, at least, for at least a year or so, as they archive data -- gave us MESSENGER's final image.

MESSENGER's last image. 2 meters per pixel, in crater Jokai in Mercury's far north.

— Emily Lakdawalla (@elakdawalla) April 30, 2015

And of course there will be another Mercury mission that will allow us puny humans to take the science further, building on what MESSENGER sent us, and Mariner 10 before it.

Missing @MESSENGER2011 already? Follow @BepiColombo, the joint @esa / @JAXA_en mission headed for Mercury in 2017

— Tony Rice (@rtphokie) April 30, 2015

Farewell, MESSENGER. You did good.

My little @MESSENGER2011 spacecraft will be keeping me company the next couple weeks as we watch the mission end.

— Emily Lakdawalla (@elakdawalla) April 16, 2015
Mercury and the Pleiades, April 30, 2015

Stuart Atkinson

Mercury and the Pleiades, April 30, 2015
A look toward the innermost planet, on the day that its first orbiter crashed to ground.

Read more: Mercury, mission status, MESSENGER

You are here:
Emily Lakdawalla 2017 headshot square serene
Emily Lakdawalla

Solar System Specialist for The Planetary Society
Read more articles by Emily Lakdawalla

Comments & Sharing
Bill Nye and people
Let's Change the World

Become a member of The Planetary Society and together we will create the future of space exploration.

Join Today

The Planetary Fund

Help advance robotic and human space exploration, defend our planet, and search for life.


"We're changing the world. Are you in?"
- CEO Bill Nye

Sign Up for Email Updates